On the Performance of UWB-IR With Interleaved Coding Modulation and Polarity Randomization on AWGN and Multipath Fading Channels

One of the main challenges in designing high-data-rate ultrawideband impulse radio (UWB-IR) systems is their sensitivity to intersymbol and interpulse interferences, which may significantly degrade the performance. This paper deals with new methods of protection against errors for UWB-IR systems operating in severe multipath interference-prone environments. The proposed and investigated techniques include interleaved coding modulation and polarity randomization applied in combination with superorthogonal convolutional coding or frame repetition. The performance of high-data-rate (125 Mb/s) coded UWB-IR systems is evaluated on the additive white Gaussian noise and realistic UWB channels that have recently been proposed by the IEEE. Our UWB-IR system incorporates a differential autocorrelation receiver, allowing for a simple hardware architecture. Through theoretical analysis of the bit error rate (BER) and the use of Monte Carlo simulations, we demonstrate that the application of the proposed methods may lead to significant performance improvements.