UWB localization techniques for precision automobile parking system

Ultra-wideband (UWB) communication system provides high accurate localization due to the high multi-path resolution capacity. For ultra-wideband (UWB) 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) 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 the appropriate UWB localization technique for the precision automobile parking system. 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 UWB impulse radio for precision localization. In this paper an overview of the schemes that can be adopted for the implementation of the proposed system for precision automobile parking application is presented. The generation of UWB pulses as a Gaussian process and in the form of wavelets are considered and compared. Techniques like generalized cross correlation (GCC), wavelet denoising (WD) as applied for time delay estimation is discussed. The methods like hyperbolic navigation or direct method (DM) and an iterative Davidon-Fletcher-Powell (DFP) algorithm is utilized for position estimation and the results are compared. It is shown that generation of UWB pulses as wavelet is simpler and they also comply with the FCC regulations better than a Gaussian process. The DFP algorithm gives improved precision due to its iterative nature when compared with the DM when they are utilized for position estimation of the target.