Performance And Capacity Analysis Of DPPM UWB Over Fading Channels

The radiation spectrum of Ultra-wide band (UWB) wireless communication system is mainly decided by the pulse waveforms and modulation methods of the signal. There are many kinds of pulse waveforms which can be selected for UWB systems according to the needs of the radiation spectrum. And the modulation methods that UWB often uses are On-Off Keying (OOK), Pulse Amplitude Modulation (PAM), Phase Shift Keying (PSK), Pulse Position Modulation (PPM) and so on.The purpose of this paper is that through analyzing the new modulation scheme- Differential Pulse-Position Modulation (DPPM) to seek out the methods which can improve the capacity and performance of UWB system.At the beginning of this paper, it reviews and looks forward to the development of UWB wireless communication technologies. Then, it simply displays the application results of UWB and summarizes some key technical of UWB wireless communication systems. At the central part, it mainly studies and analyzes the DPPM technology. DPPM, as a new emerging modulation scheme, which is a simple improvement of PPM, achieves higher power efficiency, bandwidth efficiency, performance and channel capacity than PPM. Therefore, the analysis of DPPM is very useful for improving the performance of UWB systems. In addition, experience has proved that,the system performance is differential between in the laboratory additional white gaussian noise (AWGN) environment and in the actual transport environment. And, Nakagami-m fading model can be used in modeling the actual transmission channel of UWB systems, so it focus on analyzing the performance of DPPM under Nakagami-m fading channels. In this section, it first gives the DPPM signal and Nakagami-m fading channels model. Then, it gives the formulas which apply to calculate the error probability and capacity of a UWB system with DPPM over AWGN and Nakagami-m fading channels. At last, it analyzes the relationship between the capacity and the signal to noise ratio (SNR), the error probability and SNR by Monte Carlo simulation respectively. These results will provide a theoretical basis for data transfer rates designed of UWB wireless communication systems.