An energy efficient transmitted-reference scheme for ultra wideband communications

Transmitted-reference (TR) receivers represent a low complexity alternative to RAKE receivers, which are widely used in ultra wideband (UWB) communications. Known TR schemes are not very energy efficient, since two pulses represent one bit value only. Therefore, we present a TR pulse interval amplitude modulation (PIAM) scheme which reduces the required energy per bit and a low complexity receiver structure for TR PIAM. We investigate the performance of TR 4PIAM analytically and by means of simulation and show that higher modulation alphabets can be adapted easily. Moreover, we show that there exists an optimal correlation length for transmission over multipath channels.