为了研究Polar码在编码调制(CM)系统中的性能,提出了一种基于Polar码的比特交织编码调制(BICM)系统.分析了高斯白噪声(AWGN)信道中不同调制方式对系统误比特率(BER)性能的影响,并将所提系统的BER性能与基于低密度奇偶校验(LDPC)码的BICM系统性能进行了对比.仿真结果表明,在QPSK调制下,基于Polar码的BICM系统与基于Polar码的无编码调制系统的BER曲线几乎完全重合;而在16QAM调制下,当码长较大时,基于Polar码的BICM系统较基于Polar码的无编码调制系统最大节省0.8 d B的比特信噪比.当信道编码码长为1 024、码率为0.5时,在中高比特信噪比区域上,基于Polar码的BICM系统可比基于LDPC码的BICM系统获得至少2 d B的比特信噪比增益.
In order to study the performance of the Polar code in coded modulation( CM) systems,a bit interleaved coded modulation( BICM) scheme based on the Polar code is proposed. The influences of different modulations on system bit error rate( BER) performance in additive white Gaussian noise( AWGN) channel are analyzed. The BER performance of the proposed system is compared with that of the BICMsystem based on the lowdensity parity check( LDPC) code. The simulation results showthat,in quadrature phase shift keying( QPSK) modulation,the BER curve of the BICMsystem based on the Polar code is almost in complete coincidence with that of the system exempted from CMtechnique based on the Polar code. However,the former system can obtain 0. 8 d B bit signal to noise ratio gain at most in 16-quadrature amplitude modulation( 16QAM) when the code length is larger. When the channel code length is 1 024 and the code rate is 0. 5,in medium and high bit signal to noise ratio regions,the BICMsystem based on the Polar code can achieve at least 2 d B bit signal to noise ratio gain compared with the BICMsystem based on the LDPC code.