Jean-Christophe Cousin

Propagation path loss models for LTE-advanced urban relaying systems

Relaying technology - a key technical enhancement in 3GPP LTE-Advanced (3rd Generation Partnership Project Long Term Evolution - Advanced) - has attracted much research interest over the last few years. However, propagation path loss models dedicated to relaying systems are yet to be properly validated. Moreover, the impact of relay antenna height on propagation channel has not yet been adequately studied. This paper presents a measurement-based study which aims to analyze the impact of relay antenna height on path loss channel models. The analysis results demonstrate that BS-RS (Base Station - Relay Station) link path loss decreases with the increase in relay antenna height. Moreover, different propagation models which could be applied for BS-RS link are verified. The analyses show that these models are not completely adequate for relaying deployment. Finally, a new propagation model for relaying deployment which takes into account the impact of relay antenna height is proposed.

Carrier Aggregation of Three OFDM Signals Using a Single Oscillator and I/Q Modulator

In this paper, a novel method is presented, which makes carrier aggregation (CA) using a single local oscillator and an in-phase/quadrature (I/Q) modulator, possible. Three component carriers with orthogonal frequency division multiplexing are generated at 2.2, 2.5, and 2.9 GHz to show the feasibility of the method for the worst case scenario that is the interband CA. A special procedure to compensate the I/Q imbalances specific to this method is explained as well. Moreover, according to Nyquist criterion, the signal should have a sampling rate at least twice the signal highest frequency. In this method, the sampling rate of the digital-to-analog converter is significantly reduced, because, the baseband signal is distributed over negative and positive frequencies. In addition, the demodulation process of these frequency-aggregated signals using a three-phase demodulator is explained and experimental results are presented.

2D indoor localization system using FMCW radars and DMTD technique

A multistatic microwave frequency-modulated continuous-wave (FMCW) radar system used to localize a remote Tag in an Indoor Environment is described. The frequency information extracted from the FMCW data can be processed for the range and the angle-of-arrival (AoA) estimations by computing the average frequency shifts over a fixed sweeping period of time by utilizing the DMTD (Dual Mixer Time Difference) technique. This allows to reduce the sweeping frequency range while maintaining the accuracy.

Indoor Localization System for 2D measurement in European UWB band with single reference position

In this paper a hybrid 2D-Measurement technique is utilized for the estimation of remote position of an active reflector unit (Tag), in terms of radial distance and azimuth angle. Technique is based on Interferometry and FMCW multistatic radar system which operates in the European UWB frequency band. Measurements have been performed in the real indoor environment for line-of-sight case with respect to a single known reference position. Estimated root-mean-square errors are under 1.58cm & 5.2°, respectively. This new technique offers a wide range of application in robotics, industrial automation and medical domain.