Error Rate of DS-IR with RAKE Reception in Frequency Selective Channels

Direct sequence impulse radio (DS-IR) is a flexible ultra wideband (UWB) format that jointly exploits direct sequence (DS) and time hopping (TH) spreading. The symbol error rate (SER) of DS-IR is analysed for a QPSK system transmitting over a frequency selective channel with coherent RAKE reception. The inter symbol interference (ISI) and other impairments affecting the system are studied and novel SER estimation methods are introduced. The methods are used to assess the performance over a realistic channel model and to analyse the effect of the system parameters. It is shown that, thanks to the TH, the system duty cycle can be varied with a minor impact on the SER.