UWB impulse radio signals have a very short duration, extremely wide bandwidth and share the same frequency spectrum with other existing systems. It was determined by the Federal Communications Commission (FCC) that UWB systems could cause interference with other systems, such as Global Positioning System (GPS) for example. Therefore, at present, the FCC has restricted the use of UWB systems to frequencies above 3.1 GHz. In this paper, we evaluated performance of UWB system using proposed pulses that are strictly limited in time to remove interference while, at the same time, contain their power distribution to a frequency band from 3.1 GHz to 10.6 GHz. In particular, we evaluated the BER Performance in relation to system parameters such as pulse duration, δ, the number of users, Nu, and the number of symbols, M. We found the optimal pulse duration δ through computer simulation using developed UWB pulses. It is shown that performance evaluation between the UWB communication system using these UWB pulses and the Gaussian monocycle pulse in M-ary PPM and BPSK schemes. These results can be contributed to construct M-ary PPM UWB communication system in terms of multiuser parameters and pulse duration.