改进的可见光通信系统PTS峰均比抑制方法

Improved PTS peak-to-average ratio suppression method in visiblelight communication system

针对非对称剪切正交频分复用(asymmetric-clipped orthogonal frequency division multiplexing,ACO-OFDM)可见光通信(visible light communication,VLC)系统中信号的高峰均功率比(peak-to-average power ratio,PAPR)问题,采用部分传输序列(partial transmit sequence,PTS)方法,并结合二进制离散粒子群优化(discrete particle swarm optimization,DPSO)算法,提出一种改进的PTS峰均比抑制方法——DPSO-PTS方法。利用DPSO算法对加权的相位因子进行优化处理,选择最佳的相位因子组合来有效控制PAPR的范围,并对乘加权信息的子块进行求和,从而选择出最小PAPR对应的一组信号进行传输。仿真结果表明,在互补累计分布函数(complementary cumulative distribution function,CCDF)为10-4时,DPSO-PTS方法的系统PAPR降低了约4 dB,且相较于传统PTS方法,系统的复杂度和误码率(bit error rate,BER)性能也得到有效的改善。

In order to solve the peak-to-power ratio(PAPR)problem in asymmetric shear orthogonal frequency division multiplexing(ACO-OFDM)visible light communication(VLC)systems,using the idea of partial transmit sequence(PTS)method,and combining the discrete particle swarm optimization(DPSO)algorithm,an improved PTS peak-to-average ratio suppression method—DPSO-PTS method is proposed.The DPSO algorithm is used to optimize the weighted phase factors,select the best combination of phase factors to effectively control the range of PAPR,and sum the subblocks of multiplicative weighted information,so as to select a group of signals corresponding to the minimum PAPR for transmission.The simulation results show that when the complementary cumulative distribution function(CCDF)is 10-4,the PAPR of DPSO-PTS method is reduced by about 4 dB,and the complexity and bit error rate(BER)performance of DPSO-PTS method are also improved effectively compared with the traditional PTS method.