The capacity of M-ary PPM ultra-wideband communications over multipath channels

The capacity of M-ary PPM ultra-wideband communications over multipath channels is analyzed in this paper. And the closed form of the output signal-to-noise ratio (SNR) of the receiver is derived. In addition, the link budget is taken into account incorporate to the specific constraints, which are mainly the power spectrum density limitation under FCC part 15 rules. Finally, the influence of muitipath number on the capacity of M-ary PPM ultra-wideband communications is analyzed and compared to the user number. It is shown that the capacity of M-ary PPM ultra-wideband communications over multipath channels is decreased faster with the increasement of the multipath number than that with the increasement of the user number.