On the multiple-access capability of the bi-phase modulated TH-CDMA impulse radio networks

This paper is concerned with error rate performance analysis of ultra-wide bandwidth (UWB) time-hopping multiple access radio networks employing bi-phase pulse modulation (TH-CDMA/BPM). Under the assumption of rectangular pulses, we derive an exact expression for the multiple access interference. This leads to a new expression for the bit error probability of a TH-CDMA/BPM communication link subjected to other K interfering signals. Our numerical results suggest that an impulse radio network employing bi-phase modulation can support more users than an equivalent system employing pulse position modulation.