This paper presents a new transmission scheme of M-ary biorthogonal pulse position modulation (BPPM) in ultra wideband systems. The proposed scheme incorporates position-wise parity information to improve the probability of symbol detection over multipath channels. A linear filter-based channel modification is also introduced to mitigate multipath degradation and maximize the probability of symbol detection by using parity information. The analytical and numerical results show that the proposed scheme achieves a significant improvement of symbol error rate (SER) with very low computational complexity and no symbol delay.

A new receiver structure that combines the constant modulus algorithm (CMA) and the Kalman filter (KF) is investigated to exploit the advantages of both algorithms; simple implementation of blind algorithms, and excellent tracking ability, respectively. The proposed scheme achieves faster convergence and adaptability to the channel variation, which is verified through comparative simulations in doubly-selective (time- and frequency-selective) fading channels.