9th MCM – Dublin, Ireland, Jan 16 – 18

TD # Title Authors Abstract WGs
TD(19)09001 A Comparison of Knapsack Optimisation and CRE/ABS for MLB in Dense Self Organising Small Cells Karim M. Nasr and Klaus Moessner We investigate the performance of a new approach for mobility load balancing (MLB) and user association in future 5G dense small cell networks. This Self Organising Network (SON) approach uses a Knapsack Optimisation (KO) algorithm to evenly distribute users across a network of small cells. It is shown that the new technique achieves substantial improvements (better than four times reduction) in blocking ratios compared to the case when no MLB strategy is deployed. Comparisons with other MLB approaches relying on Cell Range Expansion (CRE) and Almost Blank Subframes (ABS) are presented highlighting the effectiveness of the new approach as a centralised self optimisation technique for future dense self organising small cells. DWG3: NET Layer,EWG-RA: Radio Access
TD(19)09002 Experimental Characterization of V2I Radio Channel in a Suburban Environment M. Yusuf, E. Tanghe, F. Challita, P. Laly, D. P. Gaillot, M. Lienard, L. Martens, and W. Joseph This paper describes the results of the experimental vehicle-to-infrastructure radio channel sounding campaign at 1.35 GHz performed in a suburban environment in Lille, France. Based on the channel measurements acquired in vertical and horizontal polarizations, a multitaper estimator is used to estimate the local scattering function for sequential regions in time, from which Doppler and delay power profiles are deduced. We analyze second order statistics such as delay and Doppler spreads, as well as small-scale fading amplitude. A similar behavior between both polarizations is observed. In both cases, the statistical distributions of the RMS delay and Doppler spreads are best fitted to a lognormal model. The small-scale fading of the strongest path is found to be Rician distributed, while the later delay taps show occasional worse-than-Rayleigh behavior. DWG1: Radio Channels,DWG2: PHY Layer
TD(19)09003 Cooperative Passive Coherent Location -A Promising 5G Service to Support Road Safety Reiner S. Thomä 5G promises many new vertical service areas beyond simple communication and data transfer. We propose CPCL (Cooperative Passive Coherent Location) being a distributed MIMO radar service which can be offered by mobile radio network operators as a service for public user groups. CPCL comes as an inherent part of the radio network and takes advantage of the most important key features proposed for 5G. It extends the well-known idea of passive radar (also known as Passive Coherent Location, PCL) by introducing cooperative principles. These range from cooperative, synchronous radio signaling, and MAC up to radar data fusion on sensor and scenario levels. By using both software-defined radio and network paradigms, as well as real-time mobile edge computing facilities intended for 5G, CPCL promises to become a ubiquitous radar service which may be adaptive, reconfigurable, and perhaps cognitive. Because CPCL makes double use of radio resources (both, in terms of frequency bands and hardware), it can be considered a green technology. Although we introduce the CPCL idea from the viewpoint of vehicle-to-vehicle/infrastructure (V2X) communication, it can definitely also be applied for many other applications in industry, transport, logistics, and for safety and security applications. Localisation and Tracking
TD(19)09004 Clutter loss measurements and simulations at 26 GHz and 40 GHz B. Montenegro-Villacieros, J. Bishop, J-M. Charea The World Radiocommunication Conference 2015, WRC-15, identified candidate frequency bands between 24.25 GHz and 86 GHz for future 5G systems. The Radio Spectrum Policy Group of the European Commission selected the 26 GHz band as pioneer for introducing next-generation 5G terrestrial wireless systems in the Union, and the 32 GHz and 40 GHz bands as promising and viable options in the longer term for 5G use. Sharing and compatibility studies for assuring the protection of services to which these bands are allocated on a primary basis are required before the WRC-19 allocates these frequencies to 5G services. These studies need propagation models to calculate interference levels at receivers. New propagation models are needed for the new frequencies and scenarios identified for 5G. New propagation models are developed through simulations or experimental measurement campaigns, each method having its pros and cons. The Joint Research Centre has started an activity working on both. This paper presents preliminary findings on use of a ray-tracing tool to produce clutter loss data and first comparisons with real experimental data, with the aim of validating the ray-tracing tool for the generation of new clutter loss data. DWG1: Radio Channels
TD(19)09005 Learning Approaches to Beam Selection for Hybrid Analog Beamforming Carles Antón-Haro, Xavier Mestre This paper investigates a number of deep-/machine-learning approaches to perform beam selection in mmWave communication systems. Specifically, we consider a hybrid beamforming setup comprising an analog beamforming (ABF) network followed by a zero-forcing baseband processing block. The goal is to select the optimal configuration for the ABF network based on the estimated AoAs and received powers of user equipments. To that aim, we consider (i) two supervised machine-learning approaches: k-nearest neighbors (kNN) and support vector classifiers (SVC); and (ii) a feed-forward deep neural network: the multilayer perceptron (MLP). Performance is assessed in terms of (i) classification accuracy, namely, the probability of selecting the (optimal) ABF resulting from an exhaustive search; and (ii) sum-rate. The impact of the actual AoA estimation scheme (minimum variance, MUSIC), as well as of a number of systems parameters (number of users, cardinality of the ABF codebook, beamwidth, or the size of training dataset) is also analyzed. DWG2: PHY Layer
TD(19)09006 Performance Modeling and Analysis for Vehicle-to-Anything Connectivity in Representative High-Interference Channels Thomas Blazek, Golsa Ghiaasi, Christian Backfrieder, Gerald Ostermayer , Christoph F. Mecklenbräuker All too often, the performance of vehicular communications is benchmarked merely for a single link. A major challenge for benchmarking the performance of multiple interacting vehicles is the definition of repeatable vehicular scenarios. In this paper, we propose and discuss an approach for performance analysis of the IEEE 802.11p standard in urban interference channels, by linking network simulations to a Software Defined Radio (SDR) setup. This approach provides communication performance measurements in the worst-case interference scenario caused by an urban traffic jam.We do this by starting out with vehicular traffic flow simulations and continue to model the medium access. We furthermore introduce an algorithm to reduce the complexity of the communication network while retaining its properties. Finally, we use a setup of SDRs encompassing the communication nodes and channel emulators that emulate urban channels to measure the packet level performance as a function of Signal-to-Interference Ratio (SIR) and distance to receiver under urban traffic conditions. EWG-IoT: Internet-of-Things
TD(19)09007 In-motion calibration of Wi-Fi-based indoor tracking systems for smartphones Miguel Martínez del Horno, Luis Orozco Barbosa and Ismael García-Varea With the growing development of smartphones equipped with Wi-Fi technology and the need for inexpensive indoor location systems, many researchers have focused on Wi-Fi-based indoor localization methods. However, due to the difficulties in characterizing the Wi-Fi radio signal propagation in such environments, the development of universal indoor localization mechanisms is still an open issue. In this work, we focus on the calibration of Wi-Fi-based indoor tracking systems to be used by smartphones. The primary goal is to build an accurate and robust Wi-Fi signal propagation representation in indoor scenarios. We propose a novel in-motion calibration methodology with three different signal propagation representations. We compare our new calibration proposal with a previously proposed motion-free (static) calibration methodology. Based on our experimental results, we show that the use of our motion-aware calibration mechanism significantly improves the localization accuracy. Localisation and Tracking
TD(19)09008 Accounting for Energy Cost When Designing Energy-Efficient Wireless Access Networks Greta Vallero, Margot Deruyck, Michela Meo, Wout Joseph Because of the increase of the data traffic demand, wireless access networks, through which users access telecommunication services, have expanded, in terms of size and of capability and, consequently, in terms of power consumption. Therefore, costs to buy the necessary power for the supply of base stations of those networks is becoming very high, impacting the communication cost. In this study, strategies to reduce the amount of money spent for the purchase of the energy consumed by the base stations are proposed for a network powered by solar panels, energy batteries and the power grid. First, the variability of the energy prices is exploited. It provides a cost reduction of up to 30%, when energy is bought in advance. If a part of the base stations is deactivated when the energy price is higher than a given threshold, a compromise between the energy cost and the user coverage drop is needed. In the simulated scenario, the necessary energy cost can be reduced by more than 40%, preserving the user coverage by greater than 94%. Second, the network is introduced to the energy market: it buys and sells energy from/to the traditional power grid. Finally, costs are reduced by the reduction of power consumption of the network, achieved by using microcell base stations. In the considered scenario, up to a 31% cost reduction is obtained, without the deterioration of the quality of service, but a huge Capex expenditure is required. DWG3: NET Layer
TD(19)09009 Electronically Steerable Parasitic Array Radiator Flush-Mounted for Automotive LTE Gerald Artner, Jerzy Kowalewski, Jude Atuegwu, Christoph F. Mecklenbräuker, Thomas Zwick A pattern reconfigurable antenna for 2.6GHz LTE is flush-mounted in a chassis antenna cavity. The driven element is a top-loaded monopole, that is steered based on the electronically steerable parasitic array radiator (ESPAR) principle. The radiation pattern can be configured in 45 degree steps, e.g. front, diagonal front-right, right, etc. The cavity prototype is made from carbon fiber reinforced polymer and includes a chassis mockup. Antenna performance is evaluated based on measured gain patterns, which show that the antenna retains its reconfiguration capabilities when it is flush-mounted. Further, a parametric measurement study with regards to antenna height inside the cavity is performed to investigate the option of mounting an electronics module underneath the antenna. EWG-IoT: Internet-of-Things
TD(19)09010 Aerial Coverage Analysis of Cellular Systems at LTE and mmWave Frequencies Using 3D City Models Achiel Colpaert, Evgenii Vinogradov, Sofie Pollin Cellular connectivity for UAV systems is interesting because it promises coverage in beyond visual line of sight scenarios. Inter-cell interference has been shown to be the main limiting factor at high altitudes. Using a realistic 3D simulator model, with real base station locations, this study confirms that UAVs at high altitudes suffer from significant interference, resulting in a worse coverage compared to ground users. When replacing the existing base stations by mmWave cells, our results indicate that ground coverage is decreased to only 90%, while UAVs just above rooftop level have a coverage probability of 100%. However, UAVs at higher altitude still suffer from excessive interference. Beamforming has the potential to improve mmWave link budget and to decrease interference and is for this reason a promising technology for ensuring connectivity to aerial users. DWG2: PHY Layer,EWG-RA: Radio Access
TD(19)09011 300 GHz Channel Measurements in a Real Data Centre Johannes M. Eckhardt, Tobias Doeker, Sebastian Rey, Thomas Kürner In this temporary document a measurement campaign in a real Data Centre at 300 GHz and recent results are presented. The measurements are performed with a UWB sub-mmWave channel sounder and classified in general characterisation, top-of-rack and intra-rack measurements. The individual measurement setups as well as the methodology are explained. In a first step, the measurements are evaluated regarding the path attenuation, the power delay profile (PDP) and the power angular spectrum (PAS). The PDP as well as the PAS give comprehensible results, which are explained by the scenario’s geometry. The path attenuation shows reasonable results compared to the free space path loss and demonstrates that wireless communication at 300 GHz in a Data Centre is possible. DWG1: Radio Channels
TD(19)09012 Joint Received Signal Strength, Angle-of-Arrival, and Time-of-Flight Positioning David Plets, Wouter Deprez, Jens Trogh, Luc Martens, Wout Joseph This paper presents a software positioning framework that is able to jointly use measured values of three parameters: the received signal strength, the angle-of-arrival, and the time-of-flight of the wireless signals. Based on experimentally determined measurement accuracies of these three parameters, results of a realistic simulation scenario are presented. It is shown that for the given configuration, angle-of-arrival and received signal strength measurements benefit from a hybrid system that combines both. Thanks to their higher accuracy, time-of-flight systems perform significantly better, and obtain less added value from a combination with the other two parameters. Localisation and Tracking
TD(19)09013 Wideband Off-Body Channel Characteristics with Dynamic User Kenan Turbic, Slawomir J. Ambroziak, Luis M. Correia, Marko Beko This paper presents the preliminary results of a dynamic off-body channel characterisation study, based on wideband measurements at 5.8 GHz in an indoor environment. The Channel Impulse Response (CIR) was measured for a scenario with the user approaching and departing from the off-body antenna. A CIR deconvolution procedure was performed jointly in two polarisations, and the received signal power, Cross-Polarisation Discrimination (XPD), delay mean and standard deviation were calculated based on the estimated path delays and amplitudes. The statistical analysis is performed, and the obtained results show large variations of the CIR parameters. The XPD is observed to vary up to 21.3 dB. SEWG-IoT: Internet-of-Things for Health
TD(19)09014 Polarization Planning for Wireless Networks Philippe Ezran, Yoram Haddad, Merouane Debbah Polarization diversity enables frequency reuse in a telecommunication network. The most widely considered solution is to use two orthogonal polarization on the same link, which enables to double the available bandwidth. In this paper, we study the possibility to connect the nodes of a ring topology network with one single channel for all the links, with the condition that the polarization of any link is orthogonal to the polarization of the two adjacent links. The solution proposed in this paper can improve spectrum efficiency by up to 50% in comparison with the widespread polarization multiplexing solution. Furthermore, it has implications on network topology and channel allocation. DWG3: NET Layer
TD(19)09015 Impact of Spatial Consistency on Dynamic Beamforming for Millimeter-Wave Cellular Systems Harsh Tataria and Fredrik Tufvesson Millimeter-wave (mmWave) frequencies are set to play an important role in fifth-generation (5G) wireless systems. A pre-requisite for the design and performance assessment of 5G wireless is the understanding of the involved propagation processes and derivation of practical channel models. Unlike contemporaneous bands below 6 GHz, several advanced modelling features need to be catered for at mmWaves due to the highly directional nature of the channel, and the presence of larger bandwidths. For dynamic scenarios, spatial consistency (SC) is a novel mandatory feature of 5G channel models, ensuring continuity in the channel parameters as the user equipment (UE) moves along a trajectory. Such mobility has an enormous impact on the performance of common beamforming techniques to deliver high spectral efficiencies. Different to previous studies, this work aims to quantify the impact of SC on dynamic mmWave beamforming performance. Our focus is on the downlink of a 28 GHz urban microcellular scenario, where the base station comprises of a 16×16 cross-polarized uniform planar array (UPA) serving multiple 4×4 UPA UEs. Using the recently standardized SC procedures from the Third Generation Partnership Project/International Telecommunication Union TR 38.901/M.2412-0 SC, we evaluate the ergodic spectral efficiencies with maximum-ratio transmission and zero-forcing beamforming. Remarkably, our results show that at practical signal-to-noise-ratio levels, spatially consistent channel responses result in approximately 40% loss of ergodic spectral efficiency relative to the case without SC due to substantial correlation amongst the large-scale parameters. We demonstrate the validity of this conclusion with varying UE trajectories. The presented results serve as a cautionary tale to recalibrate our performance expectations of realistic dynamic mmWave beamforming. DWG1: Radio Channels
TD(19)09016 Characterization of slow and fast fading in off-body communication at 2.45 GHz with space diversity scheme in indoor environment Szymon Wiszniewski, Slawomir J. Ambroziak The characterization of slow and fast fading in WBAN networks with space diversity scheme has been presented. The analysis, based on the measurements at 2.45 GHz in indoor environment, has also shown that for all investigated configurations of receiving antennas the correlation coefficient values of received signals’ parameters are below the assumed value of 0.5, being close to zero for the vast majority of cases. It has been shown that the slow fading component may be modelled by a lognormal distribution with zero average and the standard deviation from the range of [1.43, 1.98] dB. The fast fading component is the best modelled by a Rice distribution with the non-centrality parameter and the scale parameter being in the range [0.8125, 0.9624], and [0.5269, 0.6954], respectively. SEWG-IoT: Internet-of-Things for Health
TD(19)09017 A Novel Bitrate Adaptation Method for Heterogeneous Wireless Body Area Networks Krzysztof K. Cwalina, Sławomir J. Ambroziak, Piotr Rajchowski, Jarosław Sadowski, Jacek Stefański In the article, a novel bitrate adaptation method for data streams allocation in heterogeneous Wireless Body Area Networks (WBANs) is presented. The efficiency of the proposed algorithm was compared with other known algorithms of data stream allocation using computer simulation. A dedicated simulator has been developed using results of measurements in the real environment. The usage of the proposed adaptive data streams allocation method by transmission rate adaptation based on radio channel parameters can increase the efficiency of resources’ usage in a heterogeneous WBANs, in relation to fixed bitrates transmissions and the use of well-known algorithms. This increase of efficiency has been shown regardless of the mobile node placement on the human body. SEWG IoT for Health
TD(19)09018 Person tracking in a Ferry Environment Using Ultra Wideband Radio Interface Piotr Rajchowski, Krzysztof Cwalina, Jaroslaw Sadowski This article presents research and analysis of effectiveness of moving people tracking in a passenger ferry environment using measurements of propagation time of an ultra-wide band radio signal. Constructed measurement stand and results of measurements carried out in real propagation conditions were shortly discussed. EWG-IoT: Internet-of-Things,Localisation and Tracking
TD(19)09019 Detection of Row-Sparse Matrices with Row-Structure Constraints David Gregoratti, Carlos Buelga, and Xavier Mestre An underdetermined multi-measurement vector linear regression problem is considered where the parameter matrix is row-sparse and where an additional constraint fixes the number of nonzero elements in the active rows. Even if this additional constraint offers side structure information that could be exploited to improve the estimation accuracy, it is highly nonconvex and must be dealt with with caution. A detection algorithm is proposed that capitalizes on compressed sensing results and on the generalized distributive law (message passing on factor graphs). DWG2: PHY Layer
TD(19)09020 Experimental Characterization of the in-to-out-Body Path Loss at 433 MHz for Dairy Cows Said Benaissa, David Plets, Denys Nikolayev, Leen Verloock, Günter Vermeeren, Margot Deruyck, Luc Martens, Frank André Maurice Tuyttens, Bart Sonck, and Wout Joseph In this paper, the in-to-out-body path loss between an antenna placed inside cows’ rumen and a distant gateway was determined at 433 MHz. Measurements were conducted on seven fistulated cows using signal generator and spectrum analyser equipment. The measurements were conducted also without cows to quantify the path loss increase due to the cow body. Based on the obtained results, the path loss increased in average by 45.5 dB (all cows). The increase varied between 39.7 dB (cow 4) and 51.1 dB (cow 7). In addition the measured path loss values were used to model the path loss as a function of the transmitter-receiver distance. The path loss was well fitted by a log-normal model with a path loss exponent of 1.9 and path loss at reference distance of 98 dB. Finally, the obtained models were used to calculate the range of a LoRa based network. The ranges varied between 1 and 100 meters depending on the used transmit power and bit rate. DWG2: PHY Layer,EWG-IoT: Internet-of-Things,SEWG-IoT: Internet-of-Things for Health
TD(19)09021 5G Multi-band Double-directional Street Canyon Measurements in Germany Diego Dupleich, Robert Müller, Sergii Skoblikov, Jian Luo, Giovanni Del Galdo, and Reiner S. Thomä In the present paper we introduce the results of simultaneous multi-band ultra-wideband measurements at 6.75, 30, and 60 GHz in a street canyon scenario under LOS in Germany. This is the first part of a street canyon measurements series using the same channel sounder in different parts of the world. The aim of these measurements is to analyse and compare the propagation characteristics with multi-band channel modelling in view. We show that from the propagation perspective, mm-waves offer very similar opportunities than the well known and exploited sub-6 GHz bands. DWG1: Radio Channels
TD(19)09022 Dynamic Polarimetric Wideband Channel Sounding in an Elevator Shaft Pasi Koivumaki, Mikko Heino, Katsuyuki Haneda, Mikko Puranen and Johanna Pesola We report results from dynamic polarimetric wideband channel sounding in an elevator shaft for the first time in the literature. Transmitter and receiver are fixed to a roof of an elevator car and top of the elevator shaft, respectively, to test radio link connectivity for infotainment display inside the car. To this end, we develop a real-time wideband channel sounder based on software-defined radios, capable of 160 MHz instantaneous bandwidth with varying carrier frequency from a few hundred MHz to 6 GHz. The sounder does not provide sufficient phase synchronization over time, but delay synchronization was found stable for estimation of absolute delay and Doppler spectrum. The results show significantly higher pathloss at 2.45 GHz for electric fields parallel to the longer side of the shaft than to the shorter side due to a break point. The power delay and Doppler spectrum showed significant amount of scattering for short transmitter-receiver separation due to surrounding clutters. The multipath richness decreased as the separation is longer. For the fixed power threshold in estimating a delay spread, 2.45 GHz channels had a higher estimates than 5.8 GHz when the car is at the top of shaft, while it was lower for the rest of car locations in the shaft. DWG1: Radio Channels,EWG-IoT: Internet-of-Things
TD(19)09023 A QoE-driven traffic steering algorithm for LTE networks María Luisa Marí-Altozano, Salvador Luna-Ramírez, Matías Toril Due to the huge increase in traffic and services in mobile networks, network management has changed its main focus from Quality of Service (QoS) to a Quality of Experience (QoE) perspective. In addition, SON (Self Organizing Networks) techniques have been developed to automate network management, being load balancing a key use case. Load balancing aim is to balance the traffic among adjacent cells. This balance is expected to decrease the overall blocking ratio, thus increasing the total carried traffic in the network. Nevertheless, these techniques may fail when QoE perspective is considered. In this work, a novel QoE balancing algorithm is proposed to reach QoE equilibrium in a realistic LTE network with different services. The proposed balancing approach is tested and compared with classical techniques by means of simulations. EWG-RA: Radio Access
TD(19)09024 Massive MIMO for Industrial Scenarios : Measurement-Based Poalrimetric Analysis. Frédéric Challita, Pierre Laly, Martine Liénard, Emmeric Tangue, Wout Joseph, Davy P. Gaillot The massive polarimetric channel is evaluated for three different frequencies (1.3, 3.5 and 6 GHz) in an industrial scenario. The analysis is based on (1) propagation characteristics using classical parameters such as average received power and spatial channel correlation and (2) system-oriented metrics such as sum-rate capacity with linear precoding techniques and water-filling. The results show that in indoor industrial scenarios, polarization diversity can greatly benefit different aspects of the system design. Results for sum-rate capacity are promising and show that the extra degree of freedom provided by polarization diversity can optimize the performance of linear precoders, notable, the maximum-ratio transmitter. DWG1: Radio Channels
TD(19)09025 Hybrid Ray-Tracing/FDTD method for propagation modelling of a massive MIMO technology in an industrial indoor environment Sergei Shikhantsov, Arno Thielens, Gunter Vermeeren, Emmeric Tanghe, Piet Demeester, Luc Martens, Guy Torfs, Wout Joseph This paper presents a numerical approach for massive MIMO propagation modelling. It combines Ray-Tracing for estimation of the wireless channel on a large scale and the Finite-Difference Time-Domain method to simulate propagation of the electromagnetic field (EMF) in proximity of the user equipment. We apply it to estimate the EMF propagation in a model of an industrial indoor environment with a single massive MIMO base station. Studied scenarios include line-of-sight and non-line-of-sight propagation with the base station using Equal Gain Transmission, Maximum Ratio Combining and Zero Forcing precoding schemes at 3.5~GHz. Calculated channel parameters are discussed in comparison with the data available in literature. DWG1: Radio Channels,DWG2: PHY Layer
TD(19)09026 A data-driven user steering algorithm for optimizing user experience in multi-tier LTE networks C. Gijón, M. Toril, S. Luna-Ramírez, M. L. Marí-Altozano Multi-tier cellular networks are a cost-effective solution for capacity enhancement in urban scenarios. In these networks, effective handover schemes are required to assign users to the most adequate layer. In this paper, a data-driven self-tuning algorithm for user steering is proposed to improve the overall Quality of Experience (QoE) in multi-carrier Long Term Evolution (TE) networks. Unlike classical approaches, user steering is achieved by changing Reference Signal Received Quality (RSRQ) based inter-frequency handover margins. To drive the tuning process, a novel indicator showing throughput changes in the vicinity of handovers is derived from connection traces. Method assessment is carried out in a dynamic system-level LTE simulator implementing a real multi-carrier scenario. Results show that the proposed algorithm significantly improves QoE figures obtained with a classical inter-frequency handover scheme based on Reference Signal Received Power (RSRP) measurements. EWG-RA: Radio Access
TD(19)09027 Formulation of Possible Extensions to the ITU-R P833-8 Recommendation on Attenuation in Vegetation at Frequencies Above 1 GHz Nuno Leonor; Rafael Caldeirinha; Telmo Fernandes This document aims to give an overview on current research approaches and propagation models for attenuation in vegetation, developed within the research group on “Antennas and Propagation –Lr” of the Instituto de Telecomunicações, in Portugal, and University of South Wales, in the UK, along with some results and comparisons with experimental data gathered at varies frequencies. This is a result of the work that has been done in Europe, particularly at the standardization bodies, in which contributions have been made to predictions models and measured data to the International Telecommunication Union – Radiocommunication Sector (ITU-R) recommendations on Propagation (P), i.e. ITU-R P.833-5. Topics will address formulation of possible extensions of the ITU-R P.833-8 based on recent results on analytical and experimental studies directed at the characterization and modeling of vegetation media effects on propagation and radio system design, including dynamic effects. DWG1: Radio Channels
TD(19)09028 Mobility Model-Based Non-Stationary Mobile-to-Mobile Channel Modeling Ruisi He , Bo Ai, Gordon L. Stüber, Zhangdui Zhong Non-stationary mobile-to-mobile (M2M) channel modeling has gained strong momentum as it is vital for developing M2M communications technology. Traditional geometry-based channel models (GSCMs) for M2M communications usually assume fixed velocity and moving direction, which differs from the realistic M2M scenarios and also makes it difficult to incorporate non-stationarity of channel into the regular-shaped GSCMs. In this paper, a mobility model-based method is proposed to incorporate non-stationarity into M2M channel modeling by introducing dynamic velocities and trajectories. A revised Gauss–Markov mobility model is first presented together with the cluster-based two-ring M2M reference model. The mobility model uses tuning parameters to adjust the degree of mobility randomness and covers different M2M mobility trajectories. Then, a closed-form time-variant time-frequency correlation function and the Doppler power spectrum are derived from the model. Based on the numerical analysis, it is found that for a regular-shaped GSCM with a fixed M2M scattering environment, the motion does not introduce non-stationarity, however, the dynamic motion (i.e., the changes of velocity and moving direction) leads to non-stationarity, which is reflected by the time-variant time correlation function and Doppler spectrum. Different propagation modes, cluster number, and intra-cluster nonisotropic scattering also have major impacts on channel nonstationarity. Moreover, the randomness of the mobility model is found to significantly increase the degree of channel nonstationarity. These conclusions are useful for M2M non-stationary channel simulation and communication system evaluation. DWG1: Radio Channels
TD(19)09029 A Kernel-Power-Density-Based Algorithm for Channel Multipath Components Clustering Ruisi He, Qingyong Li, Bo Ai, Yang Li-Ao Geng, Andreas F. Molisch, Vinod Kristem, Zhangdui Zhong, Jian Yu Cluster-based channel modeling has been an important trend in the development of channel model, as it maintains accuracy while reducing complexity. Whereas a large number of channel measurements have shown that multipath components (MPCs) are distributed as groups, i.e., clusters, existing clustering algorithms have various drawbacks with respect to complexity, threshold choices, and/or assumptions about prior knowledge. In this paper, a kernel-power-density (KPD)-based algorithm is proposed for MPC clustering. It uses the kernel density of MPCs to incorporate the modeled behavior of MPCs and takes into account the power of the MPCs. Furthermore, the KPD algorithm only considers the K nearest MPCs in the density estimation to better identify the local density variations of MPCs. A heuristic approach of cluster merging is used to improve the performance. Both simulation and channel measurements validate the KPD algorithm, and almost no performance degradation is found even with a large number of clusters and large cluster angular spread, which outperforming other algorithms. The KPD algorithm enables applications in multipleinput–multiple-output channels with no prior knowledge about the clusters, such as number and initial locations. It also has a fairly low computational complexity and can be used for clusterbased channel modeling. DWG1: Radio Channels,Localisation and Tracking
TD(19)09030 Millimeter-Wave Scattering Process Identification and Cluster Characterization Minseok Kim, Satoru Kishimoto, Tatsuki Iwata, Shigenobu Sasaki, Jun-ichi Takada In radio channel measurement and modeling to develop and evaluate advanced wireless systems at high frequency, directional scanning by highly directive antennas is the most popular method to obtain angular channel characteristics. However, it is often insufficient for ray-/cluster-level characterization and channel modeling since the angular resolution of the measured data is actually limited by the angular sampling interval and antenna half-power beamwidth for a given scanning angle range. In this paper, the subgrid CLEAN algorithm is proposed, which is a novel technique for high-resolution multipath component (MPC) extraction from the multi-dimensional power image, so-called double-directional angular delay power spectrum. This technique can successfully extract the MPCs by using the multi-dimensional power image even in the presence of the carrier phase drift. In this paper, by applying the developed technique to the measured data taken at 58.5 GHz in indoor environments assuming the indoor hotspot access scenario in the fifth generation mobile system, the scattering processes are identified and the multipath clusters are characterized. DWG1: Radio Channels
TD(19)09031 EMPOWER – Empowering Transatlantic PlatfOrms for advanced WirEless Research Per Hjalmar Lehne EMPOWER has the ambition to accelerate the joint development between the EU and the US of advanced wireless platforms targeting the new connectivity frontiers beyond 5G. EMPOWER targets the creation of a joint EU-US advanced wireless ecosystem for (i) bridging the relevant EU-US Wireless communities and stakeholders, such as scientific researchers, platform engineers, standardization experts, regulators, and product incubators; and (ii) developing a strategic EU-US collaboration agenda and supporting its execution ahead of worldwide competition for beyond 5G connectivity standards based on common EU-US roadmaps spanning advances in scientific knowledge, platforms and testbeds, standards and regulations. DWG1: Radio Channels,DWG2: PHY Layer,DWG3: NET Layer,EWG-RA: Radio Access
TD(19)09032 Combining Measurements and Simulations for Evaluation of Tracking Algorithms Klemen Bregar, Roman Novak, Tomaž Javornik, Mihael Mohorčič Wireless device position tracking has been already thoroughly studied in literature. Most of the studies rely on the presumption that location information is acquired based on range measurements that are performed in a very short period of time. However, in time-division-multiple-access (TDMA) two-way-ranging (TWR) ultra-wideband (UWB) wireless localization networks, those ranging measurements are always spread in time by significant time delays. Those delays have negative impact on the tracking performance and the effects of ranging in these systems should be evaluated accordingly. In this paper we propose a time-of-flight (ToF) simulation-based approach for indoor tracking algorithm evaluation with a measurement calibration which enables changing the size of TDMA slots and thus observing the tracking performance degradation. A constant velocity movement model with a random curvature of walking path is proposed to simulate the person’s random walking pattern inside the room as naturally as possible. With a proposed simulation framework the impact of individual hyperparameter changes on tracking performance can be evaluated. Localisation and Tracking
TD(19)09033 Frequency Trends of Radio Wave Propagation in the range 1-100 GHz Jonas Medbo Next generation of mobile communications, 5G, is planned for utilizing a very wide range of radio spectrum from below 1 GHz up to about 100 GHz. Most of this spectrum will be allocated at radically higher frequencies than the spectrum used in current mobile networks. The higher frequencies are needed for providing sufficient amount of spectrum for the required bitrates and network capacities of 5G. In order to optimize 5G radio networks it is crucial to know well the radio propagation characteristics, and corresponding frequency dependence, over the full 5G frequency range. This presentation summarizes the current understanding of radio wave propagation frequency trends in terms of 3GPP, ITU-R and mmMAGIC models. Both propagation loss, and, delay and angle spread characteristics are covered. The propagation loss results are essentially coherent between the different models, showing some weak to strong frequency trends depending on propagation scenario. Regarding angle and delay spread the substantial frequency dependence of the 3GPP model is challenged based on the mmMAGIC results which show that there is no clear frequency dependence. DWG1: Radio Channels
TD(19)09034 On the Coexistence of LTE and LoRa in the 2.4 GHz ISM Band Ladislav Polak, Martin Potocnak, Jiri Milos, Tomas Kratochvil This paper deals with the study of possible coexistence scenarios between the Long Term Evolution (LTE) and the low power wide area networks (LPWANs) in the 2.4 GHz band. In the future, these technologies can utilize the unlicensed industrial, scientific and medical (ISM) bands. In this work, we focus on the performance analysis of LTE affected by interfering LoRa RF signal on the physical layer (PHY) level. For this purpose, an appropriate measurement setup with reliable evaluation process is proposed. Functionality of the adopted concept and the proposed measurement setup are verified by laboratory measurements. The obtained results are evaluated as a dependence of protection ratio (PR) on the length of the guard band (GB). DWG2: PHY Layer
TD(19)09035 Concept and structure of the localization module in project “Innovative method of localization airplanes in VCS (VCS-MLAT) distributed system” Szymon Wiszniewski The article presents the concept and the structure of the localization module. The prototype module is the part of the VCS (VCS-MLAT) localization distributed system. The device receives the audio signal transmitted in airplanes band (118 MHz – 136 MHz). Received data with the timestamps are send to the main server. The data from multiple devices estimates the localization of the airplane. The main aim of the project is the analysis of the innovative airplane localization method in the close to real environment, based on the audio signal transmitted in 118 MHz – 136 MHz band. The development work requires elaboration and implementation of the prototypes of the distributed system. This concept will increase security in civil and military aviation in the situation when the rests localization systems failed. The localization module as a part of the VCS localization system contains: motherboard with System on Chip integrated circuit, analog radiostation, GPS receiver and ADS-B receiver. The audio signal received from radiostation is sampled and send with the timestamps synchronized by the GPS module to the main server. Moreover, the verification of proper working VCS-MLAT system will be provided by ADS-B receiver. The special software in the main VCS system server is responsible for the estimation of aircraft position with the cooperation of dedicated localization modules, which are placed on monitored area. The concept of radiolocalization system based on the VCS communication structure should be considered as unique, compared to actual systems. Localisation and Tracking
TD(19)09036 Fading Analysis in Off-Body Channels in a Straight Metallic Corridor in a Passenger Ferry Environment Pawel T. Kosz, Slawomir J. Ambroziak, Luis M. Correia, Jacek Stefanski This paper presents a fading analysis for Body Area Networks off-body communications at 2.45 GHz in a passenger ferry environment. The results are based on measurements performed for dynamic scenarios in a straight metallic corridor. Two components, extracted from instantaneous system loss values, have been analysed: small- and large-scales fading, separately for each scenario. Well-known probability distribution functions have been fitted to the empirical distributions by using Goodness of Fit tests. The slow fading component is best modelled by the Lognormal Distribution, with 0 dB mean and [1.22, 2.88] dB standard deviation parameters, while the fast fading one is by the Nakagami-m Distribution with [0.78, 0.91] shape and [1.9, 2.18] scale parameters. SEWG-IoT: Internet-of-Things for Health
TD(19)09038 Impact of beamforming on human shadowing in rich scattering environment: a numerical analysis Thomas Pairon, Claude Oestges, Christophe Craeye This work investigates the shadowing caused by humans on a communication link at 60GHz in an environment containing many reflectors (e.g. industrial factories). At high frequencies, a human body crossing the LOS can attenuate the received power by up to 30 dB. The goal of this paper is to evaluate the effective human blockage effect when the system takes advantage of the environment through beamforming. Preliminary results show that in a NLOS scenario, precoding of the transmitted signal increases significantly the received power when compared to a transmitted signal without precoding. The analysis is carried out for two-dimensional scenarios through an accelerated full-wave approach, where the human walk is efficiently taken into account. A comparison between an optimal precoder and a codebook-based beamformer is eventually performed. DWG1: Radio Channels
TD(19)09039 EMF evaluations for future networks based on Massive MIMO Claudia Carciofi, Samuela Persia, Stefano D’Elia, Riccardo Suman Future networks will permit to reach high level of connectivity and capacity in order to respond to the growing traffic needs of the next years. It means that, future fifth generation of mobile network (5G) and existing fourth (4G) Long Term Evolution (LTE) network, will be characterized by a very large installations deployment in terms of macro/micro/femto cells. In addition the introduction of active antenna technologies will permit to enhance performance in terms of capacity. This new paradigm suggests to revise RF EMF (Radio Frequency Electromagnetic Field) compliance assessments for the regulatory requirements on human exposure by using new metrics measurements no more based on deterministic maximum transmitted power evaluations. In this work we consider: a statistical model to define real emission by using massive MIMO; and a new combined model of statistical MIMO power model with a statistical EMF evaluation, as used in Italy, in order to identify new metrics for EMF emission analysis of future networks. DWG1: Radio Channels,EWG-RA: Radio Access
TD(19)09040 Electromagnetic field levels massive monitoring in 5G scenarios: dynamic and standard measurements comparison Claudia Carciofi, Andrea Garzia, Simona Valbonesi, Alessandro Gandolfo, Roberto Franchelli The document presents a potentially innovative methodology for carrying out large-scale measurements of radiofrequency electromagnetic field and low frequency electric and magnetic field. The system consists in performing measurements using a control unit equipped with the appropriate probes positioned on the roof of a car moving along the territory (dynamic measurements). Aim of the work is the validation of the measurements carried out in a dynamic way by comparing the results of surveys carried out at strategic points, selected for their electromagnetic characteristics, in dynamic mode or following the CEI 211-7 guidelines (for the radiofrequency fields) and 211-6 (for low frequency fields). The possibility to perform massive measurements in a short time could become extremely useful in the future, when the implementation of the new 5G services will lead to an increased use of the electromagnetic spectrum, with consequent increase of electromagnetic field levels. DWG2: PHY Layer
TD(19)09041 Radio Frequency Electromagnetic Field Exposure Assessment for future 5G networks Claudia Carciofi, Samuela Persia, Marina Barbiroli, Daniele Bontempelli, Giuseppe Anania The fifth generation of mobile network (5G) will be based not only on the expansion of existing fourth (4G) Long Term Evolution (LTE) network, but thanks to the introduction of new radio access in the millimetre wave bands will permit to improve requirements in terms of connectivity and capacity. Specifically, 5G network will be characterized by increasing in available spectrum at higher frequencies with a very large number of antenna elements deployment. As a consequence, the RF EMF (Radio Frequency Electromagnetic Field) compliance assessments for the regulatory requirements on human exposure analysis for the installation permission needs to be revised accordingly. In this work, a Country case (Italy), where the restrictive regulation is applied, has been analysed to investigate the significant impact of the roll-out of future 5G mobile networks. DWG2: PHY Layer
TD(19)09042 An Agile Full-Duplex 5G Testbed for OTA Testing at 28 GHz: from GbE-based to OTA Live Streaming of 8 HD Videos Rodolfo Gomes, Carlos Ribeiro, Luis Duarte, Telmo Fernandes, Akram Hammoudeh, Manuel Garcia Sanchez and Rafael Caldeirinha This Technical Document (TD) aims to report on recent advances [1,2] of our group on a complete end-to-end 5G testbed fully reconfigurable based on FPGA design, with a 1GHz baseband processing ready for a 8×8 MIMO, and its extension and miniaturisation to 28GHz. Initial results of real-time over-the-air (OTA) 5G mmWave testbed demonstration, including both generation of new waveforms (baseband) and the design of novel RF front-ends at 28 GHz, providing a system throughput up to 16 Gbps, will be presented. The testbed has been designed as a real-time agile FPGA based platform based on Software-Defined-Radio (SDR) concept, enabling on-the-fly digital modulations up to 1024-QAM [IP TWEVO, Lda]. Particular features will be presented, which includes, but not limited to, the design of novel digital signal processing algorithms (in baseband) to mitigate impairments induced by the radio channel, IQ imbalances, Doppler (CFO) effect and channel estimation (with aid of both pilots and sequences), in addition to 8 x 8 MIMO-OFDM architecture easily scalable to support (MASSIVE) MIMO configurations (32 x 32). [1] R. Gomes, L. Sismeiro, C. Ribeiro, T. Fernandes, M. Sanchez, Akram Hammoudeh, R. F. S. Caldeirinha, Will COTS RF front-ends really cope with 5G requirements at mmWave?, IEEE Access, Vol. 6, No. -, pp. 38745 – 38769, July, 2018. [2] R. Gomes, L. Sismeiro, R. F. S. Caldeirinha, C. Ribeiro, M. Sanchez, Akram Hammoudeh, A mmWave solution to provide wireless Augmented Reality in classrooms, International Symposium on Wireless Communication Systems ISWCS, Lisbon, Portugal, Vol., pp. -, August, 2018. EWG-OTA: Over-The-Air testing
TD(19)09043 Agile Radio Channel Sounder for 5G Propagation Modelling at mmWave Frequencies Rafael Caldeirinha, Nuno Leonor, João Reis, André Sardo, Luis Duarte, Glaucio Ramos and Carlos Ribeiro This TD presents an agile and low-cost radio channel sounder based on the cross-correlation properties of pseudo-noise (PN) random sequences, identified in the literature as a swept time delayed cross-correlation (STDCC) channel sounder, also commonly named as a sliding correlation sounder. This sounder enables the characterisation of highly dynamic doubly selective channels, providing both amplitude and Doppler spectra information for each tap of the power delay profile (PDP). It performs real time measurements of specific radio channels with a high resolution of 1ns for adjacent multipath components (MPC’s), and a current maximum Doppler spread of ±1kHz. The amplitude measurements given by the sounder, shown as PDPs, have a dynamic range of about 60 dB. This TD provides detailed information on the most relevant components used to develop the sounder, particular on the newest baseband implementation on a low-cost FPGA, and presents some of the calibration measurements performed on the bench, as well as specific RF measurements at 18, 28 and 60 GHz in several indoor scenarios. DWG1: Radio Channels
TD(19)09044 SDR-based Gateway for IoT and M2M Applications Cristinel Gavrilă, Csaba Kertesz, Marian Alexandru, Vlad Popescu and Titus Bălan Affordable low-power, short-range terrestrial communications are the current enabler for Internet of Things (IoT) and Machine to Machine (M2M) applications. Their main drawback resides in the need of a gateway that enables them to communicate with the world. Satellite gateways have become in the recent years more affordable, but nevertheless, the combined equipment and access costs are still prohibitive for large scale deployments of satellite applications. The goal of this paper is to describe a fully functional prototype for a low-cost satellite gateway based on an embedded Software Defined Radio (SDR) platform. The developed prototype, implemented as a standalone RF platform, will be able to route data between the satellite and M2M/IoT applications, covering on the terrestrial side the most common short range wireless protocols and standards (802.11b/g/n, ZigBee, BLE, etc.). The satellite link will be assured by adapting typical lightweight uplink and downlink protocols, already implemented and tested. This paper is focused on the terrestrial side implementation and experimental results. EWG-IoT: Internet-of-Things
TD(19)09045 Reconfigurable IoT Gateway Based on a SDR Platform Cristinel Gavrilă, Csaba Kertesz, Marian Alexandru, Vlad Popescu and Titus Bălan The current enabler for Internet of Things (IoT) are short-range terrestrial communications embedded on affordable, low-power wireless devices that have as their main drawback the necessity to be connected to a specific gateway that enables them to communicate with the world. The variety of communication standards which are currently used in the IoT world, poses difficulties for having a single device able to act as a gateway for the most important wireless standards. A Software Defined Radio (SDR) platform can be a perfect solution for a single, reconfigurable device. The paper proposes a general architecture for an IoT Gateway and describes the implementation of the architecture as a fully functional prototype for a IoT gateway based on an embedded SDR platform. The developed prototype, implemented as a standalone RF platform, is able to route data to and from M2M/IoT applications, covering the most common short-range wireless protocols and standards (802.11b/g/n, ZigBee, BLE, LoRa, etc). By implementing the above-mentioned wireless protocols on a SDR platform and using its RF capabilities together with a sniffing procedure, these wireless protocols can be detected by the SDR gateway and subsequently communication can be configured to enable transmission between the end devices and external infrastructure, using IP-based packet communication through the means of an MQTT broker. A control interface manages all the gateway activities, provides statistics and ensures human intervention in the system. EWG-IoT: Internet-of-Things
TD(19)09046 Joint High-Resolution Delay-Doppler Estimation for Bi-static Radar Measurements Michael Döbereiner, Martin Käske, Andreas Schwind, Carsten Andrich, Philip Wendland, Guenter Schaefer, Matthias A. Hein, Reiner S. Thomä, Giovanni Del Galdo This contribution describes a maximumlikelihood based joint delay-Doppler estimation algorithm for bi-static radar measurements. The estimator uses a data model regarding delay and Doppler of multiple propagation paths. The transmit signal is rather long, as it is emulating communication signals. Therefore, Doppler has to be modeled as a linear changing phase within a single symbol. The derivation of an iterative Gauss-Newton algorithm to solve the resulting least-mean-squares problem is shown. The model order is determined dynamically by means of the Fisher information matrix and the Cramér-Rao lower bound. The functionality is shown using measurements of a bi-static radar in a semi-anechoic chamber. DWG1: Radio Channels,DWG2: PHY Layer,Localisation and Tracking
TD(19)09047 The importance of far field effect in diffraction at mmWave T. W. C. Brown, M. Khalily Diffraction modelling at mmWave has been found to require new parameters to accurately model the loss around a single or multiple edges. This work will present measurements based on diffraction around one and two edges whereby it will show the importance of incorporating antenna pattern effects as seen in other studies but also more importantly the impact of the Rayleigh far field distance when it is not negligible in comparison with the source to diffracting object distance. DWG1: Radio Channels
TD(19)09048 Kinetic approach for estimation of SIR time-dependent measures in D2D connectivity Anastasia Ivchenko, Yuri Orlov, Andrey Samouylov, Dmitri Molchanov, Yuliya Gaidamaka, Konstantin Samouylov, Luis M. Correia Attempting to build a uniform theory of mobility-dependent characterization of wireless communications systems, in this paper, we address time-dependent analysis of the signal-to-interference ratio (SIR) in device-to-device (D2D) communications scenario. We first introduce a general kinetic- based mobility model capable of representing the movement process of users with a wide range of mobility characteristics including conventional, fractal and even non-stationary ones. We then derive the time-dependent evolution of mean, variance and coefficient of variation of SIR metric. We demonstrate that under non-stationary mobility behavior of communicating entities the SIR may surprising-ly exhibit stationary behavior. DWG3: NET Layer
TD(19)09049 High-Performance Ray-Tracing Simulation Platform for 5G and Beyond Danping He, Ke Guan, Bo Ai, Zhangdui Zhong, Longhe Wang,Thomas Kürner The application scenarios and requirements are more diverse in the fifth-generation (5G) era than before. In order to successfully support the system design and deployment, accurate channel modeling is important. Ray-tracing (RT) based deterministic modeling approach is accurate with detailed angular information and is a suitable candidate for predicting time-varying channel and multiple-input multiple-output (MIMO) channel for various frequency bands. However, the computational complexity and the utility of RT are the main concerns of users. Aiming at 5G and beyond wireless communications, this paper presents a comprehensive tutorial on the design of RT and the applications. The role of RT and the state-of-the-art RT techniques are reviewed. The features of academic and commercial RT based simulators are summarized and compared. The requirements, challenges, and developing trends of RT to enable the visions are discussed. The practices of the design of high-performance RT simulation platform for 5G and beyond communications are introduced, with the publicly available high-performance cloud-based RT simulation platform (CloudRT) as the main reference. The hardware structure, networking, workflow, data flow and fundamental functions of a flexible high-performance RT platform are discussed. The applications of high-performance RT are presented based on two scenarios, i.e., a sub-6 GHz urban scenario and a 28 GHz railway scenario. This TD will be useful for researchers who work on RT algorithms development and channel modeling to meet the evaluation requirements of 5G and beyond technologies. DWG1: Radio Channels
TD(19)09050 Towards Realistic High-Speed Train Channels at 5G Millimeter-Wave Band: Case Study for Paradigm Implementation Ke Guan, Bo Ai, Bile Peng, Danping He, Guangkai Li, Jingya Yang, Zhangdui Zhong, Thomas Kürner In this TD, we present two case studies for generating realistic high-speed train (HST) channels at fifth-generation (5G) millimeter-wave (mmWave) band. The first one is the tunnel environment at relatively low 5G mmWave band, 30 GHz band, while the second one is the outdoor HST environment at the relatively high 5G mmWave band, 90 GHz band. Both case studies include the following steps: ray-tracing simulations, stochastic channel modeling and realization, verification with ray-tracing simulations, and validation with a reduced set of measurements. A profound and insightful conclusion is reached that by employing the proposed paradigm, realistic channels can be realized for the design and evaluation of 5G mmWave communication systems in high-speed railways, even without the support of sufficient channel sounding data. DWG1: Radio Channels
TD(19)09051 Radar Cross Section measurements of the diverse drone models Vasilii Semkin, Jaakko Haarla, and Ville Viikari In this work, we present the quasi-monostatic Radar Cross Section measurements and simulations of different Unmanned Aerial Vehicles at 26-40 GHz. We study the Radar Cross Section signatures of 6 different multirotor platforms and Lithium-ion Polymer batteries. The obtained results provide the considerable information which can be utilized for the superior drone detection at millimeter-wave frequencies. The results reveal how the radio waves are scattered by different sized drones and what is the material impact on the received Radar Cross Section signatures. Obviously, larger drones made of carbon fiber are easier to detect, while the drones made from plastic and styrofoam materials are less visible by the radars. The measurement results correspond well with the simulated ones and can be utilized as a database for the substantial drone detection. DWG1: Radio Channels
TD(19)09052 Low-Rank Channel Estimation for Multiple Antenna Systems using Joint Spatial-Temporal Covariance Matrix Kun Chen-Hu, Dirk T.M. Slock and Ana Garcia Armada Channel estimation is a challenging process in multiple antenna systems. In this procedure, not only it is necessary to obtain the multi-path channel response (fading coefficient and delay of each tap), but it also requires the full characterization of the antenna array response and the multiple radio-frequency chains. In the literature, a realistic approach is given by assuming that spatial features are completely unknown (non-parametric estimation of spatial response), where channel calibration is not required; and it only estimates the joint effects of the frequency selective channel with the known shape of the transmitter and receiver pulses. Additionally, when the noise is considerably high, a low-rank(LR) version of the estimated channel provides a better performance than the full-rank one, in terms of mean square error (MSE). However, one of the most used approximation channel model is to treat independently the spatial and temporal covariance matrices of the channel, where it considerably degrades the overall performance. In our work, we propose an alternative way to characterize the LR estimated channel using a joint spatial-temporal covariance matrix combined with a low-complex delay estimation technique. Moreover, we propose an automatic rank-selector based on the MSE. Numerical results show that our proposal provides a better performance than other proposed in the literature. DWG2: PHY Layer
TD(19)09053 Evaluating Vehicular Antennas for Cellular Radio Communications Nils Dreyer, Gerald Artner , Frank Backwinkel , Frank Wollenschläger , Thomas Kürner Cellular connectivity plays an important role for the present vehicle development. An internet connection based on a 4G network can offer new services as entertainment (media streaming) or traffic information for improved navigation. These services imposes different requirements on the radio link. Testing and developing new antenna designs is challenging and expensive. An open question is the evaluation of different antennas within a realistic environment. In this paper we will introduce an Antenna Scoring Factor (ASF) to compare vehicular antennas and estimate its performance. This approach can be either applied on measured data or simulation results. The indicator can help making decisions on the type of integrated antenna to guarantee throughput as well as network coverage. EWG-OTA: Over-The-Air testing
TD(19)09054 Sparsity in the Delay-Doppler Domain for Measured 60 GHz Vehicle-to-Infrastructure Communication Channels Herbert Groll, Erich Zöchmann, Stefan Pratschner, Sebastian Caban, Martin Lerch, Daniel Schützenhöfer, Markus Hofer, Jiri Blumenstein, Seun Sangodoyin, Thomas Zemen, Ales Prokes, Andreas F. Molisch, Christoph F. Mecklenbräuker We report results from millimeter wave vehicle-to-infrastructure (V2I) channel measurements on Sep. 25, 2018 in an urban street environment, down-town Vienna, Austria. Measurements of a frequency-division multiplexed Multiple-Input Single-Output channel have been acquired with a time-domain channel sounder at 60 GHz with a bandwidth of 100 MHz and a frequency resolution of 5 MHz. Two horn antennas were used on a moving transmitter vehicle: one horn emitted a beam towards the horizon and the second horn emitted an elevated beam at 15° up-tilt. This configuration was chosen to assess the impact of beam elevation on V2I communication channel characteristics: propagation loss and sparsity of the local scattering function in the delay-Doppler domain. The measurement results within urban speed limits show high sparsity in the delay-Doppler domain. DWG1: Radio Channels
TD(19)09055 Some more results on MANET radio performances using the EMANE framework Jean-Frédéric Wagen, Alexandre Nikodemski, François Buntschu and Gérôme Bovet This contribution is a follow-up of TD(18)08034. More results are presented to investigate the performance results (Round Trip Time and Packet Completion Ratio) of a 24-nodes MANET using TDMA radios and OLSR in a real time emulator based on the open-source EMANE framework. DWG3: NET Layer
TD(19)09057 Modulation Based Energy Harvesting Scheme Akashkumar Rajaram, Dushantha Nalin K. Jayakody and Rui Dinis Due to the rapid growth of IoT and other connected devices, developing batteryless and/or self-sustainable devices to enable green communication is crucial. This letter presents an novel, practical simultaneous wireless information and power transfer (SWIPT) scheme based on constellation points within an M-QAM modulation technique MS . This significantly improves the performance of SWIPT associated communication systems. In this work, we employ a hybrid constellation shaping system (HCS) to improve the spectral efficiency. We also compare our proposed scheme with the traditional power splitting scheme based SWIPT PS technique. We demonstrate that our proposed scheme outperforms the PS in terms of error rates and the amount of energy harvested, as compared to traditional SWIPT. DWG2: PHY Layer
TD(19)09058 Fading channel emulation for massive MIMO testing using a conductive phase matrix setup Pekka Kyösti, Petteri Heino Functionalities, algorithms, and performances of massive MIMO base stations are desirable to test in versatile fading radio channel conditions. Base stations of 5G “New radio” that operate on sub 6Ghz frequency bands typically provide antenna connectors enabling RF cable connection of test devices to the device under test (DUT). Furthermore, the number of DUT antennas is high and consequently the need of fading channel emulator (CE) resources becomes high. An approach can be taken to reduce the number of independent fading channels to be emulated. This can be done by using a phase shifting and combining unit (aka phase matrix unit) in between the DUT and CE. The phase matrix concept in fading emulation, together with its capabilities and limitations, is discussed in this TD. DWG1: Radio Channels,EWG-OTA: Over-The-Air testing
TD(19)09059 Investigation on Stationarity of V2V Channels in a Highway Scenario Daniel Czaniera, Martin Käske, Gerd Sommerkorn, Christian Schneider, Reiner S. Thomä, Giovanni Del Galdo, Mate Boban, Jian Luo This contribution investigates the stationarity of the vehicle to vehicle (V2V) channel in terms of distance and time. Due to high inherent mobility, the channel can not be assumed to follow the wide sense stationary (WSS) and uncorrelated scattering (US) assumption. Therefore, new evaluation methods have to be applied. We assess the stationarity for a V2V highway scenario using the generalized local scattering function (GLSF) and its collinearity based on measurements. We compare results for exemplary traffic situations and investigate the influence of the antenna placements on the stationarity of the channel. Our results yield a strong relation between the stationarity time and the change and rate-of-change of distance between transmitter and receiver. DWG1: Radio Channels,DWG2: PHY Layer
TD(19)09060 Numerical methods for random rough surface scattering computation Conor Brennan, Dublin City University, Ireland Dung Trinh-Xuan, Ho Chi Minh City University of Technology ,Vietnam. Vinh Pham-Xuan Ho Chi Minh City University of Technology ,Vietnam and Technische Universitat Darmstadt, Germany Accelerated method of moments techniques are applied to compute EM scattering from randomly rough surfaces with Gaussian or exponential roughness parameters. In conjunction with a suitable iterative solver full wave results can be rapidly generated. The TD examines the algorithm’s performance against roughness parameters, material composition etc. DWG1: Radio Channels
TD(19)09061 OFDM Waveform for Distributed Radar Sensing in Automotive Scenarios Steffen Schieler, Christian Schneider, Andreas Schwind, Philip Wendland, Carsten Andrich, Michael Döbereiner, Jian Luo, Reiner S. Thomä, Giovanni Del Galdo In this paper, an orthogonal frequency-division multiplexing (OFDM) waveform radar sensing approach is demonstrated based on field measurements at C-band. We demonstrate a concept, that is based on the exploitation of typical wireless communication transmissions to perform passive, distributed radar sensing. Our concept is based on an OFDM radar that operates in the modulation symbol domain and can be well integrated into existing OFDM receivers. The measurement setup and the signal processing steps for the OFDM radar are described. The results show that the passive, distributed radar sensing approach can be used to detect moving cars and even pedestrians in automotive intersection scenarios. DWG1: Radio Channels,DWG2: PHY Layer
TD(19)09062 Accuracy Bounds for Array-Based Positioning in Dense Multipath Channels Thomas Wilding, Stefan Grebien, Ulrich Mühlmann, Klaus Witrisal The accuracy of radio-based positioning systems will be limited by multipath interference in realistic application scenarios. This paper derives closed-form expressions for the Cramer-Rao lower bound (CRLB) on the achievable time-of-arrival (ToA) and angle-of-arrival (AoA) estimation-error variances, considering the presence of multipath radio channels, and extends these results to position estimation. The derivations are based on channel models comprising deterministic, specular multipath components as well as stochastic, diffuse/dense multipath. The derived CRLBs thus allow an evaluation of the influence of channel parameters, the geometric configuration of the environment, and system parameters such as signal bandwidth and array geometry. Our results quantify how the ToA and AoA accuracies decrease when the signal bandwidth is reduced, because more multipath will then interfere with the useful LoS component. Antenna arrays can (partly) compensate this performance loss, exploiting diversity among the multipath interference. For example, the AoA accuracy with a 16-element linear array at 1 MHz bandwidth is similar to a two-element array at 1 GHz, in the magnitude order of one degree. The ToA accuracy, on the other hand, still scales by a factor of 100 from the cm-regime to the m-regime because of the dominating influence of the signal bandwidth. The position error bound shows the relationship between the range and angle information under realistic indoor channel conditions and their different scaling behaviors as a function of the anchor-agent placement. Specular multipath components have a maximum detrimental influence near the walls. It is shown for an L-shaped room that a fairly even distribution of the position error bound can be achieved throughout the environment, using two anchors equipped with 2-by-2-array antennas. The accuracy limit due to multipath increases from the 1-10-cm-range at 1 GHz bandwidth to the 0.5-1-m-range at 100 MHz. Localisation and Tracking
TD(19)09063 Single-Anchor, Multipath-Assisted Indoor Positioning with Aliased Antenna Arrays Thomas Wilding, Stefan Grebien, Erik Leitinger, Ulrich Mühlmann, Klaus Witrisal Highly accurate indoor positioning is still a hard problem due to interference caused by multipath propagation and the resulting high complexity of the infrastructure. We focus on the possibility of exploiting information contained in specular multipath components (SMCs) to increase the positioning accuracy of the system and to reduce the required infrastructure, using a-priori information in form of a floor plan. The system utilizes a single anchor equipped with array antennas and wideband signals to separate the SMCs. We derive a closed form of the Cramer-Rao lower bound for array-based multipath-assisted positioning and examine the beneficial effect of spatial aliasing of antenna arrays on the achievable angular resolution and as a direct consequence onto the positioning accuracy. It is shown that ambiguities, arising due to the aliasing, can be resolved by exploiting the information contained in SMCs. The theoretic results are validated by simulations. Localisation and Tracking
TD(19)09065 Measurements and Modeling for indoor to outdoor channels in TVWS Bands Tunçer Baykaş, Mohamed Hashir Syed In this work, we present a measurement campaign results for indoor to outdoor channel modeling for TVWS bands. Our results show that there are distinct shadowing zones. We provide a two tier modeling concept. DWG1: Radio Channels
TD(19)09066 Statistical Evaluation of Delay and Doppler Spread in 60 GHz Vehicle-to-Vehicle Channels During Overtaking Erich Zöchmann, Markus Hofer, Martin Lerch, Jiri Blumenstein, Seun Sangodoyin, Herbert Groll, Stefan Pratschner, Sebastian Caban, David Löschenbrand, Laura Bernadó, Thomas Zemen, Ales Prokes, Markus Rupp, Christoph Mecklenbräuker, Andreas Molisch Millimeter waves experience much higher maximum Doppler shifts than their centimeter wave counterparts. We measured the wireless channel of 36 different overtaking vehicles to obtain delay and Doppler spread values based on ensemble averages. Our TX antenna is a horn with an 18 degree half power beam width. Spatial filtering by this narrow beam decreases the delay and Doppler spread values. We observe that the RMS Doppler spread is effectively below one-tenth of the maximum Doppler shift. For example, at 60 GHz a relative speed of 30 km/h yields a maximum Doppler shift of approximately 3.3 kHz and a median RMS Doppler spread of 220 Hz at the utmost. The largest median RMS delay spread observed is 5.3 ns. DWG1: Radio Channels
TD(19)09067 Gaussian Process Modeling of UWB Multipath Components Anh Nguyen Hong, Michael Rath, Josef Kulmer, Stefan Grebien, Erik Leitinger, Khang Nguyen Van, and Klaus Witrisal In the field of radio channel modelling, the consideration of ultra-wideband (UWB) signals allows for a channel description that can be decomposed into deterministic multipath components (MPCs) and dense / diffuse multipath. In this paper, deterministic MPCs are studied. A Gaussian Process (GP) model is used as a regression tool to analyze and model the MPC amplitude behavior, based on channel measurements. In this regard, the dependency of the amplitude on the incident angle of the signal at a reflecting surface is analyzed. The channel model is related to kernel functions used in GP that describe the similarities between different data points. Based on the model parameters, the amplitudes of MPCs are predicted at other positions of the receiver that have not been measured in the experiment. The method can then be used to predict a UWB channel impulse response at an arbitrary position in the environment. DWG1: Radio Channels,Localisation and Tracking
TD(19)09068 From Iterative Threshold Decoding to a Low-Power High-Speed Analog VLSI Decoder Implementation Werner G. Teich Two of the key capabilities of the fifth generation (5G) of cellular mobile communication systems are increased peak and network data rates and an energy efficient operation. Signal processing plays an important role to meet these goals. Recently it has been shown that signal processing with analog electronic circuits has a large potential for a high-speed and energy efficient operation. In this paper we consider the problem of decoding. Specifically we designed and realized an iterative threshold decoder for self-orthogonal convolutional codes. We report on a student project where we used standard of-the-shelf electronic components to realize the analog decoder circuit. Starting point is the iterative threshold decoder, the structure of which corresponds to the structure of a high-order recurrent neural network (HORNN). Thus the structure as well as the weights of this HORNN are defined by the problem. A training phase is not required. The dynamics of the HORNN can be implemented in discrete-time, this corresponds to the iterative threshold decoder, or in continuous-time. Both implementations lead to the same asymptotic state, which corresponds to the decoder output. The dynamical evolution of the continuous-time HORNN is governed by a set of first-order differential equations. Based on that we find an analog electronic circuit which shows a similar dynamical evolution as the continuous-time HORNN, and therefore also the same asymptotic state. DWG2: PHY Layer
TD(19)09069 Measured Delay and Doppler Profiles of Overtaking Vehicles at 60 GHz E. Zöchmann, C.F. Mecklenbräuker, M. Lerch, S. Pratschner, M. Hofer, D. Löschenbrand, J. Blumenstein, S. Sangodoyin, G. Artner, S. Caban, T. Zemen, A. Prokeš, M. Rupp and A.F. Molisch We report results from real-world millimetre wave vehicle-to-vehicle channel measurements carried out in an urban street environment, down-town Vienna, Austria. Channel measurements have been acquired with a time-domain channel sounder in the frequency band 59.75-60.25 GHz with a frequency resolution of approximately 5 MHz. We estimate the local scattering function for sequential stationarity regions in time. A multitaper estimator is used to precisely define Doppler and delay resolutions. Estimates for delay and Doppler profiles are evaluated from the local scattering function for several overtaking vehicles at a variety of speeds and for different types of vehicles. The results show that passenger cars are associated with a single Doppler trajectory, whereas larger vehicles, such as trucks, show up in the data with multiple Doppler trajectories. DWG1: Radio Channels
TD(19)09070 TRUDI: Testing Environment for Vehicular Applications Running with Devices in the Loop Michele Menarini, Pasquale Marrancone, Giammarco Cecchini, Alessandro Bazzi, Barbara M. Masini, Alberto Zanella Vehicles will be equipped with short-range wireless technologies with the aim to improve safety and traffic efficiency. Novel applications are thus being implemented for future cars and trucks, and one of the main issues is how to conduct tests and optimizations in an effective way, limiting the need to perform costly and time consuming experiments on the road. To cope with this issue, we have implemented a simulator with hardware in the loop, called TRUDI, where the hardware and the implemented applications are tested in the laboratory by injecting virtual positions of the vehicles with the support of a traffic simulator. TRUDI acts as a man-in-the-middle between the communication module and the application itself, making it possible to perform tests with the real devices and providing as an output a system ready for the road. To evaluate more complex scenarios, it is also possible to reproduce the presence of others connected vehicles thanks to the traffic simulator. As an example use case, an application for the intersection management, where the driver is warned of the presence and speed of other vehicles approaching the same junction, is presented. DWG3: NET Layer,EWG-IoT: Internet-of-Things
TD(19)09071 UWB Path Loss Models for Ingestible Devices Sofia Perez-Simbor, Carlos Andreu, Concepcion Garcia-Pardo, Matteo Frasson, Narcis Cardona Currently, some medical devices such as the Wireless Capsule Endoscopy (WCE) are used for data transmission from inside to outside the body. Nevertheless, for certain applications such as WCE, the data rates offered by current medical frequency bands can result insufficient. Ultra Wideband (UWB) frequency band has become an interesting solution for this. However, to date, there is not a formal channel path loss model for the UWB frequency band in the gastrointestinal (GI) scenario due to the huge differences between the proposed studies. There are three main methodologies to characterize the propagation channel, software simulations and experimental measurements either in phantom or in in vivo animals. Previous works do not compare all the methodologies or present some disagreements with the literature. In this paper, a dedicated study of the path loss using the three methodologies aforementioned (simulations, phantoms and in vivo measurements) and a comparison with previous researches in the literature is performed. Moreover, numerical values for a path loss model which agrees with the three methodologies and the literature are proposed. This paper aims at being the starting point for a formal path loss model in the UWB frequency band for WBANs in the GI scenario. SEWG-IoT: Internet-of-Things for Health
TD(19)09072 Characterisation of Channel Hardening Using the Diversity Order of the Effective Channel Jens Abraham , Golsa Ghiaasi, Torbjorn Ekman Massive MIMO promises beneficial properties of large scale antenna systems at a cellular base station. Increased sum capacity and robustness are potential gains to be harvested by increasing the number of base station antennas towards infinity. This contribution uses the effective channel in the downlink to analyse properties of channel hardening (spectral and spatial diversity) for a limited number of antennas. The average effective gain for a reference channel is derived to allow insight into the distribution of small scale fading. Radio channel measurements on four frequency bands are used to exemplify the effective diversity order with respect to the reference channel. Comparing a single antenna with a 16 antenna base station shows increasing utilisation of spatial diversity. The effective channel allows modelling of outage probabilities, offering a tradeoff between the severity of fading and the number of antennas. DWG1: Radio Channels
TD(19)09073 RF Domain Symbol Level Precoding for Large-Scale Antenna Array Systems Stavros Domouchtsidis, Christos Tsinos, Symeon Chatzinotas, Bjorn Ottersten In this paper we consider two transmitter designs for symbol-level-precoding (SLP), a technique that mitigates multiuser interference (MUI) in multiuser systems by designing the transmitted signals using the Channel State Information and the information-bearing symbols. The considered systems tackle the high hardware complexity and power consumption of existing SLP techniques by reducing or completely eliminating fully digital Radio Frequency (RF) chains. In these architectures, which we refer to as RF domain SLP, the processing happens entirely in the RF domain, thus eliminating the need for multiple fully digital RF chains altogether. Instead, analog phase shifters directly modulate the signals on the transmit antennas. The precoding design for all the considered cases is formulated as a constrained least squares problem and efficient algorithmic solutions are developed via the Coordinate Descent method. Simulations provide insights on the power efficiency of the proposed schemes and the improvements over the fully digital counterparts. DWG2: PHY Layer
TD(19)09074 Modelling the first path delay in UMa scenario for positioning estimation Satyam Dwivedi, Jonas Medbo Channel models typically used in wireless system/algorithm evaluation do not have information about the time of flight of the path the signal traverses from a transmitter to a receiver. This information is not of much significance in the communication systems, as they are designed today. However, in wireless position estimation problems this information is necessary. This information gives an estimate of the distance between transmitter and receiver nodes. Or, provides useful geometric information for positioning purposes. In this technical document (TD), we will discuss a model based on measurement data to model the time of flight between a transmitter and receiver in an urban environment in a TDOA based positioning system. Localisation and Tracking
TD(19)09075 From Nanocommunications to Body Area Networks: a Perspective on Truly Personal Communications Pawel Kulakowski, Kenan Turbić and Luis M. Correia This paper presents an overview of the problems related to really personal communications in a future perspective, i.e., ranging from communications inside the human body, to communication from a device on the human body to the outside environment. On the one hand, nanocommunications, understood as molecular communications (those performed in between groups of molecules or cells) will enable a range of applications that definitely will capture the attention of medical doctors, among others. The increase in scale will go through communication with nanodevices inside the body, followed by in-body communications (from these nanodevices to on-body ones), and then on-, off- and body-to-body communications (which address communication among devices on the body, and from these devices to external ones, being on the outside environment in general or on the body of another person). This paper intends to show how this gap can be closed by introducing proper interfaces, and also by referring some potential applications. SEWG-IoT: Internet-of-Things for Health
TD(19)09076 Moving interference source prediction for millimetre wave mesh network János Bitó Monitoring network performance makes it possible to give an estimation or prediction on future runoff of the disturbing effects, so that these effects can be eliminated to a certain degree. This TD aims to study moving interference source disturbing a millimetre wave mesh network and prediction possibilities of these effect, keeping an eye on the fact that it is possible to prepare the network for known disturbances, and with that it is possible to decrease energy consumption of the network. DWG1: Radio Channels
TD(19)09077 A Real-Time Propagation Channel Sounder for 5G Applications Jean-Marc Conrat this paper describes a wideband radio channel sounder. Such a device is able to measure the complex time-variant impulse response of the propagation channel. The impulse response is obtained by inversion of an optimal multi-sine sequence with flat spectrum and low crest factor. In standard configuration, this device is able to measure the propagation channel impulse response with a maximum bandwidth of 800 MHz in the DC-30 GHz frequency range fulfilling 5G requirements especially for millimeter wave frequencies. The receiver digital part is based on a PCIe 3 Gs/s 12-bit digitizer implementing efficient data streaming functions. The measurement software is a C/C++ Windows 10 application and uses advanced optimization technologies such as vectorization or multi-threading making possible real-time operations. The simultaneous transfer function on two channels is acquired, processed and saved in less than 100 µs. RF and digital parts have been simplified in order to reduce the form factor, the weight, the power consumption and maintenance issues. DWG1: Radio Channel
TD(19)09079 On scattering and specular reflection formulations for modelling using point cloud maps Jean-Frederic Wagen A series of contributions TD(16)01060, TD(17)04025,TD(17)05044, TD(18)06045, TD(18)07032 investigated the use of single order scattering and specular reflection formulations for modelling using point cloud maps. So far two formulations, one for rough scattering and one for specular reflection were used. An attempt is presented here to compute the scattering and specular reflection components using a single formulation. DWG1: Radio Channels
TD(19)09080 Implementation of Array Antenna Systems with MIMO Rooderson Martines de Andrade, Fernando J. Velez, Kun Chen and Ana Garcia Armada Multiple input and multiple output (MIMO) technology is able to offer a large increase in the capacity of 5G systems, without requiring a considerable increase in bandwidth or power required for transmission. This work starts by presenting an overview of the concepts from MIMO systems. Combined with millimetre waves (mmWaves) technology, massive MIMO systems, where the number of antennas in the base station and the number of users are large, is a promising solution for 5G. In this work, SDR implementations have been performed considering a platform with Matlab code applied to MIMO 2×2 implemented with Universal Software Peripheral Radios (USRPs). Complex structures of MIMO systems can be simplified by using mathematical methods implemented in Matlab for the synchronization of the USRP in the receiver side. SISO transmission and reception techniques have been considered to refine the synchronization (with 16-QAM), thus facilitating the implementation of the MIMO system. Together with the practical MIMO, this type of solution is the starting point for future hardware building blocks involving massive MIMO systems. As a future work, a more complex system will be implemented, as well as the use of a MIMO multi-antenna system with USRP hardware, to which it is possible to synchronize a 4×4 MIMO system using a single platform in Matlab to explore completely multi-user MIMO techniques. DWG1: Radio Channels,DWG3: NET Layer
TD(19)09081 Mapping between the Average SINR and the Supported Throughput in Small Cell HetNets Bruno C. Silva and Fernando J. Velez This work gives contributions on fundamental aspects of the mapping between the average SINR and the supported throughput in a context of Small Cell HetNets operating at 2.6 GHz and 3.5 GHz. The average SINR has been analytically studied for different values of the transmitter power. We have been able to conclude that Average SINR does not depend of the transmitter power and that it has the same values at 2.6 GHz and 3.5 GHz frequency bands up to a cell radius of circa 50 m. Then, when the cell radius is longer than 50 m, the supported throughput at 2.6 GHz is higher than at 3.5 GHz. By analyzing the results we can conclude that there is a correspondence between the average SINR and the supported throughput through a transformation defined by the table of the LTE Advanced modulation and coding schemes. As 5G will also consider OFDM, it is expected that the principles and lessons learned from analysing the optimization the trade-off of 4G networks will remain. DWG3: NET Layer
TD(19)09082 Update on the Evaluation of Source Routing Minimum Cost Forwarding Protocol over 6TiSCH Applied to the OpenMote-B Platform Anderson Rocha Ramos, Fernando José Velez and Gordana Gardašević This Temporary Document (TD) presents the recent results obtained from the work that have been carried out with the aim of implementing Source Routing Minimum Cost Forwarding (SRMCF) protocol over IPv6 over the TSCH mode of IEEE 802.15.4e (6TiSCH), evaluating the performance of these protocols for the Internet of Things (IoT), and different healthcare, medical monitoring and urban mobility applications. To perform the new experiments presented, this work is making use of the OpenWSN project platform, which implements IEEE 802.15.4e in an open source environment. The evaluation process is also being done in the most recent version of the OpenMote-B platform, considering higher numbers of hop distances and evaluating different parameters, such as packet loss ratio, throughput, Round Trip Time (RTT). Another goal of this research is to give contribution to the investigation of the applicability of quality of service (QoS) applied to the IEEE 802.15.4e standard. In the present stage of development, the efforts are concentrated on the programming of the required code, and the adaptation of the OpenWSN stack. Experimental results have shown that the proposed protocol is capable of reducing Packet Loss Ratio (PLR) and energy consumption in comparison to the Routing Protocol for Low Power and Lossy Networks (RPL). For the SRMCF protocol, the RTT is shorter than for RPL for a number hops lower than four hops. EWG-IoT: Internet-of-Things
TD(19)09083 Using COST IC1004 Vienna Scenario to test C-RAN optimisation algorithms Rolando Guerra, Silvia Ruiz, Mario Garcia-Lozano, Joan Olmos This work is proposes the use of a modified and improved version of the realistic Vienna Scenario that was defined in COST Action IC1004, to test C-RAN deployment. IC1004 scenario includes 233 Mcell sites (628 cells) and has been recently updated to better reflect a dense urban area, by introducing 221 Scells and re-calculating path loss by means of a 3D ray-tracing algorithm. A total of 849 RRHs are assigned to BBUpools following different criteria as minimising delays, balance the load among pools or an efficient clustering of RRH oriented to maximise the multiplexing gain of the pool as well as the mapping of RRHs to BBUs. First results are obtained assuming simple traffic models on a per cell basis. But as the scenario allocates 7000 UEs randomly, it is also possible to simulate different services and traffic patterns, with a realistic estimation of SINRs to get a better distribution of computational resources among BBUs. DWG3: NET Layer
TD(19)09084 Massive MIMO Extensions to the COST 2100 Channel Model: Modeling and Validation Jose Flordelis, Xuhong Li, Ove Edfors, and Fredrik Tufvesson To enable realistic studies of massive multiple-input multiple-output (MaMi) systems, the COST~2100 channel model is extended based on measured MaMi channels. First, the novel concept of a base station (BS)-side visibility region (BS-VR) is proposed to model the appearance and disappearance of clusters along the axis of a physically-large array. Empirically, the number of BS-VRs is Poisson-distributed, and the true BS-VR lifetimes exponentially-distributed; the BS-VR process intensity is then proportional to the sum of the array length and the mean BS-VR lifetime. Simulations suggest that under certain conditions longer BS-VRs can help decorrelating closely-located users. Second, the novel concept of a multipath component (MPC) visibility region (MPC-VR) is proposed to model, at the mobile station side, birth-death processes of individual MPCs. Empirically, true MPC lifetimes are lognormally distributed, as are the radii of the MPC-VRs. If these are applied, simulations of closely-located users are in good agreement with measurement results of the channel condition number, and overestimate it otherwise. Key statistical properties of the proposed extensions, e.g., autocorrelation functions, maximum likelihood estimators of the new model parameters, and Cramer-Rao bounds, are derived and analyzed. DWG1: Radio Channels
TD(19)09085 Spatial Data Focusing using time resources S. Golstein, G. Molineaux, M. Odhiambo, F. Horlin, P. De Doncker, J. Sarrazin The goal of this study is to propose physical solutions that enable the broadcasting of information to specific spatial locations, using limited infrastructures. From a scientific point of view, the problem is to find a way for a base station to wirelessly transmit data that are decodable only within desired areas. To do so, we propose to focus the transmitted data rather than focusing the transmitted power as classically done by antenna arrays. The idea is to process the data in order to be decodable only at predetermined spatial locations. This scheme is spatially more selective than focusing the power and therefore overcomes the classical limitations of beamforming techniques where the antenna arrays have to be large in order to focus the radiated power within a limited-size area. This paper presents an assessment of the robustness of the proposed scheme with respect to different channel conditions. DWG1: Radio Channels
TD(19)09086 “Fog Massive MIMO” for ultra-dense, low latency radio access networks Alister Burr, Dick Maryopi and Manijeh Bashar “Cell-free” massive MIMO is a useful analogue of “Cloud-RAN” for ultra-dense radio access networks (RANs) – however Cloud-RAN can result in large latency, unsuited to many 5G applications, and hence “Fog-RAN” has been proposed, in which the baseband processing is moved from the “cloud” into the “fog”, much closer to the network edge. Here we propose “Fog Massive MIMO” as an analogue of “Fog-RAN”, enabling us to analyse its performance, and in particular the trade-off between latency and capacity. In our model the baseband processing is performed in a set of “edge processing units” (EPUs), which decode data from a relatively small number of user terminals (UTs) within its service area, by processing signals from a cluster of access points (APs) covering a larger coordination region. This implies that there are overlap areas in which APs may be connected to more than one EPU. The UTs within a coordination region use orthogonal pilots. We examine the trade-off between the size of the coordination region and the service area and the signal to interference plus noise ratio, which in turn determines user throughput. DWG2: PHY Layer
TD(19)09087 A Geometry-based Stochastic Channel Model for V2V Intersection Scenarios based on High-resolution Measurements Carl Gustafson, Kim Mahler, David Bolin, Fredrik Tufvesson Vehicle-to-vehicle (V2V) wireless communications can improve traffic safety at road intersections and enable congestion avoidance. However, detailed knowledge about the wireless propagation channel is needed for the development and realistic assessment of V2V communication systems. In this paper, we present a novel geometry-based stochastic MIMO channel model, based on extensive high-resolution measurements at different road intersections in the city of Berlin, Germany. We extend existing models, by including the effects of various obstructions, higher order interactions and by introducing an angular gain function for the scatterers. Scatterer locations have been identified and mapped to measured multi-path trajectories using a measurement-based ray tracing method and a subsequent ransack algorithm. The developed model is parameterized, and using the measured propagation paths that have been mapped to scatterer locations, model parameters are estimated. The time variant power fading of individual multi-path components is found to be best modeled by a Gamma process with an exponential autocorrelation. The path coherence distance is estimated to be in the range of 0-2 m. The model is also validated against measurement data, showing that the developed model accurately captures the behavior of the measured channel gain, Doppler spread and delay spread. This is also the case for intersections that have not been used when estimating model parameters. DWG1: Radio Channels,EWG-IoT: Internet-of-Things
TD(19)09089 Applicability Limits of Simplified Human Blockage Models at 5G mm-Wave Frequencies J. Samuel Romero-Peña, Narcís Cardona (iTEAM Research Institute, Universitat Politècnica de València) This paper analyzes the feasibility of using a simple diffraction model to compute the blocking of the human body to millimeter wave radio frequencies in indoor environments. The model makes a set of approximations that are evaluated in the paper, to determine the applicability limits of such simplified approach to the human body blockage case. The work presented here: (1) describes briefly the mathematical support that is used to model the concealment using the Knife-Edge model, (2) identifies the potential simplifications applicable to the mathematical model implementation that allow a 3D geometric human body to be modelled with simple 2D shapes, (3) characterizes the polarization influence on the mm-wave blocking for such simplified human body models. DWG1, EWG-IoTHealth
TD(19)09090 Channel model developments at 3GPP and implications on device testing Moray Rumney This paper will summarize recent developments at 3GPP regarding the application of the 3GPP channel model in TR 38.901 for < 6 GHz and mmWave frequencies, plus other developments in channel modelling including a new study on indoor industrial IoT for which academic input is required. EWG-OTA, DWG1
TD(19)09091 LoRa Physical Layer Evaluation for Point-to-Point Links and Coverage Measurements in

Diverse Environments

Gilles Callebaut, Guus Leenders, Stijn Crul, Chesney Buyle, Liesbet Van der Perre Applications such as tracking livestock, monitoring the health of trees and environmental parameters, and other Internet of Things (IoT) services are emerging leveraging on Low Power Wide Area Networks. However, many of these applications do not require the complete

network infrastructure of these technologies. By only employing the physical layer, point-to-point links can be set up, easing the installation and lowering the overall cost of these systems. In this paper, the advantages of creating such point-to-point LoRa connections over typical star networks is discussed. The physical layer is evaluated in three distinct environments, i.e., coastal, forest and urban. Our field measurements demonstrate coverage up to 1km with antennas at only 1.5m height in an urban scenario. In free Line-of-Sight (LoS) this coverage is extended to 4 km. The presented heatmap of the received signal strength and signal-to-noise ratio demonstrates the value of LoRa pointto-point connections in these environments. Based on the experimental results, an appropriate path loss model will be derived in future work.

EWG-IoT (and to a lesser extent: DWG2)
TD(19)09092 Building Entry Loss for Traditional and Thermally Efficient Houses Between 0.4 and 73 GHz Jack Lewis Towers, Sana Salous, Xavier Raimundo, and Adnan Cheema This paper presents results of building entry loss measurements into a thermally efficient building and a traditional building between 0.4 and 73 GHz using two custom designed channel sounders developed at Durham University. Comparative measurements indicate that opening external windows reduces the penetration loss by 10 dB in the millimeter wave bands between 25-73 GHz. A difference of ~2-16 dB between the two types of build is measured across the entire frequency range.
TD(19)09093 1-100 GHz Deterministic and Experimental Indoor Channel Modeling Maria-Teresa Martinez-Ingles, Frédéric Challita, Davy P. Gaillot, Juan Pascual García and Jose-Maria Molina-Garcia-Pardo This work presents an empirical analysis of Line-of-Sight (LoS) experimental data from 1 to 100 GHz based on a VNA using three different set-ups in the same indoor scenario. The received power, RMS delay spread, K-factor and correlation, computed from the measured data, provide an insight of how propagation behaves in some possible 5G frequency bands in an indoor environment.