UWB application for precision automobile parking system

Abstract

Summary form only given. Extensive research work is being carried out to develop the Ultra-Wideband (UWB) technology for communication applications and to resolve the practical challenges in implementing an efficient UWB communication system utilizing the UWB impulse radio for precision localization. In this project work a scheme is devised for the implementation of the proposed system for precision automobile parking application. The proposed UWB impulse radio system consists of tags for transmitter and fixed nodes provided with both transmitter and receiver (transceiver). For Ultra-wideband localization systems, time-based schemes namely time of arrival (TOA) and time difference of arrival (TDOA) provide very good accuracy due to the high time resolution (large bandwidth) property of UWB signals. Due to the inherent suitability and accuracy of time-based approaches for UWB systems, particularly the TDOA technique, it is proposed as an appropriate UWB localization technique for the precision automobile parking system. In the proposed TDOA localization technique, neighbouring nodes receive radio signals transmitted from the tags and calculate the time of arrival, utilizing the time difference of arrival (TDOA) between the nodes, the position of the tag is estimated by Direct Method (DM) using hyperbolic navigation. The accuracy of the position estimate is improved by an iterative Davidon-Fletcher-Powell (DFP) algorithm. The Mean Square Error (MSE) between the true position of the tag and its estimate are obtained. The implementation of the proposed scheme was undertaken at BEL, CRL, Bangalore using the impulse radio UWB transceiver system. The MSE value is minimal when the reference nodes are closer to each other and to the moving target. The precision of the position location estimation can be improved by increasing the densities of the reference nodes. Wavelet Denoising (WD) is applied in time delay estimation between two spatially separated nodes in the presence of noise. The UWB signal transmitted by the tag to neighbouring nodes is a sine wave burst signal instead of a Gaussian process which hinders their usage in several practical applications. It is shown that generation of UWB pulses as wavelet are simpler and they also comply with the Federal Communications Commission (FCC) regulations better than a Gaussian process.