TH-BPSK与TH-PPM超宽带系统性能分析及比较

Performance Analysis and Comparison of Ultra Wideband TH-BPSK and TH-PPM Systems

对于使用窄脉冲传输数据的超宽带系统,从理论上分析了在TH-BPSK和TH-PPM两种调制方式下系统的信干噪比,从概率角度详细估计了系统噪声的影响。然后对两种调制方式下系统的性能进行了比较,在单用户情形下得到TH-BPSK系统性能恒比TH-PPM好的结论;在考虑系统噪声的多用户情形下给出了一个判决量的计算公式,该判决量仅由基本接收脉冲波形和用户数决定,根据判决量的值可以判断是TH-PPM系统性能好还是TH-BPSK系统性能好。文中给出了应用高斯各阶导数作接收脉冲时系统的信干噪比随用户数的变化情况。结果表明用高斯函数的各阶导数作接收脉冲时,TH-BPSK系统性能比TH-PPM系统性能好。

In this paper we analyze the SINR （Signal to Interference and Noise Ratio） of UWB systems, which transmit data information using short pulses with different modulation schemes： TH-BPSK and TH-PPM. From the perspective of probability, the effect of the system noise is estimated in detail. A comparison between the two kinds of UWB systems is carried out and the result shows that the performance of TH-BPSK always exceeds that of TH-PPM in the single-user system; In the multi-user system, when the receiver noise is considered, a decision variable that is completely determined by the received pulse shape and the number of the users is defined to evaluate the performance of these two UWB systems. When the received pulse is derivations of Gauss function, the performance of TH-BPSK is better than that of TH-PPM system.