Muriel Muller

CMOS implementation of a TR-UWB receiver Based on Time Delayed Sampling and Correlation method

Recently a new detection method for TR-UWB systems called time delayed sampling and correlation (TDSC) has been proposed. This new method overcomes the major difficulties in a traditional TR-UWB detection method based on a wide band delay line. TDSC is based on a time to space conversion realizable by an analog waveform sampler. In this paper a first prototype is presented designed using low cost CMOS 0.35 mum technology. Simulated results and layout of the first prototype are described.

A New Signal Detection Method for TR-UWB: By Time Delayed Sampling and Correlation (TDSC)

This paper introduces a new signal detection method for Low cost, Low power and Low complexity (L3) TR-UWB systems for medium to low data rate applications such as sensors networks. This new detection method is based on a time_to_space conversion realizable by an analog waveform sampler. This method overcomes the major difficulties in a traditional TR-UWB detection methods based on wide band delay lines. Finally the relaxed timing precision needed in symbol synchronization contributes further to lower the system power consumption. This concept has been validated by simulation with real data from experimental setup. The results will be presented and compared also with other solutions.

RF subsampling GNSS receiver: Potential advantages and feasibility study

The American GPS and Russian GLONASS satellite positioning systems have been operational since the 90s. Other GNSS systems are under development like European Galileo and Chinese Compass systems. Several mass market GNSS products allow users to have their positions, speed and time, but the majority of them are limited to a single standard and do not allow positioning in no coverage areas. Hence, it is very interesting to have a single receiver that includes several positioning systems which is capable of providing precise position indoors and outdoors. This paper deals with a new GNSS receiver architecture for GPS, GLONASS and Galileo radio signals characterized by low power and high sensitivity, also capable of providing outdoor to indoor positioning service. The proposed architecture is based on an RF subsampling down-conversion topology. A fixed subsampling frequency is chosen to properly down-convert the three constellations RF bands to a fixed IF band, which relaxes the IF filter design. A Direct Digital Converter is then proposed to perform quadrature down-conversion to baseband. Simulation results show high gain and low noise for the designed RF front-end and validate subsampling frequency choice through multiband GNSS receiver condition.

An experimental approach to a low-complexity two-step TOA measurement for TR-UWB signals

A proposal for a two-step time of arrival (TOA) estimation based on the Time Delayed Sampling and Correlation (TDSC) method for Transmitted Reference Ultra-wideband (TR-UWB) signals is presented and experimentally tested in a wireless environment. It relies on the sliding correlation over a symbol length, at the coarse step, to find a signal block where the direct path is enclosed. At the second step, the sliding correlation is finely evaluated over this signal block to estimate precisely the beginning of the pulse. The TOA is then evaluated with a high resolution obtained from the relatively high sampling frequency of the metal-oxide semiconductor circuit (CMOS) that implements the TDSC method. This TOA estimator structure is simple, feasible and with a low computing demand.

Optimal correlator size for the TDSC-UWB detection method

This paper studies different aspects of the correlation process for a new TR-UWB detection method called Time Delayed Sampling & Correlation (TDSC). The TDSC concept is based on inter-correlation between two waveforms captured by two time delayed samplers. The objective is to determine different design parameters for silicon integration. In this paper we focus on the length of the correlation window and we give the minimum size of the register file in the waveform samplers; this value insures an optimal detection performance with indoor communication channels. In this work, all the simulations and validation use the IEEE 802.15.3a channel models.

A reconfigurable multistandard GNSS receiver setup operating in L1/L2 bands

Global Navigation Satellite System (GNSS) is widely used around the world. It includes services provided by GPS, GLONASS, GALILEO and BEIDOU. GNSS-based applications use GNSS receivers to collect position, velocity and time information. Thus, the implementation of a multistandard GNSS receiver brings enormous benefits to consumers of wireless services. Besides, developing a reconfigurable receiver allows reducing significantly its power consumption.

Experimental Detection and Synchronisation Validation for a TR-UWB System Based on the Time Delayed Sampling and Correletion Scheme

The detection and synchronization experimental validation of the “Time Delayed Sampling and Correlation” (TDSC) detection scheme for transmitted reference ultra-wideband signals (TR-UWB) is presented. This structure has been proposed to achieve a UWB system with low cost, low complexity and low power consumption for medium to low data rate applications which includes ranging for localization purposes. The scheme is implemented in CMOS technology and a test platform has been designed. Detection of TR-UWB signals and the principle of the proposed synchronization process have been done successfully in both a direct cable connection as well in a wireless system with a real channel. In both cases they were used in the sub GHz band (group 1) and also in the low band UWB signals. Further work and experimental results are also shown for a distance measurement strategy, based on the time of arrival (TOA) using the TDSC scheme.

Development of a compact acquisition system for touch location on a conformable monoport distributed sensor

A compact acquisition system developed for a flexible large area monoport tactile surface is presented in this paper. This sensor requires a single port connection and avoids complicated matrix acquisition system and multiplexing. The tactile surface is based on a coplanar transmission line printedd on a large area flexible substrate. Touching the waveguide generates a reflected signal. A harmonic analysis of this reflected signal at the line input port allows locating the touch event. A compact and low complexity acquisition system has been developed in order to demonstrate the principle and evaluate the feasibility of its integration on the sensor. Theoretical background, design and measurements on the overall sensor are exposed. The acquisition circuit imperfections have been demonstrated experimentally and correction methods have been proposed and implemented. Results are presented, and to assess the precision of the compact acquisition system, they are compared to reference measurements made with a Vector Network Analyzer

Innovative large area touch sensor: Design and tests of a compact acquisition system

A flexible large area touch sensor and its acquisition system are presented in this paper. The sensing device is based on a printed coplanar transmission line on a large area flexible substrate. Having a unique connection port, it avoids matrix connections array. Touching the waveguide generates a reflected wave which is analyzed at the input port in order to extract the position of the touch event. A low complexity acquisition system was developed and tested in the objective of having a compact integrated system. Theoretical background, implementation and results obtained on the overall sensor are presented. We demonstrate here the operation of an integrated acquisition system and compare its performance to Vector Network Analyzer-based operation.