Performance Analysis of Time-Hopping Pulse Width Modulation for Ultra-Wideband Impulse Radio

The ultra wide-band (UWB) technology is going to become one of main technologies in short-range high-rate wireless communications due to its unique characteristics. This paper presents a new modulation scheme-pulse width modulation (PWM) for UWB communication systems and describes the signal model modulated by this modulation scheme based on the time-hopping (TH) multiple access mode. Its bit error rate (BER) performance is analyzed in presence of multipath channel and a comparison is made between TH-PWM and time-hopping pulse position (TH-PPM) systems. BER performances for these two systems are simulated respectively in the four typical dense multipath channel CM1-CM4 recommended by IEEE 802.15.3a. The theoretical and simulation results prove that PWM is a viable modulation scheme with better BER performance for UWB communication systems. Despite the theoretical analysis and simulation are based on the time-hopping multiple access, PWM modulation scheme can also be applied to other multiple access methods of UWB communication system.