Multi-user capacity of M-PPM UWB system using PSWF pulses

The information capacity model of M-ary PPM ultra-wideband communications is built over multiple-access and additive white Gaussian noise channel. The model extends the known capacity of PPM orthogonal pulses to incorporate specific UWB constraints. Based on Gaussian approximation for the multiple access interference, an expression of the UWB capacity is developed as a function of system parameter. The channel capacity of UWB communications using PSWF pulses subject to FCC spectral masks is computed, and the results is compared with that of 5^th and 7^th order Gauss pulse. The simulation results show that the UWB system with the PSWF pulses has more channel capacity than the system with Gaussian pulse. This conclusion presents a new view for the UWB pulse choice, which can facilitate system designers to improve the efficiency of UWB communications.