7th MCM – Cartagena, Spain, May 30 – June 1

TD # Title Authors Abstract WGs
TD(18)07001 An Empirical System Loss Model for Body Area Networks in a Passenger Ferry Environment Pawel T. Kosz, Slawomir J. Ambroziak, Jacek Stefanski, Krzysztof K. Cwalina, Luis M. Correia, Kenan Turbic This paper presents a general empirical system loss model for estimating propagation loss in Body Area Networks in off-body communications at 2.45 GHz in a passenger ferry environment. The model is based on measurements, which were carried out in dynamic scenarios in the discotheque passenger ferry environment. The model consists of three components: mean system loss, attenuation resulting from the variable antenna position on the human body, and attenuation due to fading. Preliminary results for system loss components in dynamic scenarios in the discotheque environment are presented. The components of mean system loss and variable antenna position attenuation are modelled by using a linear regression. The obtained root mean square error for the mean system loss is lower than 5 dB. The fading components are modelled by Lognormal and Nakagami-m distributions. SEWG-IoT
TD(18)07002 An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferry Environment Krzysztof K. Cwalina, Slawomir J. Ambroziak, Piotr Rajchowski In the article an off-body narrowband and ultra-wide band channel model for Body Area Networks in a ferry environment is described. A mobile, heterogeneous measurement stand, that consists of three types of devices: miniaturized mobile nodes, stationary reference nodes and a data acquisition server was developed. A detailed analysis of both radio channels parameters in untypical indoor environment was carried out. An analysis of system loss for off-body communication, including mean system loss, slow fading component (corresponding to body shadowing) and fast fading component (associated with the multipath phenomenon), both for the 868 MHz narrowband and for the 6489 MHz ultra-wide band channels, was performed. Obtained system loss exponent values are in the range of [0.13; 0.85] for line-of-sight conditions, and [1.25; 3.46] for non-line-of-sight conditions. For the investigated environment the lognormal distribution was found to be the best describing the slow and fast fading, regardless of the frequency band and on-body antenna placement. A statistical analysis of the model parameters was also carried out and its good matching to the empirical data was proved. SEWG-IoT
TD(18)07003 Mobile Device for Generating Electromagnetic Curtain for Special Applications Piotr Rajchowski, Slawomir J. Ambroziak, Krzysztof K. Cwalina, Jaroslaw Magiera, Pawel T. Kosz In the article the key assumptions, project and laboratory demonstrator of a mobile device for generating an electromagnetic curtain were described. The device is designed for countering the threads of RCIEDs (Radio Controlled Improvised Explosives Devices). During the research work authors build a laboratory demonstrator including software and a hardware layer. DWG1; DWG2
TD(18)07004 Multipath Fingerprints Exploitation to Enhance Localization Performance in TDoA Systems Marcelo Nogueira de Sousa, Reiner Thomä This work introduces a technique to locate radio frequency emitters in none-line-of-sight (NLOS) situation using a combination of ray-tracing simulation, Channel Impulse Estimation, and Machine Learning Tools. The multipath fingerprint information produced by RT simulation together with calibration emitters feeds a Machine Learning engine, which refines the target localization embedding all the reflection and diffraction in the propagation scenario. The simulations done showed the feasibility of the proposed method, provided that the buildings and scenario data can be appropriately included in the estimation of the emitter position. EGW-LT
TD(18)07005 LoRa-like CSS-based PHY layer, capture effect and Serial Interference Cancellation Umber Noreen, Laurent Clavier, Ahcène Bounceur Long Range communications are taking an important place in the IoT world. One Physical Layer solution is LoRa. It is based on Chrip Spread Spectrum. In this paper we review how this modulation technique carries information. However, a simple MAC layer, like ALOHA, will rapidly limit the capacity (in term of number of users) of such networks. However, sensing the channel will not resolve the collision problem because of the very wide coverage of access points. We study how capture effect and even more serial interference cancellation can drastically improve the performance. The position randomness of transmitters can allow to correctly decode simultaneous transmissions. DWG2, EWG-IoT
TD(18)07006 Millimeter Wave Multi-User Performance Evaluation Based on Measured Channels With Virtual Antenna Array Channel Sounder Allan Wainaina Mbugua, Wei Fan, Yilin Ji, Gert Frølund Pedersen Virtual antenna arrays are versatile and cost-effective tools for millimeter-wave channel characterization. Massive sampling of the channel in space with virtual antenna arrays enables high spatial resolution in channel sounding. In this paper, a uniform cubic array is used with a vector network analyzer to characterize an indoor propagation channel. The power angle delay profile under line-of-sight (LOS) and obstructed-LOS (OLOS) scenarios is then extracted from the measurement data. The analysis is extended to a multi-user scenario using a virtual uniform rectangular array, which acts as the base station and with users under LOS and OLOS conditions. Results show interference suppression with zero-forcing beamforming that performs well even in critical multi-user scenarios based on the measured channels, i.e., a scenario with closely spaced users in LOS conditions and a scenario with a strong interfering user and a weak desired user. DWG1
TD(18)07007 Assessment of the Suitability of NB-IoT Technology for ORM in Smart Grids Varun Nair, Remco Litjens, Haibin Zhang We assess the suitability of NB-IoT (Narrowband Internet of Things) cellular technology for smart grid applications, concentrating on the reliable and timely delivery of Outage Restoration & Management (ORM) messages at the event of a local or regional power outage. Using system-level simulations modelling of both the cellular NB-IoT and the energy distribution networks for different environments, we present an extensive sensitivity analysis of the ORM service performance w.r.t. various radio network configurations. In particular, we propose and analyze different packet schedulers, an essential mechanism in optimizing the service performance. A key outcome of the study is the conclusion that indeed NB-IoT is a suitable technology for supporting ORM services in smart grids, accompanied with a proposed near-optimal radio network configuration to best do so. DWG3, EWG-IoT
TD(18)07008 Modelling and Evaluation of Uplink and Downlink KPI Variations using Information Bottleneck and Non-parametric
Hypothesis
Taulant Berisha and Christoph F. Mecklenbräuker In this paper, we evaluated real-world measurements conducted in LTE 1800MHz as well as performed empirical analysis of uplink and downlink key performance indicator (KPI) variations. We consider a measurement setup with user equipments (UEs) located inside and outside of the vehicle under test (VUT), that mimic the quasi-real usage of end users. In this context, the variation of link margin at received power RSRP can be interpreted as the vehicular penetration loss (VPL), which is expected to be comparable to low-multipath environment measurements. Despite of user positions, this variation significantly impacts transmit power, which imposes the UEs to transmit at maximum power 22 dBm on coverage areas with extremely poor service. Initially, we approach the problem of identifying the geographical partitions of various environments by using information bottleneck. Under mobility, the approach enables to asses strong changes at relevance variable. In addition, we apply empirical analysis with non-parametric recursive hypothesis to model the deteriorations of the inside compared to outside of the vehicle UE. DWG2, EWG-OTA
TD(18)07009 Theoretical and Experimental Study at 60 and 94 GHz in Indoor Environments Maria-Teresa Martinez-Ingles, Davy Gaillot, Juan Pascual García, Jose-Maria Molina-Garcia-Pardo, José-Víctor Rodríguez, Leandro Juan Llácer This TD presents an extensive multidimensional analysis of Line-of-Sight experimental data and simulations at two frequency bands: 60 GHz and 94 GHz. MIMO channel transfer functions were obtained with a ray tracing engine that includes single-order diffuse scattering. The received power, RMS delay spread, maximum excess delay and clustering is computed from both measured and simulated data indicate that diffuse scattering improves ray tracing based modeling. The analysis of the results shows that even a raw description of the environment can be used to predict mmW propagation with ray tracing. DWG1
TD(18)07010 Evaluation of an antenna selection strategy for reduced massive MIMO complexity F. Challita, M.Liénard, D.P. Gaillot, M-T. Martinez-Ingles, J-M. Molina-Garcia-Pardo Massive Multiple-Input Multiple-Output (MIMO) is emerging as one of the promising technologies for the fifth generation (5G) systems to improve the radio link reliability, spectrum efficiency, and data rates. Nonetheless, the hardware and software complexity arising from the sheer number of transmitting elements is a bottleneck. The hybrid beamforming massive MIMO architecture, for which the number of radio-frequency (RF) is much smaller than the total number of antennas, has been reported as an appealing solution to this problem but efficient antenna selection strategies are yet to be defined. In this work, a strategy relying on the receiver (Rx) spatial correlation is investigated to select the best antenna subset. It is evaluated from ray-traced massive MIMO radio channels not only at the channel level using propagation metrics, but also at the system level with precoding schemes and sum-rate capacity computations. The results demonstrate that a distributed antenna array configuration with wisely selected antennas outperforms a collocated one for all studied metrics with performance close to the full array. Moreover, the best antenna subset presenting the lowest Rx correlation values maximizes the sum-rate capacity with only a third of the initial RF chain hardware complexity, thus validating the proposed approach. DWG1
TD(18)07011 Flexible Multi-Numerology Systems for 5G New Radio Ahmet Yazar, Huseyin Arslan The physical layer of 5G cellular communications systems is designed to achieve better flexibility in an effort to support diverse services and user requirements. OFDM waveform parameters are enriched with flexible multi-numerology structures. This paper describes the differences between Long Term Evolution (LTE) systems and New Radio (NR) from the flexibility perspective. Research opportunities for multi-numerology systems are presented in a structured manner. Additionally, a novel heuristic method is developed to find the efficient number of multi numerologies. The proposed method aims to control overheads in systems using multi-numerology structures. Finally, inter-numerology interference (INI) results as a function of guard allocation and multi-numerology parameters are obtained through simulation. DWG2
TD(18)07012 Study of coexistence between different services in novel 5G Frequency Bands Claudia Carciofi, Paolo Grazioso, Francesco Matera, Valeria Petrini In this work we show the results of coexistence studies between incumbent systems and the forthcoming 5G networks. The analyses were conducted by means of a simple but rigorous prediction tool and based on the widely adopted Minimum Coupling Loss (MCL) methodology. We considered the three pioneer bands identified to offer 5G services in Europe by 2020 on a large scale: the 700 MHz, the 3.5 GHz and the 26 GHz band, using for each band appropriate propagation models. Results show how coexistence is possible, both on a co-channel and an adjacent channel basis, provided that adequate separation is guaranteed between interfering services. DWG3, EWG-IoT
TD(18)07013 A Map-Free Indoor Localization Method Using Ultrawideband Large-Scale Array Systems Yilin Ji, Johannes Hejselbæk, Wei Fan, Gert F. Pedersen In this paper, we propose a novel map-free indoor localization method using ultrawideband large-scale array systems in high frequency bands. The proposed localization method comprises two stages, namely a channel-estimation stage and a target-localizaiton stage. Due to the large array aperture, the locations of the scatterers associated to the multipath components (MPCs) can be estimated with the spherical wavefront model. The estimated scatterers are further used as virtual anchors to estimate the location of the target through trilateration. Since the scatterer locations are obtained from channel measurements, the map of the environment is not needed for localization. The proposed method is also assessed with measurements conducted in a cluttered indoor environment with line-of-sight (LoS) and non-line-of-sight (NLoS) scenarios. Results show the proposed algorithm attains good localization accuracy in both scenarios. EWG-LT
TD(18)07014 Frequency Dependence of UWB In-Body Radio Channel Characteristics Carlos Andreu, Concepcion Garcia-Pardo, Sergio Castelló-Palacios, Ana Vallés-Lluch and Narcís Cardona In this work, a research of Ultra-wideband (UWB) in-body channel by using a high accurate phantom is performed in order to evaluate the impact of frequency dependence of human tissues on the channel characteristics. Hence, a phantom-based measurement campaign from 3.1 to 5.1 GHz has been conducted. From post-processing data, the path loss is assessed considering subbands of 500 MHz as well as the entire frequency range under test. In addition, the correlation in transmission is computed and discussed. SEWG-IoT
TD(18)07015 PDOA Emitter Location Using Game Engines 3D Ray based Tools Andres Navarro and William Cruz Simulation results of channel parameters using a Game Engine Ray Based Tool for an outdoor scenario are used in this paper to perform the location of a radio emitter. We present simulation results for the localization of a transmitter with NonLine of Sight with two receivers using hybrid information, one AOA/PDOA receiver and one PDOA are used in an outdoor scenario in the 900 MHz band. DWG1, EWG-LT
TD(18)07016 Antenna Aperture Impact on Channel Delay Spread in an Urban Outdoor Scenario at 17 and 60 GHz Cheikh Diakhate, Jean-Marc Conrat, Jean-Christophe Cousin, Alain Sibille The substantial amount of frequency bandwidth available in the spectrum bands above 6 GHz has made millimeter–Wave technology a preferred candidate in the achievement of very high data rates for future generation (5G) communication systems. In this paper, large scale radio propagation parameters such as channel delay spread (DS) are investigated at 17 and 60 GHz in an urban outdoor environment. Measurements are conducted using a wideband channel sounder and azimuth–delay power profiles (ADPPs) and channel DS metrics are processed. The propagation channel characteristics at 17 and 60 GHz are compared through the computed ADPPs and antenna aperture impact on channel DS is mainly discussed. DWG1
TD(18)07017 Predicting Wireless Coverage Maps Using Radial Basis Network Yisroel Mirsky, Yoram Haddad, Orit Rozenblit, Rina Azoulay Accurate assessment of the wireless coverage of a station is a critical step toward deploying more base stations in Ultra Dense Networks, and it is considered as one of the key features of the 5G networks. Quickly and efficiently determining the reception coverage of transmitters becomes a complicated problem when interfering transmitters are introduced to the scenario. It becomes increasingly more complicated when the transmission powers of those transmitters are not uniform. Artificial Neural Networks are the most suitable learning algorithms for recognizing and predicting different sorts of patterns. In particular, a Radial Basis Network is a type of Artificial Neural Network which typically uses a Gaussian kernel as an activator as opposed to a sigmoid function. In this paper, we suggest using Radial Basis networks in order to predict coverage maps. We show how it is possible to train the Radial Basis Network to generate coverage maps based on samples and we check the accuracy level of the learning process on a test set. Using Radial Basis Network can improve the cellular coverage prediction and therefore it can enable a more efficient spectrum allocation. DWG3
TD(18)07018 Wireless Controller Placement Problem Amit Dvir, Yoram Haddad, Aviram Zilberman Software Defined Networking decouples the control and data planes. The response time and quality of service of the controllers is a key aspect in implementing the Software Defined Networking paradigm. A wireless Software Defined Networking control plane is even more challenging. Many radio communication problems arise in modeling the wireless east west bound and southbound interfaces. Wireless networks feature many unique components and metrics that often do not exist in wired networks: separate control transport may intensify on the latency within the wireless data plain with additional interference. Obviously, Wi-Fi based control plane has its implications, e.g., higher packet loss and hidden or exposed terminals. Moreover, wireless links can be operated in a number of different wireless characteristics, e.g., transmission rates and power settings. In this paper we define and solve the known Controllers Placement Problem, but for a Wi-Fi based control plane: the Wireless Control Placement Problem.We define the metrics for an effective wireless controllers placement and propose a multi-objective optimization for the Wireless Controller Placement Problem. Then we evaluate the influence of the variant metrics on the number of controllers and their locations. DWG3
TD(18)07019 Implementation of Low-complexity Hybrid Analogue-digital Solutions in CAP-MIMO Rooderson Martines de Andrade, Fernando J. Velez, Kun Chen, and Ana Garcia Armada The main goal of this joint activity is to explore a simplified version of massive MIMO (mMIMO) with few Universal Software Radio Peripherals (USRPs), where each of them can implement a 2×2 MIMO. By synchronizing them and with appropriate signal processing techniques and algorithms we propose to have a low complexity version of mMIMO, while implementing the hybrid analogue-digital solutions we are proposing in hardware and software within our research. In the Short Term Scientific Mission (STSM) performed by Rooderson Andrade, from Instituto de Telecomunicações/UBI. in Universidade Carlos III de Madrid (UC3M), in April 2018, the aim has been to familiarize with the USRPs that configure the UC3M MIMO testbed, with the longer-term goal to conduct joint experimental research on massive MIMO and hybrid analogue-digital precoding schemes. During the STSM, USRPs have been synchronized, starting from a SISO communications system, by considering 16 Quadrature Amplitude Modulation (QAM). The implementation of the reception code is based on interpreting the signal sent by the transmitter, in a certain time, upon receiving the data in wireless communication, by means of either antennas connected to the USRP or by means of a cable connection. Synchronization only occurs when the same modulation frequency is obtained at both transmitter and receiver. Through experimentation and the application of an enhanced synchronization algorithm, the software from the receiver is being tuned up. This is the appropriate intermedium step to grow to a low complexity version of massive MIMO. DWG1, DWG3, EWG-RA
TD(18)07020 Insights on Spectrum Sharing in Heterogeneous Networks with Small Cells Bruno C. Silva, Sofia C. Sousa, Emanuel Teixeira, Fernando J. Velez This work explores the viability of 5G New Radio spectrum sharing in Ultra High Frequency (UHF), Super High Frequency (SHF) and millimetre wavebands(mmWaves) in outdoor environments. In the mmWaves the linear cellular topology is considered while in the UHF/SHF bands cells with hexagonal shape are assumed. Performance evaluation includes the study of the behaviour of PHY and supported throughput for 2.6, 3.5, 28, 38, 60 and 73 GHz. While the two-slope model is considered for the 2.6 and 3.5 GHz frequency bands, the modified Friis propagation model, with shadow fading, and different values for the standard deviation, is the considered in the millimetre wavebands. With sharing, lower system capacity is supported. We clearly observe that, for coverage distances up to circa 100 m, the supported throughput is higher at the millimetre wavebands, mainly due to the reduction that characterizes the application of the two-slope propagation model at the UHF/SHF bands. DWG3
TD(18)07021 FM Band Channel Modelling and Measurements Omar Ahmadin and Mehmet Kemal Ozdemir As the demand for higher data rates is increasing every day, the the need for new frequency bands becomes more and more prominent. One of the poorly utilized wireless bands is the FM Band between 88 and 108 MHz. The band is being allocated only for relatively highquality audio broadcast around the world. This band has good propagation characteristics and therefore its coverage range and its penetration through buildings are excellent. As FM coverage is so ubiquitous around the world, several applications can be considered to better exploit this useful band. Thus, it is of significant interest to investigate and characterize channel properties of the FM Band for the potential wireless systems. In this paper, we present the results of field measurements at 86 MHz conducted at Gebze, Kocaeli, Turkey. Through the measurements, some of the FM channel characteristics are identified. The measurement environment was rich and of different scenarios that included: line-of-sight, non-line-of-sight, urban, badurban and rural areas. Our results show that the FM channel posses large channel excess delay and hence for the use of OFDM, long cyclic prefix is required. Moreover, as 5G systems aim to utilize lower frequency bands for supplementary links, FM Band can be considered as one of the potential bands. DWG1
TD(18)07022 A Study of Polarimetric Diffuse Scattering at 28 GHz in an Urban Open Square Pasi Koivumäki, Sinh L. H. Nguyen, Katsuyuki Haneda, Gerhard Steinböck This paper studies suitability of two polarimetric diffuse scattering models of electromagnetic fields from a highly inhomogeneous modern building wall at 28 GHz in the context of ray-based wave propagation simulations. Parameter values of the scattering models are estimated in reference to polarimetric channel sounding at the same site. We found that the single-lobe directive model of scattering is not suitable for the studied wall because backscattering is dominant. Instead, the Lambertian model for scattering is found to reproduce the measured reality well. The parameter values giving the best fit of the scattering model to measurements are on the same arange as those found in literature for below-6GHz frequnecies. DWG1
TD(18)07023 Measured Channel Hardening in an Indoor Multiband Scenario Golsa Ghiaasi, Jens Abraham, Egil Eide and Torbjörn Ekman A study of channel hardening in a large-scale antenna system has been carried out by means of indoor channel measurements over four frequency bands (1.472 GHz, 2.6 GHz, 3.82 GHz and 4.16 GHz).
NTNU’s Reconfigurable Radio Network Platform has been used to record the channel estimates for 40 single user non-line of sight radio links to a 64 element wide-band antenna array.
By examining the root mean square delay spread and the ratio of the normalized subcarrier to average single input single output link power of the radio channel received by a single user after combination, the hardening of this equivalent channel is analyzed for various numbers of nodes.
The channel hardening merits show consistent behaviour throughout the frequency bands.
By combining 16 antennas the delay spread of the equivalent channel is reduced from more than 100 ns to less than 35 ns with significantly reduced variation in the channel power.
DWG1
TD(18)07024 UWB RSS-based Localization for Capsule Endoscopy using a Multilayer Phantom and In-Vivo Measurements Martina Barbi, Concepcion Garcia-Pardo, Andrea Nevarez, Vicente Pons, Narcís Cardona In recent years, localization for capsule endoscopy applications using Ultra-Wideband (UWB) technology has become an attractive field of investigation due to its potential benefits for patients. Literature concerning performance analysis of RF-based localization techniques for in-body applications at UWB frequencies is very limited. Available studies mainly rely on Finite Difference Time Domain (FDTD) simulations, using digital human models and on experimental measurements by means of homogeneous phantoms. Nevertheless, no realistic analysis based on multilayer phantom measurements or through in-vivo experiment has been reported yet. This paper investigates the performance of RSS-based approach for two-dimensional (2D) and three-dimensional localization (3D) in the UWB frequency band. For 2D localization, experimental laboratory measurements using a two-layer phantom based setup have been conducted. For 3D localization, data from a recently conducted in-vivo experiment have been used. Localization accuracy using path loss (PL) models, under ideal and not ideal channel estimation assumptions, are compared. Results show that under not ideal channel assumption the relative localization error slightly increases for the 2D case but not for the in-vivo 3D case. Impact of receivers selection on the localization accuracy has also been investigated for both, 2D and 3D, cases. EWG-LT,SEWG-IoT
TD(18)07025 Hierarchical Decoding with Bit-Wise Soft-Aided H-SODEM and Iterative Double-Loop Processing Jan Sykora This paper addresses Wireless Physical Layer Network (WPNC) coding using Isomorphic Layered Network Coded Modulation (NCM) in hierarchical MAC stage with Hierarchical Decode and Forward (HDF) strategy. We focus on using binary component codes in bit-wise mapped higher-order hierarchical constellations. This creates a complicated nonlinear block-like inter-bit structure binding and the bit-wise observation model cannot be any longer described by single-letter entities. The nonlinear inter-bit structural binding strongly depends on the source constellation bit mapping, actual bit-wise a priori PMFs, and also on the actual relative channel parametrization. We derive bit-wise soft-aided Hierarchical Soft-Output Demodulator (H-SODEM) and analyze the bit error rate properties of the dual-loop soft-aided bit-wise hierarchical decoding in 2-source H-MAC HDF scenario. This scheme is shown to significantly improve the performance w.r.t. classical uniform a priori case. DWG2
TD(18)07026 Initial UWB In-Body Channel Characterization Using a Novel Multilayer Phantom Measurement Setup Sofia Perez-Simbor, Martina Barbi, Concepcion Garcia-Pardo, Sergio Castelló-Palacios, Narcís Cardona Wireless Body Area Networks (WBANs) are a promising technology for medical purposes. Currently the WBAN are classified into: implanted (in-), surface (on-) or outside (off-) body communications regarding the location of the devices with reference to the human body. The Ultra Wide-Band (UWB) frequency band is growing as a band of interest for implanted communications because of its high data rate and low power consumption among other benefits. Software simulations, in-vivo measurements and experimental phantom measurements are common methods to properly characterize the propagation channel. Nevertheless, up to now, experimental phantoms measurements presented in the literature show some inconveniences, i.e., the accuracy of the phantoms compared with the real human tissues or the testbed used for the measurements. This paper aims at overcoming these issues using accurate phantoms designed for the purpose of implanted communications in the UWB frequency band. In addition, a multilayer phantom container was developed. This container has capacity for two different phantoms, emulating a heterogeneous propagation medium for in-body measurements. Moreover, a novel setup was built for in-body phantom measurements. As a result, an experimental path loss model is presented from the measurements obtained with phantoms. Besides, software simulations mimicking the experimental setup are performed in order to validate the previous results obtained SEWG-IoT
TD(18)07027 Spatial Statistical Analysis for the Design of Indoor Particle Filter based Localization Mechanisms Miguel Martínez del Horno, Ismael García Varea and Luis Orozco Barbosa The deployment of accurate and robust wireless indoor localization mechanism should enable the implementation of a wide variety of contextbased applications. From health services to leisure activities, location-awareness will ease the service delivery process and enhance the user quality of experience. However, the development of accurate and robust wireless indoor mechanisms face major challenges due to the random and unpredictable nature of radio channels. In this paper, we show that the information to be used in the development of particle-filter-based indoor localization mechanisms will greatly benefit from other sources of information. EWG-LT
TD(18)07028 Experimental Demonstration of BLE Transmitter Positioning based on AOA Estimation Shaghayegh Monfared, Trung-Hien Nguyen, Luca Petrillo, Philippe De Doncker, Francois Horlin The introduction of the Bluetooth Low Energy (BLE) standard significantly streamlines the development of the Internet of Things (IoT) applications. These applications often require the sensor positioning to link the measurements with its location. Therefore, it is essential to conduct studies on BLE-based positioning methods. Fingerprinting-based positioning approaches are commonly used in BLE network. However, these methods have their own limitations in terms of practical use and ease of implementation. The purpose is to develop a simple BLE-based positioning of high accuracy. In this paper, a BLE-based positioning method is proposed based on Angle of Arrival (AOA) estimation. Multiple Signal Classification (MUSIC) algorithm is used for angle estimation due to the high angular resolution and sensitivity. Several experiments have been conducted in an indoor environment and compared with simulation results. Experimental results show that our proposed BLE-based positioning method achieves a promising average positioning accuracy of 11 to 15 centimeters. EWG-LT
TD(18)07029 Characterizing and Modeling the Wideband Vehicle to Pedestrian Propagation Channels Gloria Makhoul, Raffaele D’Errico, Claude Oestges This paper presents a vehicle to pedestrian (V2P) channel model based on an extensive measurement campaign. Several propagation conditions and different mobility patterns were investigated. The parameters for a geometry-based stochastic channel modeling (GSCM) are given. For the strongest path and secondary discrete components the path loss (PL), large and small scale fadings are presented. DWG1
TD(18)07030 Network Design for Accurate Vehicle Localization José A. del Peral-Rosado, Gonzalo Seco-Granados, Sunwoo Kim, and José A. López-Salcedo Connected autonomous driving demands unprecedented precise, reliable and secure positioning, with localization requirements below one meter. This stringent demand is pushing for the use of sensors that fully exploit the positioning capabilities of current and future fifth generation (5G) wireless networks. However, these networks are not typically designed for positioning but for data communication purposes, which follow a different paradigm for the network deployment and operation. This paper provides practical guidelines on the network design with the aim of achieving accurate vehicle localization in road scenarios. To do so, the Cramér-Rao bound (CRB) for joint time-of-arrival (ToA) and angle-of-arrival (AoA) localization is used to improve the site placement along the roads. In addition, the achievable positioning accuracy of conventional and improved vehicle-to-infrastructure (V2I) deployments is assessed. The simulation results indicate the need to locate the network sites at both sides of the road, and to use antenna arrays in these sites in order to ensure a vehicle location accuracy below one meter on the 95% of the cases. EWG-LT
TD(18)07031 Resource Allocation and Sharing for Heterogeneous Data Collection over Conventional 3GPP LTE and Emerging NB-IoT Technologies Samouylov K. and Gaydamaka Y. In this work we present one of the approaches to the analytical modeling of next-generation mobile networks, which offer sufficient levels of flexibility to dynamically share the radio resources among the competing data streams with dissimilar performance requirements. However, improved flexibility calls for novel methods to analyze the system performance as heterogeneous traffic sessions are being served. The focus of attention in this work is the IoT traffic, more precisely, the problem of the radio resources sharing between conventional LTE and NB-IoT technologies. The combination of two or more heterogeneous big data streams is one of the key features in 5G mobile networks, which increases the intelligence and reliability of decision-making and, consequently, unleashes the full potential of the IoT. This need has been recently recognized by 3GPP with the ratification of a dedicated inband deployment mode in LTE Rel. 13. Today, this combination receives significant support from industry and is predicted to become one of the de-facto solutions for heterogeneous big data collection in various IoT applications. However, even by offering the needed flexibility in how radio resources may be shared between LTE and NB-IoT technologies, 3GPP does not provide specific guidelines on how these resources should be shared. In this work, we target to resolve the above challenges by contributing an analytical framework for performance modeling of heterogeneous data collection over a 5G mobile network. Using the developed modeling tool, we characterize and compare three feasible strategies for resource allocation and sharing between LTE and NB-IoT sub-systems, namely, static, dynamic, and dynamic with reservations. As a result of our study, we advocate for the third strategy as the most appropriate in the heterogeneous traffic scenarios as well as demonstrate how to best parametrize it for particular IoT traffic patterns. DWG3
TD(18)07032 On Simple Scattering and Diffraction Models using Point Cloud Maps for Channel Model or Coverage Predictions Jean-Frederic Wagen and Karol Kruzelecki One of the several challenges for high capacity wireless communications is to find a suitable propagation model able to predict as accurately as possible the propagation channel to assess the performance of wide-band wireless systems. The propagation channel is here described by its impulse response, i.e., a set of multipath components due to radio propagation. An investigation of so-called point cloud propagation models based on the detailed topographical data available in Switzerland is conducted. The results of the point cloud predictions are compared to wide band impulse response measurements. To challenge the validity of the prediction models, simulation results have been compared to 5 GHz WiFi connectivity measurements for an outdoor picocell. The results are encouraging: point cloud map based models might prove to be useful to provide realistic radio channels or coverage prediction. DWG1
TD(18)07033 TAKE – Tactical Ad-Hoc Network Emulation Simon Ruffieux, Christophe Gisler, Jean-Frederic Wagen, Francois Buntschu and Gerome Bovet This contribution presents our current work in the area of Mobile Ad-Hoc Networks (MANETs) which might be of interest to those involved in V2V communications, especially the emulation of such networks. The uses of tactical radios to communicate in case of emergency and rescue situation is a typical real use case of MANETs. Due to the operating environment, these radios experience specific characteristics such as limited bandwidth, in addition to high delay and packet losses. This contribution presents the work achieved to develop, evaluate and test a novel application-layer routing algorithm specifically designed for tactical MANET networks. In order to evaluate the proposed algorithm in real conditions, two platforms and specific Quality of Experience metrics have been developed. DWG3
TD(18)07034 An SLA-Based Method for Radio Resource Slicing and Allocation in Virtual RANs Behnam Rouzbehani, Luis M. Correia, Luísa Caeiro This paper presents a flexible model for Radio Access Network (RAN) slicing, which can be considered as a step towards realising the so-called RAN-as-a-Service concept. The key objectives are to define a level of performance isolation in between the Virtual Network Operators (VNOs), which are acting as network tenants, in order to ensure that their contracted Service Level Agreements (SLAs) will not be affected by variation of different network parameters, while at the same time, to optimise the usage of RAN infrastructure by dynamic radio resource sharing among various slices, and in a fair manner. To achieve these goals a centralised virtualisation platform called VRRM is modelled as an individual management entity, which does not own the infrastructure and is in charge of satisfying the demands of different service slices based on the aggregated capacity provided by multiple Radio Access Technologies, owned by Infrastructure Provider. In order to evaluate the model a practical scenario with 3 VNOs and differentiated types of contracted SLAs is proposed to provide a range of customised services. Results under variation of different network parameters, including traffic load, SLA and serving weights confirm a level of performance isolation between the VNOs, while potentially 100% of the aggregated capacity can be utilised on demand to satisfy different service requirements to the highest achievable level, according to the context of proportional fairness. DWG3
TD(18)07035 Spatial Data Focusing: an alternative to Beamforming for geocasting scenarios Julien Sarrazin, Michael Odhiambo, Sidney Golstein, François Horlin, Philippe De Doncker An alternative scenario is introduced in order to overcome antenna array’s beamwidth limitations due to finite aperture size. The proposed approach aims to focus the transmitted data rather than the transmitted power. This scheme enables wireless broadcast of information to specific spatial locations, using fewer antenna elements compared to classical beamforming techniques. It is shown indeed with numerical examples that focusing the data is spatially more selective than focusing the power. In particular, we show that a linear 2-antenna array using spatial data focusing can exhibit similar beamwidths to a linear 7-antenna array using power focusing. DWG1
TD(18)07036 Extended TDL Modeling for V2X Channels Nina Hassan, Martin Kaske, Gerd Sommerkorn, Christian Schneider and Reiner Thomä The topic of this paper is focused on tapped delay line (TDL) channel modeling for vehicle to X (V2X) applications. TDL model parameters have been derived using measurements. The classical TDL model is extended using a Markov chain to implement non-WSSUS. A new approach is proposed to derive these parameters and first results will be discussed. DWG1
TD(18)07037 Simultaneous Multi-band Indoor Measurements from 6 to 60 GHz – a Study on System Influence on Channel Modelling Diego Dupleich, Robert Müller, Sergii Skoblikov, Christian Schneider, Jian Luo, Giovanni Del Galdo, and Reiner Thomä In the present paper we introduce simultaneous multi-band ultra wideband directional measurements at 6.75 GHz, 30 GHz, and 60 GHz in an indoor environment with different visibility conditions. Large scale parameters and pathloss has been analysed for the different bands considering the propagation channel, and later the influence of the system aspects in the radio channel.We have observed that the major differences between bands are introduced by the characteristics of the targeted system. DWG1
TD(18)07038 V2V/V2R Channel Measurements on a Highway at 2.53GHz:
A Delay and Doppler Discussion
Gerd Sommerkorn, Daniel Czaniera, Martin Käske, Christian Schneider and Reiner Thomä The time variant characteristic of the vehicle to X (V2X) channel is discussed using channel sounding measurements. For selected use cases and situations spectrograms in the time-delay as well as the Doppler domain are shown based on sequences of the local scattering function (LSF). Dominant fixed and moving scatterers are identified by visual inspection using proper meta data. DWG1
TD(18)07039 The hypervisor-based and container-based virtualization in IoT environment Borislav Djordjević, Valentina Timcenko Internet of Things concept relies on the application of a range of different devices with specific interfaces, communication practices, and variable amounts of data exchange. Therefore, IoT requires stable, secure and reliable network environment. IoT environment highly depends on available computing power and storage space, thus and adequate infrastructure should be wisely designed, considering all the challenges for efficient functioning. The rise of the virtualization techniques has indicated their application in IoT infrastructures. We have evaluated the performances of the hypervisor-based and container-based virtualization techniques which are strongly compatible to IoT environment. The focus is on a comparison of performance of hypervisor-based virtualization, taking the Linux KVM as a representative, and container-based virtualization represented by Docker, whereas the file system performance are taken as a basis for performance comparison analysis. Testing procedures are carried out with Filebench application, providing for both virtualization environments the equivalent conditions, test methods and independence from the impact of hardware or other system component. The performances are compared for KVM hipervizor as the native host with one, two and three virtual machines, while Docker is analyzed considering structures with one, two and three containers. We have analysed the expected behaviours, verified the assumptions with Filebench test software, and provided the concluding remarks. EWG-IoT
TD(18)07040 Millimeter wave channel measurements in an intra-wagon environment Vicent M. Rodrigo-Peñarrocha, Lorenzo Rubio, Juan Reig, Leandro Juan-Llácer, Juan Pascual-García and José María Molina-García-Pardo In this contribution we present results of the propagation channel characteristics in an intra-wagon environment in millimeter wave frequencies. The measurements were collected inside an underground convoy from 25 to 40 GHz in the frequency domain using as a novelty a radio over fiber (RoF) link in order to avoid the high losses introduced by cables at these frequencies and allowing long distances between the transmitter and receiver antennas. Path loss, delay spread and coherence bandwidth values are reported at the potential millimeter wave (mmWave) bands to deploy the future 5G systems. These results allow us to have a better knowledge of the propagation channel characteristics in this particular environment, characterized by rich-scattering with long delays. DWG1
TD(18)07041 Information transfer from FRET-based nanonetworks to nerve cells Jakub Kmiecik, Pawel Kulakowski, Krzysztof Wojcik, Andrzej Jajszczyk In this short paper, it is discussed how signals from FRET-based nanonetworks can be received in nerve cells, i.e. neurons. In this sense, a new interface allowing for communication between nanonetworks and human neural system (much larger in scale) is proposed. The paper is focused on two system components: fluorophores and channelrhodopsins which serve as transmitters and receivers, respectively. Channelrhodopsins are used here to convert FRET signals to electrical voltage which can propagate, as action potentials, through neurons on long distances. The trade-off between transmission rate and bit error rate is also investigated. SEWG-IoT
TD(18)07042 Elaboration of Simple Gel Phantoms for 5G/mmWave Communications Sergio Castelló-Palacios, Reza Aminzadeh, Concepcion Garcia-Pardo, Günter Vermeeren, Narcís Cardona, Wout Joseph, Ana Vallés-Lluch Tissue-mimicking phantoms are widely used in literature for testing devices on emulating scenarios. Current studies are focused on achieving wideband phantoms for technologies covering wide bandwithds. Many of these phantoms have been reported for frequencies which are currently in use for mobile communications services, but not for upcoming 5G systems. Thus, this work aims at developing new phantoms with a working frequency band within 30 and 67 GHz because of their interest in this new communication system. Taking into account that the penetration depth of the body tissues is really low, the skin was the target tissue. Two issues were addressed, the meeting of the dielectric target values with new compounds and the gelling of these mixtures to get firm materials. For this purpose, different simple alcohols were analyzed as candidates for mimicking the skin. Furthermore, it is intended to model these data with different mixing rules in order to estimate the final relative permittivity of the solutions. Additionally, the solutions were gelled with k-carrageenan, which has promising mechanical properties without altering the dielectric ones. DWG1, SEWG-IoT
TD(18)07043 Hybrid virtual polarimetric Massive MIMO measurements at 1.35 GHz F. Challita, P. Laly, M.Liénard, D.P. Gaillot Massive MIMO technology has emerged as one promising technology that will play a key part in the future 5G networks. The massive polarimetric line-of-sight (LOS) channel of an indoor scenario is investigated at 1.3 GHz using a real-time channel sounder. The massive MIMO transmitter is constructed using a hybrid architecture including a vertical uniform linear array (V-ULA) at different positions forming a virtual, yet realistic uniform rectangular array including mutual coupling effects. The performance of the system is evaluated for different polarization schemes and different receiver orientations using propagation channel based metrics (such as receiver spatial correlation) and system oriented metrics such as sum-rate capacity and signal to interference and noise ratio. The results show notable performance differences depending on the polarization schemes and receiver orientation paving the way for further capacity enhancements in massive MIMO systems. DWG1
TD(18)07044 Specification of the Internet of Things platform for energy efficient living Lazar Berbakov, Nikola Tomašević, Marko Batić Recent advances in wireless networking and microelectronic fabrication have enabled a mass production of low-cost computationally capable miniature devices that can be used in different innovative solutions. Since residential sector has been identified as one the most energy demanding, there exists a strong interest in exploitation of connected smart devices with the aim of improving energy efficiency, user comfort and the overall quality of life. The IoT platforms that will be developed within the RESPOND and InBetween projects aim to reach the aforementioned goals with the combination of smart monitoring and control devices with the advanced energy services capable of analysing the collected data and providing control actions and suggestions towards the end users via intuitive mobile and web applications. The aim of this document is to provide preliminary specification for two platforms and related systems that will be developed during the course of the RESPOND and InBetween projects. EWG-IoT
TD(18)07045 Correlation-based Clustering Procedure Towards Energy-Efficient Cooperative Spectrum Sensing Krzysztof Cichoń, Adrian Kliks, Hanna Bogucka The article presents an analysis of correlationbased clustering procedure in cooperative spectrum sensing. The motivation is to assess if it is more beneficial in terms of energy efficiency to group nodes according to the received signal-to-noise ratio (SNR) on the link between Primary User and node or according to the distance between nodes. To this end, a merged clustering measure is introduced. Then a number of network topologies are compared via computer simulations. Moreover, the temporal analysis to the correlation-based procedure is introduced. DWG2
TD(18)07046 Modelling Polarimetric Power Delay Spectrum for Indoor Wireless Channels via Propagation Graph Formalism Ramoni Adeogun and Troels Pedersen This paper presents approximate expressions for polarimetric power delay spectrum and cross-polar power ratio via propagation graph modelling formalism. The expressions are derived considering average signal propagation in a graph. The models relate co- and cross-polar power and the power ratio to model parameters (number of scatterers, probability of visibility, reflection gain and polarization coupling parameter) thereby providing a useful approach to investigate the averaged effect of these parameters on the channel statistics. Simulation results show statistics obtained using the model and the approximate expressions match very closely DWG1
TD(18)07047 On Clustering in Multipath Channel Models Alister Burr, Katsuyuki Haneda and Aki Karttunen Clustering is now nearly ubiquitous concept in stochastic multipath channel modelling, based on observation in channel measurements of groups of multipath components in the delay-angular domain. However it is possible for such groups to occur by chance even when they result from an underlying uniform Poisson point process. This paper therefore proposes a statistical analysis technique to determine whether a given distribution of components is likely to have arisen from such a uniform distribution, or whether there is evidence of an underlying clustered process. The approach can also be applied if the density of the Poisson process is not uniform. The approach is applied to a set of indoor measurements taken at 63 GHz, as an example. The technique provides evidence, even taking into account the non-uniformity of the component density, that clustering is present in these measurements beyond what might be expected by chance. DWG1
TD(18)07048 Conformal Automotive Roof-Top Antenna Cavity With Increased Coverage to Vulnerable Road Users Gerald Artner, Wim Kotterman, Giovanni Del Galdo and Matthias A. Hein Cooperatively driving cars benefit from increased coverage towards driving direction for communication with vulnerable road users. Antenna cavities were designed, prototyped and measured for integration into car roofs above the windshield. Two different antenna cavities were investigated. First, an antenna cavity made from carbon fiber reinforced polymer was measured without a vehicle, to obtain general results without model specific influence. Second, a metal cavity was built into the roof of a sedan type passenger car to include the marked effects of the car body and provide a proof of performance. Gain patterns were measured in anechoic chambers. Results show that the antenna structure and mounting position are suitable for omnidirectional radiation with increased radiation towards low elevation angles in driving direction. DWG2, EWG-OTA, EWG-IoT
TD(18)07049 Fixed link long term measurements Sana Salous, Yusheng Cao, Xavier Raimundo The TD gives an overview of the experimental set up to study the impact of precipitation on fixed links in the 28 GHz and 70 GHz bands. Preliminary results of dual polarised measurements are presented with disdrometer data which give several parameters including rain-fall rate and drop size distribution. The measurements are compared with two models based on the rain data parameters. DWG1
TD(18)07050 Modeling Human Blockage at 5G Millimeter Wave Frequencies Usman Tahir Virk and Katsuyuki Haneda Millimeter wave (mm-Wave) spectrum unravels the humongous and accelerating demand for wireless data rates and, therefore, it will be a fundamental ingredient of the fifth-generation (5G) wireless technology. In case of mm-wave access links, humans are the most noticeable blockers of electromagnetic waves from access points to mobile stations and hence cause temporal variation in the radio channel. This paper: (1) presents a thorough literature survey of existing human blockage models and their quantitative comparison, (2) characterizes human blockage through anechoic chamber measurements at 15, 28 and 60 GHz frequencies employing 15 human subjects of different sizes, and finally (3) introduces an efficient three-dimensional (3D) physical human blockage model based on simple geometrical description of human body. The blockage loss increases with the increase in frequency and is on average 7-10 dB more at 60 GHz than at 15 GHz. It is observed that body width and height are the key parameters which affect the human blockage significantly. The oblique orientation of human body results in relatively more blockage loss compared to the positions where the frontal plane of the human body is either parallel or perpendicular to the direct-wave path. Furthermore, the blockage loss decreases as the height of transmitter (Tx) increases. The proposed blockage model correlates substantially with the measured results. DWG1
TD(18)07051  Next steps in channel modelling and OTA test methods for 5G Moray Rumney 3GPP have made decisions on provisional OTA test methods for 5G NR at frequency range 2 (24.25 GHz – 52.6 GHz) for RF and non-spatial throughput testing as well as a basic two signal setup for radio resource management. This paper will review current decisions and outline the open issues for channel modeling and development of spatial test methods for static and dynamic fields. EWG-OTA
TD(18)07052 Performance Evaluation of Source Routing Minimum Cost Forwarding Protocol over 6TiSCH applied to the OpenMote-B platform Fernando José da Silva Velez; Gordana Gardašević; Anderson Rocha Ramos The aim of this work is the development of 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). To perform this evaluation, 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. Another goal of this project is to give contribution to the investigation of the applicability of quality of service 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. This contribution is a continuation of a previous work done during a short-term scientific mission where researchers from University of Beira Interior and University of Banja Luka developed the SRMCF protocols using simulations and the Contiki operating system. Once the programming code is implemented, the team will investigate the possibilities to apply quality of service over the stack developed. Next, the team will also investigate the possibilities to explore long range routing techniques using the OpenMote platforms. In this task, we will use xBee, LoraWAN, Raspberry PI and Arduino platforms. EWG-IoT
TD(18)07053 Use of Digital Maps in Context of Radio Propagation Simulations Marjo Heikkilä, Aki Hekkala, Ossi Saukko This paper introduces the use of digital maps for use of demanding air interface evaluations in 5G and beyond communication systems. The digital map contains the information of the environment and uses a deterministic calculation method to search for, e.g., the propagation links. The problem faced most often by the simulation expert is that there is no digital map containing the necessary information in a usable format, or the information is spread over multiple sources. Importing functionalities are, therefore, required. Ideally, the target is to have a single user interface where the information is combined and all the editing functions are performed for the simulation or possibly for the emulation run and, finally, the results are looped back to the map created. This approach does not exclude any hybrid simulation method to be used like a combination of ray–tracing and GSCM modelling. DWG1
TD(18)07054 Measurement based ultra-wideband channel model for mobile communications in tunnels Andrej Hrovat, Klemen Bregar, Tomaž Javornik In this document, we provide the results of broadband channel measurements in an old railway tunnel at two carrier frequencies, namely 4 and 6 GHz, and two channel bandwidths: 500 MHz and 1 GHz. The UWB signal at carrier frequency of 4 GHz exhibits higher path loss compared to the 6 GHz signal in observed tunnel environment while the signal with 1 GHz bandwidth shows lower path loss compared to the 500 MHz signal. The delay spread is increasing with distance between transmitter and receiver; however, at the transmitter proximity a decrease of the rms delay spread is observed resulting in the rms delay spread minimum at 10 to 15 m from the transmitter. The three slope channel model for broadband UWB radio channels comprising of path loss and rms delay spread functions, is also proposed applying measured signal strength and channel impulse response values. DWG1
TD(18)07055 Localization of Scatterers in Railway Environments for Train-to-Train Propagation Paul Unterhuber, Michael Walter, Thomas Kürner Wireless communication became a key technology in the transportation domain. An increase of efficiency and safety can be achieved by connecting all traffic participants. In the railway domain wireless communication could enable new applications. In this contribution we focus on train-totrain (T2T) communication and investigate the propagation conditions. In typical railway environments different types of objects along the track highly influence the propagation channel and, in turn, the performance of wireless T2T communications. Therefore, the characterization and modeling of the propagation effects are indispensable. In comparison to cellular or vehicle-tovehicle communication, T2T propagation is hardly investigated. In this paper we present how key parameters of the multipath components (MPCs) of the channel impulse response can be estimated. The estimation is based on measurement data. We estimate delay and Doppler of single-bounce MPCs and estimate the location of the corresponding scatterers. DWG1
TD(18)07056 Spatial consistency of clusters in mm-wave ray-tracing results for 5G communications Manijeh Bashar, Katsuyuki Haneda and Alister Burr The available geometry-based stochastic channel models (GSCMs) at millimetre-wave (mmWave) frequencies do not necessarily retain spatial consistency for simulated channels, which is essential for small cells with ultra-dense users. In this paper, we work on cluster parameterization for the COST 2100 channel model using mobile channel simulations at 61 GHz in Helsinki Airport. The paper considers a ray-tracer which has been optimized to match measurements, to obtain double-directional channels at mmWave frequencies. A joint clustering-tracking framework is used to determine cluster parameters to be used in the COST 2100 channel model. The KPowerMeans algorithm and the Kalman filter are exploited to identify the cluster positions and to predict and track cluster positions respectively. DWG1
TD(18)07057 Relative Positioning and Velocity Component Estimation of Two Vehicles by using the Time-VAriant, Delay-Dependent Doppler Spectrum M. Walter The estimation of the velocity of transmitter and receiver is important in several wireless applications, like resource management, adaptive modulation and coding, channel assignment, channel estimation, and localization. The presented approach takes into account the information of the instantaneous Doppler power spectrum close to the line-of-sight and far away from it. Since the corner frequencies are dependent on the relative movement and position, i.e., the geometry, between the vehicles, the velocity components relative to the line-of-sight can be deduced. With this knowledge the angle between the velocity vector of the vehicle and the semi-major axis of the distance ellipsoid can be determined. If the line-of-sight is available, the relative positioning is done by angle and distance, similar to estimating the bearing and distance to a lighthouse in marine navigation or DME (distance measuring equipment) and VOR (VHF omnidirectional radio range) in aeronautical navigation. DWG1
TD(18)07058 Window loss measurements and Model Validation Satyam Dwivedi, Jonas Medbo In this paper we present our recent work on window loss measurements. The work involves measurement campaign and analyzing the measurements. The measurements are compared with the window loss model published in ITU P.2040. The measurements validate the models with very good precision. DWG1
TD(18)07059 Exchanging Transmitter Maps in Multipath Assisted Positioning Markus Ulmschneider, David Calvo Luz, Christian Gentner While multipath propagation has commonly been regarded as a drawback for wireless localization technologies, the spatial information contained in multipath components (MPCs) can be exploited for positioning a user. In multipath assisted positioning, each MPC arriving at a receiver is regarded as a line-of-sight signal from a virtual transmitter. We assume the locations of the physical and virtual transmitters to be unknown and estimate them jointly with the user position with simultaneous localization and mapping (SLAM). In a setting where multiple users move in the same scenario, maps of physical and virtual transmitters can be exchanged among them. However, these maps are in different local coordinate systems with unknown relative rotation and translation. The distances among transmitters within each map are exploited in order to find correspondences among transmitters in different maps. Based on the correspondences, the unknown rotation and translation parameters are estimated. This allows a user to exploit the information in a transmitter map received from other users, and hence extends our multipath assisted positioning approach from a single user to a cooperative radiolocation algorithm. In simulations in an indoor scenario we show that using a prior transmitter map decreases the user positioning error although the map is in an unknown coordinate system different from the user’s. EWG-LT
TD(18)07060 Joint Path and Radio Resource Management for UAVs Supporting Mobile Radio Networks Silvia Mignardi, Roberto Verdone In this paper we investigate the potential advantages of using a roaming Unmanned Aerial Vehicle (UAV) as base station of a mobile radio network deployed in a city. The design of the UAV dynamic trajectory and Radio Resource Management (RRM) strategies are combined, with the goal to improve the sum throughput of the network. The comparison between joint and separate aerial-terrestrial RRM is discussed. With respect to previous papers, we identified a cost function, used to define the UAV path, improving significantly the performance. DWG3, EWG-IoT
TD(18)07061 Spatiotemporal Gait Variables using Wavelets for an Objective Analysis of Parkinson Disease Yor Castaño, Juan Arango and Andres Navarro Parkinson’s disease generates a special interest in factors such as gait patterns, posture patterns, and risk of falls. The human gait pattern has a basic unit called the gait cycle, composed of two phases: stance and swing. Using gait analysis it is possible to get spatiotemporal variables as walking speed and step number derived from stance and swing phases. In this paper, we explore the feasibility of wavelet techniques to analyze gait signals, we use a member of Daubechies family to distinguish automatically gait phases, this approach allowed us to estimate spatiotemporal variables that shows significant differences between Parkinson patients and non-Parkinson patients, this result aims to allow clinical experts to easily diagnose and assess Parkinson patients, with short evaluation times and with non-invasive technologies. SEWG-IoT
TD(18)07062 Joint Aerial-Terrestrial Resource Management in UAV-Aided Mobile Radio Networks Roberto Verdone, Silvia Mignardi This article addresses the issue of joint aerial-terrestrial resource management in mobile radio networks supported by an unmanned aerial vehicle (UAV) operating as network node and discusses the potentials of the true integration between the terrestrial and the UAV components of the network. Issues like a suitable network architecture, services of interest and user traffic distribution, the UAV physical layer and radio channel are discussed. In particular, relevance is given to UAV trajectory design and radio resource management (RRM). A simulation campaign shows that, by properly optimizing the system parameters related to the drone flight, a single UAV can bring a significant improvement in terms of network throughput in a wide service area. In particular, the usage of a joint RRM approach, where the UAV and the terrestrial bases operate in a coordinated manner, significant advantages are found with respect to the implementation of RRM algorithms with no coordination. DWG3, EWG-IoT
TD(18)07063 Wideband Channel Measurements for Polarised Indoor Off-Body Communications Kenan Turbic, Slawomir J. Ambroziak, Luis M. Correia, Marko Beko This paper presents the initial results of wideband channel measurements for polarised off-body communication at 5.8 GHz, in an indoor environment. Channel Impulse Response measurements were performed simultaneously for two orthogonal polarisations of the wearable antenna, and repeated for vertical and horizontal orientations of the off-body one. Four types of measurement scenarios were considered in order to investigate the influence of user dynamics, presence of people in the environment, and the body-shadowing effects from the user or another person obstructing the Line-of-Sight in between the transmitter and the receiver. The measurements were performed for several wearable antenna placements, representative of popular Body Area Network applications. In total, approximately 1 GB of measurement data was obtained during the campaign. Only a set of initial results is presented; a detailed analysis, planed for the future, being discussed. DWG1, EWG-IoT
TD(18)07064 A Real-time Computational Resource Management in C-RAN Mojgan Barahman, Luis M. Correia, Lúcio S. Ferreira The concept of bargaining in cooperative game theory is applied in this paper, in order to manage the computational resources of a BBU-pool. The goal is the efficient use of computational resources, while striking an optimum balance amongst all the BBUs in high demand conditions that lead to computational resource leakage. To this end, the BBUs required computational resources are estimated on the basis of a time frame, based on user processing and type of running services. The problem of computational resource allocation is formulated to a bargaining game based on the BBUs instantaneous requirement, the Generalized Nash Bargaining Solution is then applied as a strategy to distribute computational resources in a fair manner. User satisfaction level is evaluated as a performance metric. To this end, a scenario is defined where in, the BBU-pool covers seven cells each generating a different traffic profile. The cells traffic load is generated by a packet level simulation, considering mixture of heterogeneous services. Amount of allocated resources is monitored for all the BBUs in a tidal traffic condition that the results for a 100 ms slice of time is presented. Simulation results confirm that the amount of allocated computational resources is adopted to the BBUs instantaneous demand and according to the priority level of the BBUs running services. Moreover, numerical results show that 100% of the available computational capacity is used in case of need. DWG3
TD(18)07065 A Simple Method for Robust Vehicular Communication with Multiple Nonideal Antennas Keerthi Kumar Nagalapur, Erik G. Stro ̈m, Fredrik Bra ̈nnstro ̈m, Jan Carlsson, and Kristian Karlsson For critical vehicular communication services, such as traffic safety and traffic efficiency, it is advisable to design systems with robustness as the main criteria, possibly at the price of reduced peak performance and efficiency. We describe a simple, low-cost method for combining the output of L nonideal (i.e., nonisotropic) antennas to the input signal to a single- port receiver with the aim to guarantee robustness, i.e., to minimize the probability that K consecutive packets arriving from the worst-case angle-of-arrival are decoded incorrectly. To minimize complexity, the combining network does not estimate or use channel state information (complex channel gains, noise levels, etc.). The combining network consists of L − 1 analog phase shifters whose phases are affine functions of time. For a general L and the case when the packet error probability decays exponentially with the received SNR, the optimum slopes of the affine functions can be computed by solving an optimization problem that depends on the antenna far field functions. We provide an analytical solution for the special case of L = 2 antennas, which turns out to be independent of the antenna patterns. In an experimental setup consisting of two monopole antennas mounted on the roof of a Volvo XC90, the proposed combining method is shown to give significant performance gains compared to using just one of the antennas. EWG-IoT
TD(18)07066 System-Theoretical Modeling and Analysis of Phase Control in a Photonically Steered Terahertz Phased Array Transmitter Kevin Kolpatzeck, Xuan Liu, Lars Häring, Andreas Czylwik The use of photonic phase shift beamforming is highly attractive in terahertz transmitters due to its seamless integration with terahertz generation by photomixing. By feeding several photodiodes with coherent infrared signals with welldefined phase relationships, highly directed and steerable terahertz radiation can be generated. At the same time, the total radiated power is increased by free-space power combining. Since optical phase modulators are readily available in planar lightwave circuit technology and do not need to scale with RF frequency, planar optic integration is simplified compared to photonic truetime delay beamforming. However, phase fluctuations due to thermal and mechanical influences become a major issue if fiberoptic components are used and necessitate the implementation of a phase control circuit. Since direct detection of the terahertz phases is not feasible, an alternative approach is needed. In this paper, a concept for controlling the terahertz phases using a lower-frequency reference tone generated by a second set of infrared lasers is proposed and a simplified system-theoretical model is developed and analyzed. DWG1, DWG2
TD(18)07067 Data from Social Sources in Cellular OAM Sergio Fortes, David Palacios, Inmaculada Serrano, Raquel Barco The amount of social information that can be found online has increased exponentially in the past years. Social networks, calendars, event aggregators, etc. provide a huge amount of details about past, present and future social events such as concerts, sport matches, parades, etc. These event are directly related to the presence of crowds, demand increases and equipment overload in the networks. Therefore, their details can be automatically captured from the Internet automatically and then applied to support multiple aspects of the Operations, Administration and Maintenance (OAM) of cellular networks . In this way, the present work proposes a system for the automatic processing of this type of social data, presenting its different stages and providing  an approach to link such information with the network elements and their performance. Then, a showcase demonstration of the approach is provided, establishing the principles for its use in other OAM activities. DWG3
TD(18)07068 Polarimetric Diffuse Scattering Channel Measurements at 60GHz and 26GHz Alberto Loaiza, Timothy Pelham, Di Kong, Lawrence Sayer, Victoria Sgardoni, Fai Tila, Evangelos Mellios, Mark Beach, Andrew Nix, Gerhard Steinböck When surfaces are rough or include multiple small-scale features and discontinuities, diffuse scatter becomes a significant propagation mechanism in wireless links. Traditionally, in the sub 6GHz bands, surface interactions were modelled as specular reflection. However, higher frequency waves tend to react differently to reflections from building surfaces. For millimetre waves (mmWaves), the specular reflection component remains but more pronounced diffuse components will appear as well, which means that for a given angle of incidence, following the surface interaction, significant power may spread over a wide range of scatter angles. Propagation models that were useful for planning 4G networks will become less useful in 5G mmWave networks as there is a requirement for more deterministic models. This is because spatial resolution is much higher when using millimetre wavelengths, which is important when considering directional multi-antenna arrays for beamforming and beamtracking in order to mitigate higher propagation losses. This paper presents the results of an extensive measurement campaign that demonstrates that diffuse scattering can be a dominant propagation mechanism for mmWave links. With an aim to evaluate the frequency dependency of this propagation mechanism, all measurements were conducted at 26GHz and at 60GHz. Utilising a large measurement bandwidth (up to 2GHz) it is shown that multipath caused by nearly co-incident signals may create small scale fading effects, which affect the flatness of the channel frequency response significantly. It is also shown that as a result of these multipath nearly co-incident signals the cross-polarisation ratio (XPR) may vary largely across the channel bandwidth. DWG1
TD(18)07069 Tri-Band Mm-wave Directional Channel Measurements in Indoor Environment Enrico Vitucci, Marco Zoli, Ke Guan, Franco Fuschini, Marina Barbiroli, Thomas Kuerner, Vittorio Degli Esposti A measurement campaign has been carried out in a reference indoor environment – a medium-size meeting room – using an ultra-wideband channel sounder operating at 3 different frequency bands: 10 GHz, 60 GHz and 300 GHz. Automatic rotational units are used at Tx and Rx side to perform a full horizontal scanning with directional antennas, in order to achieve a double-directional channel characterization. Preliminary results show that multipath is mainly affected by few single or double-bounce components, and significant contributions may come from objects other than the walls, e.g. TV monitor and entrance door. All these contributions are clearly identifiable at all the considered frequencies, although they appear to be stronger at higher frequencies compared to 10 GHz. The radio channel’s multipath richness appear to decrease with frequency, especially when comparing 60 GHz to 300 GHz. DWG1
TD(18)07070 Power delay profile modelling in indoor environments using the VEFIE Ian Kavanagh and Conor Brennan The Volume Electric Field Integral Equation is used to model propagation in indoor environments. Solving the equation over a range of frequencies allows a power delay profile to be generated by applying the inverse Fourier transform. The results thus obtained are compared to simple commonly used empirical methods, as well as results obtained using wide band measurement data. The effect of various numerical parameters (discretisation size, frequency spacing and bandwidth, filtering) are investigated as is the use of the Hilbert transform to ensure causality. DWG1
TD(18)07071 Cell-Free Massive MIMO with Limited Backhaul Manijeh Bashar and Alister Burr We consider a cell-free Massive multiple-input multiple-output (MIMO) system and investigate the system performance for the case when the quantized version of the estimated channel and the quantized received signal are available at the central processing unit (CPU), and the case when only the quantized version of the combined signal with maximum ratio combining (MRC) detector is available at the CPU. Next, we study the max-min optimization problem, where the minimum user uplink rate is maximized with backhaul capacity constraints. To deal with the max-min non-convex problem, we propose to decompose the original problem into two sub-problems. Based on these sub-problems, we develop an iterative scheme which solves the original max-min user uplink rate. Moreover, we present a user assignment algorithm to further improve the performance of cell-free Massive MIMO with limited backhaul links. DWG2
TD(18)07072 A unified channel model for terrestrial and non-terrestrial networks Tommi Jämsä, Guo Bolun,  Mingming Gan, Gerhard Steinböck 3GPP has started a study item on non-terrestrial networks, i.e. networks using and airborne or spaceborne vehicle for transmission. One of the objectives of the study item is related to radio channel models as follows: “Study the feasibility of adapting the 3GPP channel model for non-terrestrial networks. If needed study new channel models.” The current 3GPP channel models have been designed for cellular communications, and they are insufficient for radio links between earth terminal and satellite or high-altitude platform station (HAPS). On the contrary, ITU has specified channel models for satellite links. These two models are fundamentally different, and a significant effort is needed for harmonization of them. This TD discusses the differences between the cellular channel models specified in 3GPP and the satellite channel models specified in ITU, and proposes a unified approach for combining the satellite and cellular channel models into a single channel model framework. The unified model´should enable fair comparison of cellular, HAPS, LEO and GEO satellite links and networks. DWG1
TD(18)07073 Impact of rough surface scattering on stochastic multipath component models Josef Kulmer, Fuxi Wen, Nil Garcia, Henk
Wymeersch, Klaus Witrisal
Multipath-assisted localization makes use of specular multipath components (MPCs), whose parameters are geometrically related to the positions of the transceiver nodes. Diffuse scattering from rough surfaces affects the observed angle and delay profiles of specular reflections. Based on the effective roughness approach, the angular delay power spectrum can be calculated as a function of location parameters, which—in a next step—could be useful to accurately characterize the positionrelated information of MPCs. The calculated profiles follow reported characteristics of stochastic multipath models, i.e. Gaussian shape in the angular domain and an exponential shape in the delay domain. The resulting angular and delay spreads are in an equivalent range to values reported in literature. DWG1, EWG-LT
TD(18)07074 Resource Allocation in Wireless Mesh Networks Arie Reichman, Shahaf Wayer, Miri Prieser A wireless mesh network operating in multiple access scheme that is a combination of FDMA, TDMA and OFDMA, is presented. The scheme has several frequency bands, using time slots and OFDMA modulation. The system manager allocates to the links connecting network nodes resources of frequencies, time slots and subcarriers avoiding collisions among links. The TD presents the rules to avoid collisions and algorithms of resource allocation. DWG2, DWG3