基于部分采样点辅助校正OFDM信号的准无损压缩算法

Nearly Loss-Less Compression Algorithm Based on Partial Sample Points Calibration for OFDM Signal

传统的正交频分复用(Orthogonal frequency division multiplexing,OFDM)信号压缩算法由于低的压缩比和低的信号量化误差比(Signal to quantization-error ratio,SQR)造成较高的误码率,无法满足OFDM系统的需求。为了实现高的压缩比和低的误码率,提出了一种联合削峰尾插(Clipping with tail plug,CTP)技术、几何级数压扩(Geometric series companding,GSC)技术及部分采样点校正(Partial sample calibration,PSC)技术的准无损压缩算法。计算机仿真结果表明,对于4096-正交幅度调制(Quadrature amplitude modulation,QAM)的OFDM信号,压缩比最高可达1.86∶1,误码率低于10-7,量化误差对应的平均SQR高达70dB,因而能够很好地满足光纤到分配点+千兆数字用户线路(Fiber to the distribution point+GCga digital subscriber line,FTTdp+GDSL)系统的需求。

Traditional compression algorithms of OFDM signals with low compression ratio and signal to quantization-error ratio（SQR） come along with a high error rate, which fail to meet the requirements of OFDM systems. To achieve the high compression ratio and the low error rate, a new algorithm is pro- posed based on a combination of clipping with tail plug （CTP）, geometric series companding （GSC） and partial sample calibration （PSC）. The new algorithm can achieve the nearly loss-less compression and the compression ratio can be as high as 1.86 ： 1 with a error rate less than 10-7 , while SQR corresponding to the quantization error is 70 dB in 4096-QAM OFDM signal modulation schemes meeting the requirements of the FTTdpq-GDSL systems well.