Achievable rates of transmitted-reference ultra-wideband radio with PPM

In this letter, we study the achievable rates of practical ultra-wideband (UWB) systems using pulse position modulation (PPM) and transmitted-reference (TR) transceivers. TR obviates the need for complex channel estimation, which is particularly challenging in the context of UWB communications. Based on an upper bound we derive for the error probability with random coding, we establish that for signal-to-noise ratio values of practical interest, PPM-UWB with TR can achieve rates on the order of C(/spl infin/)=P/N/sub 0/ (nats/s), where C(/spl infin/) denotes the capacity of an additive white Gaussian noise channel in the UWB regime for average received power P and noise power spectrum density N/sub 0/.