Delay hopping and chip codes design for a frame differential uwb autocorrelation receiver

The performance of a conventional threshold detector for a frame differential autocorrelation receiver in IR UWB systems in a dense multipath channel are improved by means of appropriate chip code and delay hopping code design. We point out which conditions must be satisfied by the delay hopping code in order to reduce the nonlinear ISI and the bias term, which are peculiar nuisance parameters of autocorrelation receivers. Moreover, by extending the periodicity of the chip code, we show how to suppress linear ISI. Simulated results confirm the performance improvement in terms of BER. An analytical expression relating the noise power to the system parameters is also presented. These results can be extended to the well known transmitted reference systems.