Direct sequence modified time hopping PPM over ultra wideband S-V channel

A three position Pulse Position Modulation (PPM) scheme is proposed for a Direct Sequence Time Hopping Ultra Wideband wireless communication system. The channel is based on the Saleh-Valenzuela model. We show that by adapting the Space Time Spreading technique to use three pulse positions in a single input single output system representing -2,0,2 an improvement in Bit Error Rate is achieved compared to sending the same bits using two pulse positions only. In addition, the bit access rate is doubled as two bits can be successfully sent in the same time using our proposed system.