11th TM – Gdansk, Poland, September 4 – 6

TD # Title Author(s) Abstract WGs
TD(19)11001 Design and Implementation Aspects of a 28 GHz Channel Sounder for Dynamic Propagation Characterization Harsh Tataria, Erik Bengtsson, Peter C. Karlsson, Ove Edfors, and Fredrik Tufvesson A pre-requisite for the design of future wireless systems is the understanding of the involved propagation processes, and derivation of insightful models. In this paper, we present a novel 28 GHz massive multiple-input multiple-output (MIMO) channel sounder for measuring dynamic propagation behavior. Based on the switched array principle, our design is capable of characterizing 256×128 dual polarized channels with a switching rate of approximately 10 us. Unlike previous systems, this extraordinary angular resolution is complemented with a 1 GHz measurement bandwidth enabling nanosecond delay resolution. To this end, a complete MIMO snapshot can be acquired in real time with 380 ms, in sharp contrast to tens of minutes with rotating horn antenna sounders. The short measurement time combined with the high phase stability of the 28 GHz radio frequency up/down-conversion chains facilitates phase-coherent measurements. This allows for tracking of multipath behavior over time to investigate the temporal dependencies of channel parameters. Overall, the paper discusses the design and implementation aspects of sounder, and presents a plan for future work in order to measure the dynamic large/small-scale fading propagation parameters. DWG1: Radio Channels,DWG2: PHY Layer,EWG-OTA: Over-The-Air testing
TD(19)11002 Evaluation of a Wideband Pattern-Reconfigurable Multiple Antenna System for Vehicular Applications Jerzy Kowalewski, Jonathan Mayer, Tobias Mahler, and Thomas Zwick A multiple-input multiple-output (MIMO) antenna system consisting of two pattern reconfigurable antennas is presented in this paper. The reconfigurable antennas consist of coplanar waveguide (CPW) feed and two ”c” formed radiators per antenna, placed on two sides of central feed conductor. Three directivity patterns per antenna are reconfigured by switching two p-i-n diodes, thus selecting the radiator. Presented antenna has a bandwidth of 2.1-2.87 GHz (31% fractional bandwidth) covering different mobile services. As a proof of concept a prototype of this antenna has been fabricated and measured. The gain variation between different states is very small and peak gain of 7.3 dBi is achieved. The measurement results correspond well with the simulation results in terms of S-parameter and radiation. DWG1: Radio Channels,EWG-OTA: Over-The-Air testing
TD(19)11003 5G Safety: A scientific response to an increasingly polarized debate Moray Rumney The advent of 5G has renewed public interest in the safety of cellular communications. So as scientists how should we evaluate 5G in terms of safety? Is it a threat or could 5G technology actually lead to reduced exposure were it used to replace what we use today? This paperwill investigate what is changing with 5G towards an understanding of how wide-scale 5G deployment will change RF exposure to the general public, as well as an assessment of the corresponding need to develop more sophisticated exposure verification procedures than are in place today. In addition, there will be a review of the ongoing debate and scientific evidence surrounding the veracity of existing safety limits which are based on purely thermal effects. DWG1: Radio Channels,EWG-OTA: Over-The-Air testing,EWG-RA: Radio Access
TD(19)11004 A statistical study of atmospheric circumstances on microwave links E. Van Lil, R. Van Malderen In a previous paper, we investigated the worst case scenario of the influence of atmospheric circumstances on the propagation of microwave links. In this document, we will investigate this problem from a statistical point of view. This allows to quantize the probability of unlikely events to happen, and their impact on the quality of the transmission DWG1: Radio Channels
TD(19)11005 Mapping between Average SINR and Supported Throughput in 5G New Radio Small Cell Networks Anderson R. Ramos, Bruno C. Silva, Marisa S. Lourenço, Emanuel B. Teixeira and Fernando J. Velez The introduction of small cells through the addition of low-power base stations to existing macro-eNBs has been explored as an easy and cheap solution to increase capacity in hot spots with high user demand, to fill in areas not covered by the macro network and to improve network performance and service quality in 4G and 5G New Radio (NR) networks. The combination of large macro-cells with small cells, generating a heterogeneous network, provides increased bit rates per unit area. This paper explores fundamental aspects of the mapping

between the average Signal to Interference plus Noise Ratio (SINR) and the supported throughput in a context of 5G NR Small Cell Heterogeneous Networks operating at 2.6 GHz, 3.5 GHz and 5.62 GHz, through a mapping between threshold values for the SINR and Modulation Coding Schemes to obtain values for the PHY throughput, following the technical specifications given by Release 15 of the 3rd Generation Partnership Project for 5G NR while considering a bandwidth of 100 MHz and Sub Carrier Spacing (SCS) of 60 kHz. By analysing the results one concludes that there is a one-to-one correspondence between the average SINR and the supported throughput, with an enhanced behaviour for cell radii longer than the ratio between the breakpoint distance and the co-channel reuse factor.

DWG3: NET Layer
TD(19)11006 Validation of Test Environment in Simple Sectored MPAC Setups for Over-the-air Testing of 5G Communication Systems Wei Fan; Fengchun Zhang Over-the-air radiated testing is seen as inevitable for 5G antenna systems. Simple-sectored multi-probe anechoic chamber (SS-MPAC) setup is a potential testing candidate to evaluate 5G antenna systems under real-world propagation conditions. Validation of emulated channel models in the practical SS-MPAC setup is essential, since it is important to assure the target channel models are correctly emulated. In this paper, the objective is to detect the joint-angle-delay power profile of the reproduced channels in the SS-MPAC setup, where two joint angle-delay estimation algorithms are discussed, i.e. an existing algorithm with high computation complexity as the reference method and a novel low-cost sequential one dimensional algorithm. Both numerical simulations and experimental verification measurements in a preliminary SS-MPAC setup are provided to validate the two discussed algorithms. The proposed sequential one dimensional search method is demonstrated to be highly accurate and effective, and therefore recommended for validation measurements in the SS-MPAC setups. Measurement setup and procedure for test environment validation of the SS-MPAC setups are discussed as well. DWG1: Radio Channels,EWG-OTA: Over-The-Air testing
TD(19)11007 New Measures of Service Reliability for Shared Mobile Networks – Reporting from the


Jacek Kibilda This document reports on the work progress and accomplishments of the Short Term Scientific Mission by Dr Jacek Kibilda to the Laboratory of Signals and Systems at CentraleSupelec/University Paris-Saclay, Gif-Sur-Yvette, France. The objective for the visit was to establish collaboration between Trinity College Dublin and CentraleSupelec on the topic of reliability definitions, assessment and implementation within the context of future shared mobile networks. DWG3: NET Layer
TD(19)11008 Antenna Correlation Under Geometry-Based Stochastic Channel Models Yilin Ji, Wei Fan, Pekka Kyösti, Jinxing Li, and Gert Frølund Pedersen Antenna correlation is an important measure for designing multiple-input multiple-output (MIMO) antenna systems. A lower antenna correlation indicates a better MIMO performance that can be achieved with the underlying antenna systems. In the antenna design industry, it is very common to evaluate the antenna correlation with isotropic or non-isotropic (e.g. Gaussian-distributed) angular power spectrum as baselines. Channel models developed in the propagation field, such as the geometry-based stochastic channel model, can also be used to approach a more realistic results. In this paper, the analytic forms for the antenna correlation based on the channel transfer function and the angular power spectrum are derived, respectively, with their similarities and differences explained. Moreover, a numerical example is also given with a standard channel model. DWG1: Radio Channels
TD(19)11009 Macrodiversity solution for mmWave communications in indoor scenario Enis Kocan, Aleksandra Lopusina, Milica Pejanovic-Djurisic In order to achieve the required high data rates for enhanced mobile broadband (eMBB) type of generic services, upcoming 5G cellular systems will deploy mmWave communications in small-cell outdoor and indoor environments. Communications at these frequency ranges have to cope with high propagation path-loss and link outages caused by blocking effect from different obstacles, including human body. Thus, in this paper we examine efficiency of macrodiversity (MD) solution for coping with these deteriorating effects. In order to avoid frequent switching among base stations (BSs), which are in the communication range of a mobile station (MS), we analyze the best decision criteria for selection of a proper link, based on known channel quality indicators (CQIs). Using ns-3 module for mmWave communications, we model downlink (DL) communication at 28GHz in mixed-office scenario, with both self-blockage and dynamic blockage included. In terms of MS mobility, three real-case scenarios are assumed, each with several different BS and blocker densities. The obtained results have confirmed efficiency of MD schemes for improving performance of mmWave communication systems in indoor environment. EWG-RA: Radio Access
TD(19)11010 Predicting the Required Computational Capacity in C-RAN networks by the use of different Machine Learning strategies Rolando Guerra-Gomez, Silvia Ruiz-Boqué, Mario Garcia-Lozano, Joan Olmos In this work three machine learning strategies: Medium Gaussian Support Vector Machine (SVM), Time-Delay Neural network (TDNN) and Deep Leaning using Long Short-Term Memory (LSTM) have been studied, implemented and compared to predict traffic variations and consequently changes in the Required Computational Capacity for C-RAN networks. The algorithms have been tested on a realistic C-RAN deployment using Vienna Scenario. DWG3: NET Layer
TD(19)11011 Measurements and Cluster-Based Channel Modeling for 5G Massive MIMO Communications in Indoor Hotspot Scenarios Jianzhi Li, Ruisi He, Bo Ai, Mi Yang, Zhangdui Zhong Characterization and modeling of massive multiple-input multiple-output (MIMO) channel has been one of the research hotspots in the field of wireless communications. One important feature of massive MIMO channel is the spatial non-stationarity. To statistically model the spatial non-stationary massive MIMO channels, a cluster-based channel model is proposed in this file. The model incorporates both inter-and intra-cluster properties and the cluster evolution over the large-scale array. A hybrid data processing scheme is applied to extract the multipath components (MPCs) and clustering the MPCs over a large-scale antenna array. The global angular spread, cluster angular spread, and cluster delay spread are modeled with Lognormal distributions. Observed cluster length and MPC length within clusters, which are introduced to describe the cluster existence over the array and MPCs existence within the cluster respectively, are statistically modeled with the Exponential distributions. Moreover, both cluster and MPC arrival intervals, which are used respectively to describe the cluster occurrence position on the array and MPC occurrence position within the cluster, can be statistically modeled with the Uniform distributions. Finally, the model implementation is validated by comparing different channel performance metrics between measurements and simulations DWG1: Radio Channels
TD(19)11012 Multi-band Vehicle to Vehicle Channel Measurements from 6 GHz to 60 GHz at “T” Intersection Diego Dupleich, Robert Müller, Christian Schneider, Sergii Skoblikov, Jian Luo, Mate Boban, Giovanni Del Galdo, and Reiner Thomä We introduce simultaneous multi-band ultra wide-band double-directional measurements at 6.75 GHz, 30 GHz, and 60 GHz in a corner scenario at a “T” intersection in an urban environment. We analyse the influence of the dynamics from LOS to NLOS on the large-scale parameters, showing that the propagation channel offers similar scattering opportunities at the sub-6 GHz and the mm-wave bands. In addition, we discuss the possibility of utilizing the directional information from sub-6 GHz to steer beams in the mm-waves bands. DWG1: Radio Channels
TD(19)11013 On Simple Scattering Models and the GGX Directional Model for Point Cloud Predictions Jean-Frédéric Wagen TD(19)10032 proposed a single formulation to simplify the use of specular reflection and Degli-Esposti’s single-lobe directional scattering (Eq. in Fig 3.33 Chap 3-draft of the IRACON’s book) for radio propagation channel modeling. The proposed formulation, called GGXS,

is inspired from many contributors to COST IRACON, the specular reflection from smooth surface, the radar equation and the computer graphics GGX model. The GGXS is reciprocal and leads to well-known equations for very small or large and smooth or rough facets. The GGXS is then claimed to fit the results for facets of any size and any roughness. A specular contribution from many flat facets is obtained by simply adding coherently the GGXS field components; the pre-processing a point cloud to aggregate the flat facets can be avoided. The GGXS is based on two fitting parameters: a material attenuation (AR [dB] = 0 dB for PEC) and a roughness attenuation (As [dB] = 0 dB

for smooth surface). A MATLAB code is provided upon


DWG1: Radio Channels
TD(19)11014 Theoretical and Emulated Performances of MANETs using TDMA: Preliminary Results Yann Maret, Jean-Frédéric Wagen, Gilles Waeber, Victor Adalid, François Buntschuu MANET or VANET using TDMA offer the possibility to implement guaranteed QoS under a given scenario. Theoretical performance results are derived and compared to results from emulations using the open source EMANE framework. Work in progress are reported. DWG3: NET Layer,EWG-RA: Radio Access
TD(19)11015 Influence of User Dynamics on Small-Scale Fading Characteristics in Off-Body Channels Kenan Turbic and Luis M. Correia This paper investigates the influence of user dynamics on small-scale fading characteristics in off-body channels. The effects of both user’s linear forward motion and the periodic wearable antenna displacement due to changes in the posture are considered for walking and running. The time-variant Doppler shift exhibited by signals arriving from different spatial directions is analyzed for wearable antenna placements on the chest, wrist and lower leg, chosen for their different motion dynamics. A strong influence of the on-body placement is observed, with antennas on the arms and legs yielding up to 2.2 times higher maximum Doppler frequency than with antenna on the torso. Furthermore, the small-scale fading dynamics for antennas on the arms and legs vary considerably during the motion cycle, where one can clearly distinguish between slow and fast phases. The latter is found to yield up to 4 times as high level-crossing rate than the former for antenna placement on the lower leg. These findings suggest that the periodic antenna displacement has an important effect on small-scale fading dynamics in off-body channels and should not be neglected, which is typically the case in literature. DWG1: Radio Channels,EWG-IoT: Internet-of-Things
TD(19)11016 Improved 2-Ray Model for Overwater Propagation Channels: Modeling the Instantaneous Variations in the Received Signal Strength Ghassan Dahman, Denis Couillard, Marie-Eve GrandMaison, Gwenael Poitau, and Francois Gagnon Based on analyzing two-day ship-to-shore propagation measurements performed simultaneously at two frequency bands (1.39 GHz and 4.5 GHz), we extract the small-scale fading (SSF) and show that the higher the frequency, the larger the amplitudes of the SSF. Consequently, we introduce a modification to the 2-ray model so that the behavior of the SSF at different frequency bands is captured. We model the effect of the randomness and the unknown dynamic details of the propagation environment as a zero-mean Gaussian random variable which is then superimposed on the length of the rays in the traditional 2-ray model. For the measured environment, it is found that a standard deviation in the sub-centimeter range is able to almost replicate the behavior of the observed SSF at these two bands. DWG1: Radio Channels
TD(19)11017 Extending the ITU-R P.530 Deep-Fading Outage Probability Results to SIMO-MRC and MIMO-MRC Line-Of-Sight Systems Francois Gagnon, Ghassan Dahman, and Gwenael Poitau In this contribution, we propose a method extending the deep-fading outage probability results of the ITU-R P.530 [1] to the SIMO-MRC (maximum ratio-combining) and MIMO-MRC cases. By deducing the similarity between the analytical expressions of correlated Rayleigh fading and the ITU-R P.530 formulations, we utilize the ITU-R P.530 correlation information and the results of [2], [3] in order to estimate the outage probability of SIMO-MRC and MIMO-MRC systems. Finally, we demonstrate the significant reduction (of several orders of magnitude) in the worst month deep-fading outage probability that can be achieved using SIMO-MRC and MIMO-MRC for different fading depths and antenna spacings. DWG1: Radio Channels
TD(19)11018 A Real-time Computational Resource Usage Optimization in C-RAN Mojgan Barahman, Luis M. Correia and Lúcio S. Ferreira This paper presents an approach for the optimized utilization of computational resources in a cloud radio access network’s baseband unit pool. The model relays on the concept of bargaining in cooperative game theory and allocates computational resources based on the instantaneous requirement of bases stations. The model guarantees a minimum amount of computational resources to be allocated to prevent the crashing of baseband units. In addition, the baseband units are prioritized based on the quality of service requirements, in case of lack of resource when not all the demand can be served. Several metrics are used in order to measure the performance of proposed model in a test scenario; in which, a baseband unit pool covers seven cells each generating a different traffic profile with a mixture of heterogeneous services. Amount of allocated resources is monitored for all the baseband units in a tidal traffic condition. Simulation results confirm that the amount of allocated computational resources is adopted to the baseband units’ instantaneous demand and according to the priority level of the running services. Moreover, numerical results show that the baseband units’ demands are fulfilled more than 98% without any processing delay, by using only 43.5% of the baseband unit pool’s capacity. DWG3: NET Layer
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TD(19)11020 Human Body Influence on UWB Channels: Evaluation of Channel Measurements Thomas Wilding, Ulrich Mühlmann, Klaus Witrisal We investigate the UWB channel in off-body conditions, where a mobile device is positioned on-body and an anchor, acting as infrastructure, is located off-body. Due to the high time resolution achievable with UWB signals it can be assumed that the human body is the main source of interference on the line-of-sight signal. We investigate the possibilities of deterministic and stochastic characterization of the UWB channel to allow modeling of the interaction between the antennas of the mobile device and the human body in terms of coupling as well as scattering, shadowing and obstruction. As basis of the channel characterization we use channel sounder measurements obtained in an indoor environment with an optical tracking system used to record the position of the main body parts as well as the mobile device and anchor position and orientations as ground truth. DWG1: Radio Channels,SEWG-IoT: Internet-of-Things for Health,
TD(19)11021 Performance Evaluation of Direct-Link Backhaul for UAV-Aided Emergency Networks German Castellanos, Margot Deruyck, Luc Martens, Wout Joseph Today’s wireless networks provide us reliable connectivity. However, if a disaster occurs, the whole network could be out of service and people cannot communicate. Using a fast deployable temporally network by mounting small cell base stations on unmanned aerial vehicles (UAVs) could solve the problem. Yet, this raises several challenges. We propose a capacity-deployment tool to design the backhaul network for UAV-aided networks and to evaluate the performance of the backhaul network in a realistic scenario in the city center of Ghent, Belgium. This tool assigns simultaneously resources to the ground users – access network – and to the backhaul network, taking into consideration backhaul capacity and power restrictions. We compare three types of backhaul scenarios using a 3.5 GHz link, 3.5 GHz with carrier aggregation (CA) and the 60 GHz band, considering three different types of drones. The results showed that an optimal UAV flight height (80m) could satisfy both access and backhaul networks; however, full coverage was difficult to achieve. Finally, we discuss the influence of the flight height and the number of requesting users concerning the network performance and propose an optimal configuration and new mechanisms to improve the network capacity, based on realistic restrictions. DWG3: NET Layer
TD(19)11022 A Spectrum Sharing Optimisation Mechanism for D2D Applications in Factories of the Future Idayat O. Sanusi, Karim M. Nasr and Klaus Moessner In this paper, we present a spectrum sharing scheme for Device to Device (D2D) deployments in a wireless Internet of Things (IoT) environment targeting factories of the future (FoF). Interference management for this scheme relies on the relative distance between participating users or devices. The D2D links can access spectrum by sharing resources with cellular users or by using dedicated channels. The presented scheme maximises the throughput of admitted D2D links without compromising the Quality of Service (QoS) requirements of users in the network. An optimisation approach is adopted to solve the spectrum sharing problem resulting in an efficient allocation and throughput maximisation for all participating users and devices. DWG3: NET Layer,EWG-RA: Radio Access
TD(19)11023 Scenario Performance Classification for Highway Vehicle-to-Vehicle Communications Thomas Blazek, Manuel Lindorfer, Mehdi Ashury, Gerald Ostermayer, Christoph F. Mecklenbräuker The concept of Vehicle-to-Everything communications (V2X) will be an important driver in the proliferation of autonomous vehicles, as well as one of the first ubiquitous deployments of an Internet-of-Things (IoT) concept. As such, it is expected to play a vital role in the concept of a smart city. V2X communications is however a challenging field due to the highly dynamic network and difficult wireless channel conditions. Hence, a thorough analysis of the achievable performance is essential. In this paper, we analyse the scenario of a densely populated highway, and assess the achievable performance for safety-critical communications both in terms of point-to-point performance, as well as in terms of interference patterns. We adapt stochastic models for both use-cases, and employ the information bottleneck method to reduce the model complexity. Then, we apply Akaike’s Information Criterion (AIC) to find the optimal trade-off between model accuracy and model complexity. Finally, we present a combined stochastic model that uses 6 different parameter sets for the point-to-point link, and 6 parameter sets for the interference link. EWG-IoT: Internet-of-Things
TD(19)11024 Utilization of the V2X Radio Channels Temporal Stationarity for Communication and Radar Sensing Daniel Czaniera, Steffen Schieler, Reiner S. Thomä, Giovanni Del Galdo In this paper, we investigate the possibilities of utilizing the stationarity of the vehicle to everything (V2X) radio channel for applications in the field of communication as well as passive radar. The stationarity can be interpreted as a measure of how severely the radio channel changes. We compute it in temporal domain using the so-called generalized local scattering function (GLSF) and its collinearity. Knowing about the stationarity can enable us to adapt communication and passive radar system to make them more efficient and reliable at the same time. DWG1: Radio Channels
TD(19)11025 Smart-City Approaches in the Campus: The University of Málaga Case Sergio Fortes, José Antonio Santoyo-Ramón, Eduardo Baena, David Palacios, Rocío Mora-García, Miguel Medina, Patricia Mora, Raquel Barco University campuses typically consists on large areas with buildings, roads, parks, water and electricity distribution systems, etc. occupied most of the time by a large number of people. This often makes them equivalent to small cities in every right, which can highly benefit of smart-city approaches in order to improve their sustainability and well-being. Being a huge part of their population composed of students, researcher and professors, they are also a highly suitable places for research and education on smart-city applications, being the perfect playground for innovations in this area. In this line, this work presents the main approaches followed by the University of Málaga in terms of sustainability, education and research activities in the field of smart-city, presenting its approach in terms of IoT infrastructure and assessing its research initiatives and the involvement of the university community. EWG-IoT: Internet-of-Things
TD(19)11026 Cluster Characteristics and Dense Components in Industrial Environments Raffaele D’Errico In this TD we present the results of a channel characterization in a machinery room. Inter- an intra-clusters characteristics are presented. Dense multipath components are analyzed. DWG1: Radio Channels
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TD(19)11028 Adaptive User Grouping Based on EVM Prediction for Efficient & Robust Massive MIMO in TDD Wael Boukley Hasan, Paul Harris, Henry Bromell, Angela Doufexi & Mark Beach Massive multiple-input, multiple-output (Ma-MIMO) offers significant capacity improvements for sub-6GHz wireless access. Evaluating the practicalities for real-world deployments and identifying solutions is the next critical step in the roll-out of this technology. Here novel adaptive user grouping algorithms for a single cell Ma-MIMO scenario are proposed and shown to further enhance performance. For the first time, the methodology addresses the interference caused by the user channel vectors as well as hardware impairments. Here, this is uniquely achieved by extracting the Error Vector Magnitude (EVM), and three different methodologies are applied to address specific wireless connectivity objectives. The first, maximizes the spectral efficiency which is more desirable for cellular networks. The second, maximizes the number of users for low data rate bearers, which is suitable for the Internet of Things (IoT). Whilst, the third approach focuses on specific quality per user, for applications such as wireless cameras at major cultural or sporting events. Importantly, real-world experimental data-sets have been used to evaluate the proposed user grouping algorithms. EWG-RA: Radio Access
TD(19)11029 Performance Evaluation of UAV-Aided Mobile Networks by means of Ray Launching generated REMs Silvia Mignardi, Maximilian James Arpaio, Chiara Buratti, Enrico Maria Vitucci, Franco Fuschini, Roberto Verdone Unmanned Aerial Vehicles (UAV) are increasing attention as enablers for many technical applications and services, a trend likely to continue in the next future. In this regard, using Unmanned Aerial Base Stations (UABSs), i.e. base stations carried by UAVs, is one of the most promising means in 5G applications so as to offer coverage and capacity to those users that are not being served by traditional base stations. We are considering a UAV dynamic trajectory design that accounts for the actual position of unsatisfied users grouped in clusters. The trajectory is computed by a central controller as a function of the distance of the UABS from the next cluster, user density, energy consumed by the drone and spatial fairness. With respect to previous papers, we propose a novel approach to the design of the UABS trajectory that accounts for both the quickly varying user demand and precise Radio Environmental Map information based on ray launching techniques for RF propagation and narrow band estimation. Furthermore, we consider different possible antenna models installed on multiple UABSs. Since these techniques impact the link between UABSs and ground users, network throughput and coverage range are affected in different ways for each solution. The design of the trajectory is combined with a proper Radio Resource Management strategy, with the aim to improve the sum throughput of the network. Simulation results will show for each case the performance achieved by the system. DWG3: NET Layer
TD(19)11030 Coordinated beamforming with sparse channel matrix estimation in Cloud-RAN Charles Wiame, Claude Oestges, Luc Vandendorpe In this paper, a stochastic geometry-based model is proposed to analyze the performance of dense cloud radio access networks. In this model, remote radio heads (RRH) are assumed to estimate channels of user

equipments (UE) located within a certain distance only. Maximum ratio transmission (MRT) is employed as beamforming strategy to serve the estimated UEs. The coverage probability of the network is evaluated by means of Monte Carlo simulations and stochastic geometry expressions. The results are derived for both Rayleigh or Ricean fading on the useful links.

DWG1: Radio Channels, DWG2: PHY Layer
TD(19)11031 Path Loss Models and Fading Statistics for C-Band Train-to-Train Communication Paul Unterhuber, Ibrahim Rashdan, Michael Walter The profound knowledge of wireless propagation is essential to neither over- nor underestimate the effect of the surrounding environment and the movement of nodes on the radio propagation and furthermore on the wireless communication between the nodes. To evolve communication standards and test systems we need channel models in representative environments; typical environments for railway communication are railway station, open field and hilly environment. We introduce path loss models and fading statistics based on channel sounder measurement data as a first step towards a geometry-based stochastic channel model (GSCM). The models represent the mentioned typical environments for railway applications. We compare the results with previous published intelligent transportation system (ITS-G5) measurement based models and highlight the differences. DWG1: Radio Channels
TD(19)11032 Realisation of a Mobile Device for Generating an Electromagnetic Curtain for Special Applications Piotr Rajchowski, Krzysztof K. Cwalina, Jarosław Magiera, Alicja Olejniczak, Paweł T. Kosz, Agnieszka Czapiewska, Robert Burczyk, Krzysztof Kowalewski, Jarosław Sadowski, Sławomir J. Ambroziak In the article design and realisation of the technological demonstrator of a mobile device for generating an electromagnetic curtain (AEGIS) were presented, both in the area of hardware and software. The device was designed to block radio communication by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the demonstrator for generating the jamming signal, that were presented in the paper, aimed at assessing the correctness of operation of the device and verification of the parameters of the generated signal. On the basis of obtained results, the ability to jam the cellular systems as well as other radio devices operating in the frequency band from 400 MHz to 2700 MHz was assessed EWG-IoT: Internet-of-Things
TD(19)11033 Vertical and Horizontal Building Entry Loss Measurement in 4.9 GHz Band by Unmanned Aerial Vehicle Kentaro Saito, Qiwei Fan, Nopphon Keerativoranan, Jun-ichi Takada User traffic of mobile wireless communication is rapidly increasing in urban areas. Thus, service cell planning becomes an important issue for efficient radio resource usage. Since users are also inside high buildings in those areas, it is important to know the building entry loss (BEL) characteristics from the outside base stations (BSs) of various locations for the purpose. In this paper, we measured the penetration loss of buildings with large windows in the 4.9 GHz band by using a system with an unmanned aerial vehicle (UAV). Our contribution is to clarify the vertical-horizontal BEL characteristics through exhaustive measurements. We also extended the COST 231 BEL model for the vertical-horizontal BEL characteristics, and estimated the model parameters from the measurements. The results showed that the vertical-horizontal domain BEL characteristics were quite different, but that they were not independent. The proposed model improved the root mean squared error (RMSE) of the BEL prediction by approximately 3 dB. This is expected to be utilized for the improvement of cell planning efficiency. DWG1: Radio Channels
TD(19)11034 The analysis of the computation offloading scheme with two-parameter offloading criterion in fog computing Eduard Sopin, Konstantin Samouylov, Luis M. Correia Fog computing provides an efficient solution for mobile computing offloading, keeping tight constaraints on the response time for real-time applications. The paper takes into account the variation of tasks by introducing the joint distribution function of the required processing volume and data size to be transmitted. We propose an offloading criterion based on processing and data volumes of tasks and develop an analytical framework for the evaluation of the average response time and average energy consumption of mobile devices. The developed framework is used in the case study. DWG3: NET Layer
TD(19)11035 RF propagation at 60 GHz in ships Brecht De Beelde, Emmeric Tanghe, Marwan Yusuf, Eli De Poorter, Wout Joseph This paper presents the preliminary results of mmWave channel modeling in a bulk carrier vessel. Using the TG Channel sounder, path loss is measured at 60.48 GHz for different distances between the

transmit and receiving nodes in the engine room and steering control room of the vessel. The path loss at reference distance 2 m is 70.3 dB, which is lower than the free space path loss, whereas the path loss exponent of 2.9 is higher than in free space. The one-slope path loss model can be used to calculate throughput via link budget calculations, which shows that 60 GHz propagation realizes high data rate Line-of-Sight communication in the engine room of a vessel. Due to the highly metallic nature of the propagation environment, reactions make communication possible in an obstructed Line-of-Sight confi
guration, but there is no clear distance relationship.

DWG1: Radio Channels
TD(19)11036 Algebraic Analysis of Non-Stationary Mobile-to-Mobile Channels Using the Theory of Algebraic Curves M. Walter, M. Schmidhammer, D. Shutin Non-stationary channel models play a crucial role in today’s communication systems. Mobile-to-mobile channels are known to exhibit non-stationary behavior caused by the movement of transmitter and receiver. Non-stationarity can be addressed by introducing time-variant stochastic functions such as the time-variant instantaneous Doppler probability density function or time-variant instantaneous characteristic function. An algebraic analysis of time-variant Doppler probability density function in a classical Cartesian coordinate system is only numerically tractable due to trigonometric functions in the resulting expressions. In contrast, it has been shown that using prolate spheroidal coordinates for 2D vehicle-to-vehicle channels the algebraic analysis becomes analytically tractable. In this paper, the analysis is extended to mobile-to-mobile channels. It is shown that the time-variant Doppler pdf can be represented without trigonometric functions. The description of the Doppler frequency in prolate spheroidal coordinates allows to describe it as an algebraic curve. This permits the use of algebraic methods to analyze the Doppler frequency and derive the boundaries of the resulting Doppler pdf. Using the developed tools, we investigated exemplary aircraft-to-aircraft scenarios. However, the methodology can be extended to any aircraft-to- aircraft configuration. DWG1: Radio Channels
TD(19)11037 Interfacing BANs with nano-networks for medical applications Pawel Kulakowski, Krzysztof Wojcik, Kenan Turbic, Luis M. Correia This technical document presents an idea of a nano-network operating inside of a human body and communicating with an external body area network. First, medical applications, where two-way (outside and inside the body) communications are critically important, are described. Then, the proposed network architecture, being a combination of nano- and body area parts, is introduced, with focus placed on interfaces between these two segments. The proper locations for gateway nodes in human veins are considered. Finally, the challenges in the design of the into-body and off-body network parts are discussed. The presented network comprises a revolutionary approach for applied medicine where a medical stuff is able to monitor in real-time the state of a patient vascular system and make actions with the aid of nano-nodes located inside of the patient body. SEWG-IoT: Internet-of-Things for Health
TD(19)11038 Channel Characterization of Indoor Scenarios in sub-THz bands Raffaele D’Errico In this TD we present a channel measurement campaign in the D-band with double steering antennas at both transmitter and receiver sides. Channel characteristics obtained from measurements are presented. DWG1: Radio Channels
TD(19)11039 Estimation of Service Quality Indicators in Cellular Networks Ana Herrera-García, Sergio Fortes, Eduardo Baena, Jessica Mendoza, Carlos Baena, Raquel Barco End-to-end analysis of the cellular network is key for the proper management and dynamic configuration of cellular networks. However, direct monitoring of the application layer performance by the operators is challenging due to the lack of access to both the application servers and the user equipment, as well as the growing use of encryption. To overcome this, the present work proposes a framework for the estimation of service quality indicators based on low-layer metrics and configuration parameters. The performance of the proposed approach is assessed in a real LTE network. DWG3: NET Layer,EWG-RA: Radio Access
TD(19)11040 Characterizing the Relation between Processing Power and Distance between BBU and RRH in a Cloud RAN Marcelo Antonio Marotta , Hamed Ahmadi, Juergen Rochol, Luiz DaSilva, Cristiano Bonato Both In Cloud Radio Access Networks (C-RAN), base stations are replaced by Remote Radio Heads (RRHs) having their signals processed in a Base-Band Unit (BBU). A BBU is limited to processing the signals of RRHs within a maximum distance, determined according to delay constraints. This delay is affected by three factors: (i) the distance between BBU and RRH; (ii) channel conditions; and (iii) processing power available. This letter characterizes the relationship between these factors. Our results show that the processing power must be increased significantly for RRHs experiencing low Signal-to-Noise Ratio (SNR) and/or at a longer distance from the BBU. The good news is that RRHs experiencing high SNR can have their processing take place in the cloud, at significant distances, and still meet tight Bit Error Rate (BER) and latency constraints. These two observations open the door to the possibility of dynamic load balancing mechanisms that change the locus of processing in a C-RAN according to channel conditions and availability of processing resources. DWG3: NET Layer
TD(19)11041 Deep Learning Based LOS/NLOS Identification in Wireless Body Area Networks Krzysztof K. Cwalina, Piotr Rajchowski, Olga Błaszkiewicz, Alicja Olejniczak, Jarosław Sadowski In the article the use of deep learning (DL) in ultra wideband (UWB) Wireless Body Area Networks (WBANs) is presented. Developed approach using channel impulse response allows achieving high efficiency in identifying the direct visibility conditions between nodes in off-body communication compared to the methods described in literature. Effectiveness of the proposed deep feedforward neural network was evaluated on the basis of the measurement data for dynamic scenarios in an indoor environment. The obtained results clearly prove the validity of the proposed DL approach in UWB WBANs and high (over 98.6% for most cases) efficiency for LOS/NLOS conditions classification. EWG-IoT: Internet-of-Things, Localisation and Tracking, SEWG-IoT: Internet-of-Things for Health
TD(19)11042 On spatial loss analysis through physical clusters Julian David Villegas Gutierrez, Claude Oestges Shadowing losses are widely consider as lognormal random variables. In a multi-link scenario, terminals might share similar channel propagation characteristics if they are close enough in distance. This correlation between links is usually modeled as an exponential decaying function of the distance, with a parameter to set the rate of decay. Gudmunson model is an example of such kind of models. While in reality, position (and so, direction) can determine channel characteristics, models that rely on distance assume an isotropic propagation. Another way of modeling losses which takes direction into account, is to think about the density of losses as a scalar spatial field. A particular loss along a path is computed as the line integral of the field over that path. These paths are taken from the physical mapping of the channel parameters (AoD, AoA) and the identification of reflectors. In this article, we investigate spatial loss scalar fields to try to explain the losses that arise from the specular reflection paths. DWG1: Radio Channels
TD(19)11043 Availability of 7 km long parallel backhaul links (18/19 GHz and 71/81 GHz) Christina Larsson, Lei Bao E-band (70/80 GHz) backhaul links are nowadays available with multi-gigabit capacity, unfortunately the high attenuation due to rain is limiting the link lengths to about 2 km. A way to overcome the link length limitation is to set up the E-band link in some sort of carrier aggregation solution together with a conventional backhaul band, usually 18-23 GHz to guarantee availability of critical data transfer also during heavy rain. This is a study comparing long term logging of 7 km long parallel backhaul links with carrier frequency 18/19 GHz and 71/81 GHz. This summary includes a comparison with ITU recommendations and a discussion on which phenomena, more than precipitation, is influencing the availability of these links. DWG1: Radio Channels
TD(19)11044 Physical-Layer Abstraction for Hybrid GNSS and 5G Positioning Evaluations José A. del Peral-Rosado, Olivier Renaudin, Christian Gentner, Ronald Raulefs, Enrique Domínguez-Tijero, Alejandro Fernández-Cabezas, Fernando Blázquez-Luengo, Gema Cueto-Felgueroso, Alexander Chassaigne, David Bartlett, Florin Grec, Lionel Ries, Roberto Prieto-Cerdeira, José A. López-Salcedo and Gonzalo Seco-Granados Hybridization of Global Navigation Satellite Systems (GNSS) and fifth generation (5G) cellular positioning is foreseen as a key solution to fulfill high-accuracy positioning requirements in future use cases, such as autonomous vehicles. The evaluation of the hybrid positioning capabilities implies the physical-layer simulation of observables from both GNSS and 5G technologies. In order to ease the complexity of the resulting system-level simulations, a physical-layer abstraction of GNSS and 5G ranging observables is here proposed. The abstraction of GNSS ranging observables is based on a Gaussian-distributed model of the errors sources, while the abstraction of 5G ranging observables is based on the interpolation of the cumulative density function (CDF) of the ranging errors for certain propagation conditions and signal-to-noise (SNR) levels. Thanks to the exploitation of the proposed physical-layer abstraction, low-complexity system-level simulations are performed to assess the positioning capabilities of GNSS and 5G downlink time-difference of arrival (DL-TDoA) in urban macro-cell (UMa) environments. The simulation results indicate the need to adopt hybrid solutions based on multiple GNSS constellations and 5G DL-TDoA with 100-MHz bandwidth, in order to ensure a horizontal positioning accuracy below 5 m for 95% of cases in outdoor urban environments. Localisation and Tracking
TD(19)11045 Exploitation of 3D City Maps for Hybrid 5G RTT and GNSS Positioning Simulations José A. del Peral-Rosado, Fredrik Gunnarsson, Satyam Dwivedi, Sara Modarres Razavi, Olivier Renaudin, José A. López-Salcedo and Gonzalo Seco-Granados The combination of fifth generation (5G) cellular technologies and Global Navigation Satellite Systems (GNSS) is envisaged to pave the way for the fulfillment of high-accuracy positioning requirements in future use cases, such as in the automotive and smart cities domain. However, these positioning technologies are typically evaluated with independent simulations of statistical channel models for satellite and terrestrial links, which limits the applicability of the performance results. Thus, three-dimensional (3D) city maps are here exploited to simulate coherent satellite and terrestrial links, in order to assess the positioning performance of hybrid 5G and GNSS methods in specific use cases, such as urban canyons. The proposed simulation method is based on the use of 3D city maps to determine the line-of-sight (LoS) conditions of the available satellite and cellular links. These accurate LoS measurements are then considered to assess a hybrid 5G round-trip time (RTT) and multi-constellation GNSS solution in a deep urban canyon. The combination of only one 5G RTT measurement with the GNSS observables is shown to already provide a significant improvement with respect to stand-alone GNSS solutions in terms of positioning accuracy and availability. Furthermore, simulation results indicate that a ranging accuracy of 1 m for this additional 5G RTT measurement is necessary to achieve a horizontal positioning accuracy below 10 m on the 80% of the cases in a deep urban canyon. Localisation and Tracking
TD(19)11046 A Review of 6G Radio Spectrum Opportunities Pekka Kyösti, Marko E. Leinonen, Markus Berg, Aarno Pärssinen In this TD we review characteristics of radio frequency bands and their capability to support communication and other services. Characteristics like, e.g., dominant propagation mechanisms and attenuation effects, existing channel models, and approximate provided system bandwidths, are discussed on high level for frequency bands between 0.3GHz and 30THz. Our intention is to approximate link budgets together with target bit rates and use them to evaluate maximum link distances and capabilities to support for mobility. The work is still in a draft phase and the TD is more like a work plan than a solid scientific contribution. We present the TD in IRACON firstly to gain comments and also to draw attention to utilization and characterization of higher parts of radio spectrum. DWG1: Radio Channels
TD(19)11047 Validation of Numerical Models of Portable Wireless Devices for Specific Absorption Rate Evaluation Balint Horvath, Peter Horvath, Zsolt Badics, Janos Pavo The number of health related internet of things (IoT) devices is rapidly growing. In most cases it is required that these devices connect to a wireless body area network (WBAN), which requires efficient wireless communication capabilities. As these devices are often operated in the vicinity of the human body, one key limiting factor in design is to comply with specific absorption rate (SAR) regulations. In our work we propose a cost efficient near field numerical validation method for IoT-Health devices. The technique is based on input impedance change measurement caused by the perturbation of a control object in the near field of the device. Placing the control object in multiple positions on a scanning grid and applying the Born approximation makes it possible to reconstruct the $\vec{E}^2$ field by deconvolution. In our work we briefly introduce the theoretical background of our validation technique and give an example through a planar inverted F antenna (PIFA) with measurements and simulation. SEWG-IoT: Internet-of-Things for Health
TD(19)11048 “Fog Massive MIMO”: performance analysis Alister Burr, Shammi Islam, Manijeh Bashar and Dick Maryopi In a previous document (TD(19)09086) we have introduced the concept of “Fog Massive MIMO” (F-MaMIMO) as an analogue of “Fog RAN” for ultra-dense radio access networks. Fog-RAN and F-MaMIMO is related to Cloud-RAN in that baseband processing is performed within the network, but is carried out at edge processing units (EPUs) located closer to the network edge rather than in a single central processing unit (CPU), thus avoiding the excess latency encountered in Cloud-RAN. That document however made some simplifying assumptions in the course of its performance analysis: here we relax those assumptions and provide more detailed analysis and simulation results for the performance of F-MaMIMO. In particular we assume linear minimum mean square error (LMMSE) channel estimation and various data detection algorithms, allowing for different numbers of antennas at access points (APs). DWG2: PHY Layer
TD(19)11049 Impact of Unlicensed-band Listen Before Talk Priority Classes in Ultra-dense Scenarios Eduardo Baena, Sergio Fortes, Raquel Barco The rapid proliferation of user devices with access to mobile broadband has been a challenge from both operational and deployment point of view. With the incorporation of new services with high demand for bandwidth such as video in 4K or with very low latency restrictions such as telecontrol, it has been deemed necessary to expand the existing capacity by including new bands, among which the unlicensed 5GHz is a very promising candidate. The operation of mobile communications in this band implies the coexistence with other technologies such as WiFi, which use is widespread. This paper explores the impact of standardized media access techniques in unlicensed 3GPP standard especially LTE-Licensed Assisted Access, in terms of end user Quality of Experience and fair coexistence. EWG-RA: Radio Access
TD(19)11050 Framework For Location-Aware Cellular Management Sergio Fortes, Carlos Baena, Eduardo Baena, Javier Villegas, Muhammad Zeeshan Asghar, Raquel Barco 5G deployments are expected to support precise indoor positioning based on the telecommunication infrastructure. This opens the way to the use of localization of the user equipment as part of the management of the cellular network, including its failure management, planning and optimization. However, having both positioning and telecommunication data (e.g. radio conditions, service performance) from the different user equipment in the network leads to a huge increase in the dimensionality and complexity of the inputs available for cellular management automated algorithms, making them both difficult to define and to computationally costly. Considering this, the present work proposes a framework for the combination and application of localization and network data for the management of cellular networks. DWG3: NET Layer,EWG-RA: Radio Access
TD(19)11051 60 GHz V2I Channel Variability for Different Elevation Angle Switching Strategies Herbert Groll, Erich Zöchmann, Markus Hofer, Hussein Hammoud, Seun Sangodoyin, Golsa Ghiaasi, Thomas Zemen, Jiri Blumenstein, Ales Prokes, Andreas F. Molisch, Christoph F. Mecklenbräuker We report results based on millimeter wave vehicle-to-infrastructure (V2I) channel measurements conducted in an urban street environment, downtown Vienna, Austria. Signal to noise ratios (SNRs) have been acquired at 60 GHz with a bandwidth of 100 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-degrees up-tilt. This configuration was chosen to assess the impact of beam elevation on V2I communication channel variability. We compare three different strategies, namely fixed, geometry-based, and SNR-based beam switching. DWG1: Radio Channels
TD(19)11052 A Bandwidth Scalable Millimetre Wave Over-The-Air Test System with Low Complexity Erich Zöchmann, Terje Mathiesen, Golsa Ghiaasi In this work, we show the design and validation of a testbed for over-the-air testing of millimetre wave equipment. We have extended the frequency capabilities of a baseband channel emulator, that is capable of emulating non-stationary channels, to higher frequencies. To assure that the propagation between devices-under-test and the RF-frontend of the emulator is only a line-of-sight link, we have isolated the devices-under-test in two an-echoic chambers. We have characterized the testbed at 57 GHz by means of frequency sweeps for two artificial cases: when the emulator is replicating a one-tap channel and a two-tap channel. Finally we characterize the system by a reproduction of channels which were acquired during a vehicular millimetre wave measurement campaign, conducted in Vienna in 2018. EWG-OTA: Over-The-Air testing
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TD(19)11054 Deep Learning Architecture for LOS/NLOS identification in real indoor environment. Alicja Olejniczak, Olga Błaszkiewicz, Krzysztof K. Cwalina, Piotr Rajchowski, Jarosław Sadowski Indoor environment can be considered as distinctly detrimental for transmitted signals. As long as the obstacles, such as furniture or architecture elements, may degrade transmission of the signal and consequently, affect the reliability of telecommunication services, it is highly important to compensate that undesirable influence. Hence, identifying LOS/NLOS (Line-of-sight, Non-line-of-sight) conditions is one of the possible methods to improve transmission performance. This paper presents FNN (Feedforward Neural Network) architecture which allows to identify LOS/NLOS with accuracy around 99%. FNN was trained and tested with UWB (Ultra-wideband) data measured in real indoor environment using DWM1000 modules. EWG-IoT: Internet-of-Things, Localisation and Tracking
TD(19)11055 Radio distance measurements errors estimation in various environments Olga Błaszkiewicz, Krzysztof K. Cwalina, Alicja Olejniczak, Piotr Rajchowski, Jarosław Sadowski The main goal of the conducted research was to estimate the errors in radio distance measurements performed by DWM1000 nodes in close proximity, when high level of received signals causes the relation between estimated round-trip time and distance to be nonlinear.

Measurements campaign were carried out in indoor and outdoor environments in four different places, i.e. sitting room, car park, corridor and building’s hall. According to the obtained results the probability density functions of RDMs errors were fitted.

TD(19)11056 Influence of antenna Beamwidth on the observed characteristics of an outdoor vehicular Khalid A Al Mallak, Mark Beach, Tian Loh & Geoffery Hilton Autonomous vehicles will require a very high-speed and low latency communications. 5G will become a strong base to build such network infrastructure making use of millimetre wave (mm-wave) frequencies and the beamforming techniques. This will enable direct communications between the vehicles and also infrastructure and vehicles. To ensure that systems using mm-wave frequencies can be deployed successfully for autonomous vehicles and offer reliable communications, intensive characterisations of vehicular channels is necessary in order to investigate parameters which may directly influence on the operation of communications bearer. This can be done through system level simulations employing actuate and realistic channel model, with parameters extract from real-world measurements. This paper investigates the influence of Doppler shift, Doppler spread and signal attenuation on a vehicle to infrastructure (V2I) communication channel employing a 26 GHz phased array antenna on loan from Anokiwave. This antenna facet acts as a spatial filter, eliminating unwanted multi path components (MPCs) and allows the main beam to be electronically steered. The results show a successful line of sight (LOS) communication between the Base-Station (BS) and the User- Equipment (UE) for up to 150 m distance for a transmitted power of 25 dBm. A stable channel gain was observed during the measurements and related to the proper direction of the beamwidth. Further the results indicated that there is attenuation between 17 and 27 dB when there is a vehicle obscured the LOS connection between the transmitter and the receiver. Moreover, indirect communication such as the non-line of sight scenario NLOS did show reasonable communications from the reflections and scatterings which causes attenuation on the transmitted signals. However, by driving the test vehicle in a car park with almost full of parked cars and at a speed of 5 m/h, very small Doppler shift was observed because the rich scattering and reflections are suppressed by the spatial filtering of the array. DWG1: Radio Channels,DWG2: PHY Layer
TD(19)11057 Enhancing rural 5G network capacity using TVWS delivered from Aerial Platforms Luzango Mfupe, Konstantinos Katzis and Habib Mohammed from a High Altitude Platform (HAP) can provide significant capacity enhancements. Areas served by more than one cell (overlap areas) benefit from the multiplexing gain. Such techniques can be used when delivering TVWS coverage over a large geographical area providing broadband services over many rural and low-income countries of the world where there is poor quality (or no) internet connectivity as well as mobile coverage due to the deficiency of infrastructure, limited core telecommunication network and unreliable electricity supply. This work presents the advantages of employing TVWS spectrum in Ethiopia which has limited internet connectivity across the country and presents a proof of concept of delivering these services from a HAP. It then stresses the technical challenges of developing such a system.
TD(19)11058 Soft Clustering for Effective Signal Detection Krzysztof Cichoń, Hanna Bogucka In the document selected clustering schemes are analysed towards effective collecting and inference based on sensed information. Various types of data is considered to be acquired as well as hard and soft grouping schemes are simulated.