The BER performance optimization of ultra wideband TH-PPM in a multi-path environment

Abstract

This paper is focuses on the unbalanced bit error rate (BER) for different transmitted data symbols of ultra wideband (UWB) impulse radio time-hopping pulse-position-modulation (TH-PPM) in a deterministic multi-path environment for unreasonable parameter selection. Two solutions are presented here. The first is that the decision threshold of RAKE is dynamic for different channel environments; the other is that we can improve the traditional TH-PPM modulation, which is, encoding the transmitted data symbol with balance code. It is shown by theoretical analysis and computer simulation that these two methods can solve the unbalanced BER of traditional TH-PPM. Compared with the dynamic threshold method, the balance encoding scheme can be implemented more easily, and is more robust to the channel time variant characteristics, the channel estimation of RAKE receiver and the combination techniques.