The COST 2100 channel model is a geometry- based stochastic (GSCM) that can reproduce the properties of MIMO channels over time, frequency, and space. In contrast to other popular GSCMs, approach generic flexible, making it suitable multi-user or distributed scenarios. this article concise overview presented. Main concepts are described, together with useful implementation guidelines. Recent developments, including dense multipath components, polarization, multi-link aspects, also discussed.

A channel model for time-variant multi-link wireless body area networks (WBANs) is proposed in this paper, based on an extensive measurement campaign using a multi-port sounder. total of 12 nodes were placed the to measure within created WBAN. The resulting empirical takes into account received power, link fading statistics, and auto- cross-correlations. distance dependence power investigated, modeled by log-normal distribution. autocorrelation function divided decaying component sinusoidal...

In order to implement unmanned aerial vehicle (UAV)-based wireless communications, a better understanding of channels and the corresponding channel characterizations are critical. this paper, air-to-ground (AG) measurements carried out at some candidate frequencies, i.e., 1 GHz, 4 12 24 GHz. With measurement data, crucial parameters comprehensively analyzed. Firstly, based on model in 3rd Generation Partnership Project (3GPP), essential coefficients for modeling path loss, including loss...

This paper investigates the prediction capabilities of a Ray-Tracing tool with advanced features, i.e., diffuse scattering and penetration, in terms angular spreads spectra directional propagation channel. In particular, it highlights behavior dense multipaths, which may represent non-negligible part received power, by comparing simulations experimental data (office laboratory environments). Results show that approach including is able to reproduce multipath spreads, errors around 4 20...

We present an implementation of distributed transmit beamforming using software-defined radios. The nodes synchronize in carrier frequency a pilot signal sent by master node, and employ feedback from the receiver to adjust their phases so as add up coherently at receiver. Our advances state art for all-wireless two important ways. first is extended Kalman filters synchronization slave nodes, which shown be effective despite high local oscillator (LO) offsets typical radios, low duty cycle...

Multiple-input-multiple-output (MIMO) technologies allow high data rates to be obtained, but they suffer from interantenna correlation caused by the limits in spacing. Polarized MIMO systems resolve this problem using colocated perpendicularly polarized antennas that have low correlation. In paper, a single-directional channel model for 2× <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> at 3.6 GHz an indoor environment is presented. The...

We present a fully wireless implementation of distributed transmit beamforming using software-defined radios. Distributed is cooperative transmission scheme whereby number nodes in network organize themselves into virtual antenna array and focus their the direction intended receiver, potentially achieving order magnitude improvements energy efficiency. The main technical challenge realizing these gains precisely synchronizing radio frequency signals cooperating nodes. This idea has been...

In urban areas, GNSS localization quality is often degraded due to signal blockage and multi-path reflections. When several signals are blocked by buildings, the remaining unblocked satellites typically in a poor geometry for (nearly collinear along street direction). Multi-path reflections result pseudo range measurements that can be significantly longer than line of sight path (true range) resulting biased geolocation estimates. If 3D map environment available, one address these problems...

We consider the problem of tracking a receiver using signals-of-opportunity (SOOPs) from beacons and reference anchor with known positions velocities, where all devices have asynchronous local clocks or oscillators. model clock drift at individual by two-state unknown offset skew analyze biases introduced asynchronism in received signals. Based on an extended Kalman filter, we propose sequential estimator to jointly track location, velocity, its parameters altitude information together...

MIMO technologies enable high communication data rates, but suffer from the large antenna spacing that is required to achieve sufficiently low inter-antenna correlation. Cross-polarized systems resolve this problem by using perpendicular antennas. Correlation reduced while keeping antennas co-located. Inter-antenna correlation and cross-polar discrimination(XPD) are two fundamental parameters of these polarized systems. This paper proposes an analytical channel model, which closed-form...

Cross-polarized antenna systems are an attractive way to reduce equipment size while maintaining low interantenna correlation. In this paper, the polarization behaviour of indoor channels is investigated. A measurement campaign has been conducted at 3.6 GHz for a dual-polarized transmitter and tri-polarized receiver in non-Line-of-Sight (NLOS) scenario. The spatial delay characteristics extracted using pertap beamforming algorithm. Distinct paths isolated each wave expressed terms its...

This article investigates the prediction accuracy of an advanced deterministic propagation model in terms channel depolarization and frequency selectivity for indoor wireless propagation. In addition to specular reflection diffraction, developed ray tracing tool considers penetration through dielectric blocks and/or diffuse scattering mechanisms. The sensitivity analysis is based on two measurement campaigns carried out a warehouse office building. It shown that implementation into RT...

We propose a novel distributed expectation maximization (EM) method for non-cooperative RF target localization using wireless sensor network. consider the scenario where few or no sensors receive line-of-sight signals from target. In case of non-line-of-sight signals, signal path consists single reflection between transmitter and receiver. Each is able to measure time difference arrival target's with respect reference sensor, as well angle signal. derive EM algorithm each node makes use its...

Preliminary results on quadrotor control strategies enabling omnidirectional radio frequency (RF) sensing for source localization and tracking are discussed. The use of a requires tight coupling the attitude RF designs. We present controller ramp reference input in yaw (causing rotation quadrotor) while maintaining constant altitude hover or translation. ability to track angle is crucial bearing estimation using received signal strength (RSS) measurements from directional antenna as it...

The multi-frequency propagation in urban environment is investigated this letter. An experimental measurement campaign conducted to simultaneously measure the GSM-900, GSM-1800 and UMTS band of a cellular system suburban environment. shadowing small-scale fading parameters are extracted, correlation these across different frequency bands measured. It shown that coeffcients highly correlated, while completely uncorrelated between bands.

We investigate a computationally and memory efficient algorithm for radio frequency (RF) source-seeking with single-wing rotating micro air vehicle (MAV) operating in an urban canyon environment. present that overcomes two significant difficulties of First, Global Positioning System (GPS) localization quality can be degraded due to the lack clear line sight sufficient number GPS satellites. Second, spatial RF field is complex multipath reflections leading multiple maxima minima received...

A novel approach is proposed to achieve simultaneous localization and mapping (SLAM) based on the signal-to-noise ratio (SNR) of global navigation satellite system (GNSS) signals. It assumed that environment unknown receiver location measurements (provided by a GNSS receiver) are noisy. The 3D map decomposed into grid binary-state cells (occupancy grid) locations approximated sets particles. Using large number sparsely sampled SNR receiver/satellite coordinates (all available from...

Both safety and non-safety applications of vehicular networks rely on accurate position information. However, localization a vehicle in global navigation satellite system (GNSS) denied environment is challenging still open research problem. The 802.11p dedicated short-range communication systems (DSRC), designed for vehicle-to-vehicle vehicle-to-infrastructure communications, can help to solve this In paper, we propose an algorithm self-localize GNSS-denied environment. vehicles driving...

The time variation, i.e., time-selective fading, of on-body channels in body area networks is dominated by the dynamics, which not only contribute to dynamic scattering, but also modify geometry links over time. In this letter, we experimentally investigate Doppler spectra narrowband anechoic (at 2.45 GHz) and indoor 4.2 environments for people walking. dynamics resulting from walking are shown directly affect spectrum, empirical models proposed describe global and/or local spreads.

We propose a novel technique to localize periodic transmitter using single mobile receiver. By having the receiver measure time-of-arrival (TOA) of messages sent by transmitter, is able virtual time-difference-of-arrival (V-TDOA) between different locations along its trajectory. The V-TDOA can then be used in place TDOA measurements various TDOA-based localization methods for transmitter. However, major challenge obtaining an accurate measurement lies separating it from time offset and...

We propose and demonstrate a scalable architecture for distributed receive beamforming. In cluster of N + 1 nodes receiving message from distant transmitter, are designated as amplify-and-forward relays one node is the receiver. The relay apply phase shift to their received signal forward it such that forwarded signals add up constructively at receiver, with SNR scaling linearly N. This approach transforms beamforming problem on "long link" transmitter into transmit "short so number degrees...

Estimating the direction-of-arrival (DoA) of radio frequency sources is essential in many wireless applications. Traditional DoA estimation based on bearing measurements requires multiantenna arrays, which not suitable for portable electronics its large form factor. In this article, we improved a novelty single-antenna-based technique, called virtual arrays. While device moving and continuously receiving signals, can be estimated by measuring intercepted signals at several positions along...

Ultra-wideband communications inside a car are investigates in this paper. Measurements have been carried out typical sedan family two different environments. One of those was one-way narrow street and measurement were taken while moving the street. All measurements varying numbers passengers. Based on measurements, channel model using reverberation chamber theory is proposed. results parameters presented