OFDM系统中相干解调M-PSK的导引符号功率优化

在多径衰落信道下,分析了采用M-PSK的相干解调正交频分复用系统中导引符号功率对解调性能的影响,优化了导引符号与数据符号功率比,计算了不精确信道估计引起的系统性能的损失。分析和仿真结果表明,最优导引符号功率与数据符号功率之比由信噪比、多普勒频率和内插滤波器系数等因素决定。当采用最优功率比值时,为达到相同的误比特率,所需的总发射功率最小。

Analysis and Optimization of Pilot-Symbol-Assisted M-PSK for OFDM Systems

The current analysis focuses on the influence of demodulation performance in multipath fading propagation environments, which results from the pilot power variation of pilot symbol assisted modulation M-PSK in orthogonal frequency division multiplexing systems. The pilot-to-data power ratio is optimized analytically, and the loss due to imperfect channel estimation is calculated. Theoretical and simulation results show that the optimum pilot-to-data power ratio is affected by the signal-to-noise ratio, Doppler frequency and interpolation size etc. Once the optimization parameter of pilot-to-data power ratio is used, system transmission power is minimum while still meeting the fixed bit error rate target.