脉冲位置键控系统误比特性能分析

梳理基于等待门限判决的脉冲位置键控系统相关文献资料，发现文献给出的误比特率(BER)理论公式不能准确描述系统误比特率，尤其是在低信噪比情况下一些理论公式计算的误比特率已经高于0.5，超过了通信系统误比特率上限，不符合通信理论。分析了各文献资料误比特率理论公式推导过程中的问题所在，推导得到了一个新的误比特率理论公式。进行了数值仿真，结果表明，新的误比特率理论公式与仿真吻合良好，能够准确描述系统误比特率，并且在低噪比下计算的误比特率不高于0.5，符合通信理论。在新的误比特率理论公式基础上，分析了基于等待门限判决的脉冲位置键控系统能量效率，并与二进制相移键控(BPSK)系统进行了比较，表明基于等待门限判决的脉冲位置键控系统是一种具有较高能量效率的系统，在一定条件下甚至优于BPSK系统。

BER performance analysis of pulse position keying system

From the literature of the threshold type decision pulse position keying system, it is found that the theoretical formula given by the literature cannot describe the Bit Error Rate(BER) accurately. Especially under low signal to noise ratio, the BER calculated by the theoretical formula is bigger than 0.5, which is in inconformity with communication theory. The problems of the literature in deducing the formula are analyzed and a new theoretical formula is given for the BER of the threshold type decision pulse position keying system. Simulation results show that the new theoretical formula can describe the BER accurately, and the BER calculated by the theoretical formula is below 0.5 under low signal to noise ratio, which is in conformity with communication theory. Based on the new theoretical formula, the energy efficiency of the threshold type decision pulse position keying system is analyzed and compared with that of Binary Phase Shift Keying(BPSK) system. The results show that the threshold type decision pulse position keying system is energy efficient and even better than BPSK system in some situations.