Enhancement of Matched filter BER performance in DS-UWB systems using a new channel estimation technique

ElDin, Mohamed Salah; Zahra, M. M.; Abdel Fattah, Shawky

doi:10.21608/mjeer.2011.66819

Enhancement of Matched filter BER performance in DS-UWB systems using a new channel estimation technique

Document Type : Original Article

Authors

¹ Dept. of Communications Eng., Higher Institute of Engineering, Al Shorouk Academy

² Dept. of Electrical Engineering, Faculty of Engineering, Al Azhar University

10.21608/mjeer.2011.66819

Abstract

One of the major challenges in ultra wideband (UWB) receivers is to recover the signal energy dispersed over too many multi path components, while preserving the receiver complexity as low as possible. To this achieve this, channel estimators based receivers are employed to enhance its Bit Error Rate (BER) performance. In this paper the problem of channel estimation for Direct Sequence ultra wideband (DS UWB) is investigated. Firstly, a modification of the received signal model is introduced. A new channel estimation algorithm is proposed .The proposed algorithm is cost effective, very simple and is independent of the number of paths of the UWB channel. Monte-Carlo simulation is used to calculate the Mean Square Error (MSE) of the proposed estimator by averaging the estimation error of a 1000 generated channel realizations for each of the four different IEEE 802.15.3a UWB channel models. The Mean Squared Error (MSE) of the proposed estimator is compared with that of the time domain Maximum Likelihood (ML) estimator. Simulation results show that The MSE performance of the proposed estimator is competitive to that of the ML even in the case of non perfect orthogonal spreading codes and approaches the behavior of the ML as the length of the spreading code increases.

Keywords

References

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