To boost the performance of 4-ary pulse amplitude modulated(PAM) at low signal-to-noise ratio(SNR), bistable stochastic resonance(BSR) system is introduced into digital communications system and get a reliable signal ...To boost the performance of 4-ary pulse amplitude modulated(PAM) at low signal-to-noise ratio(SNR), bistable stochastic resonance(BSR) system is introduced into digital communications system and get a reliable signal detection scheme. In this paper, we first analyse BSR system for different amplitudes of 4-ary PAM signals. The steadystate of the bistable system will be statistically distinct, and the feasibility of the proposed detection scheme is confirmed. On this basis, we present a detailed study on steady-state transitions of the BSR system, and an explicit expression of the bistable system parameters is derived. By setting the bistable system parameters, bistable system, 4-ary PAM signal, and noise reach the resonance state, and the BSR-based detection scheme is implemented. Moreover, we derive an analytical expression to calculate the symbol error rate(SER) of 4-ary PAM signals with the BSR-based detection under additive white Gaussian noise(AWGN). Finally, the simulation results validate that BSR-based detection scheme can improve the detection performance while efficiently reducing the symbol error rate.展开更多
由于传统的LDPC码位翻转解码算法在计算复杂度方面无法得到提高等缺点,为降低传统非二进制低密度奇偶校验码解码算法的复杂度和误码率,提出一种改进的基于NB-LDPC解码算法。对现有的并行符号翻转解码算法(parallel symbol flipping deco...由于传统的LDPC码位翻转解码算法在计算复杂度方面无法得到提高等缺点,为降低传统非二进制低密度奇偶校验码解码算法的复杂度和误码率,提出一种改进的基于NB-LDPC解码算法。对现有的并行符号翻转解码算法(parallel symbol flipping decoding algorithm,PSFD)进行优化改进,采用多次投票方法,使每个不满意的校验节点对相应的变量节点进行多次投票,并结合误差估计方法。考虑到额外的复杂性,两级投票是提出优化算法的最佳选择。大量实验结果表明,相比原有的LDPC码位翻转解码算法,该优化算法避免使用码相关的投票阈值,在BER等于10-5时,误码率低约0.4dB,在中低数值的SNR上,具有最优参数的优化算法比原有算法收敛得更快。展开更多
基金supported by the National Natural Science Foundation of China (61631015, 61501354, 61501356, and 61573202)the Fundamental Research Funds of the Ministry of Education (7215433803)+5 种基金the Foundation of State Key Laboratory of Integrated Services Networks (ISN1101002)Higher School Subject Innovation Engineering Plan (B08038)Science and Technology Innovation Team Key Plan of Shaanxi Province (2016KCT-01)The Fundamental Research Funds of the Ministry of Education, China (Grant No. JB160101)The Key Laboratory Foundation of Ministry of Industry and Information Technology (KF20181912)China Postdoctoral Science Foundation (2018M631122)
文摘To boost the performance of 4-ary pulse amplitude modulated(PAM) at low signal-to-noise ratio(SNR), bistable stochastic resonance(BSR) system is introduced into digital communications system and get a reliable signal detection scheme. In this paper, we first analyse BSR system for different amplitudes of 4-ary PAM signals. The steadystate of the bistable system will be statistically distinct, and the feasibility of the proposed detection scheme is confirmed. On this basis, we present a detailed study on steady-state transitions of the BSR system, and an explicit expression of the bistable system parameters is derived. By setting the bistable system parameters, bistable system, 4-ary PAM signal, and noise reach the resonance state, and the BSR-based detection scheme is implemented. Moreover, we derive an analytical expression to calculate the symbol error rate(SER) of 4-ary PAM signals with the BSR-based detection under additive white Gaussian noise(AWGN). Finally, the simulation results validate that BSR-based detection scheme can improve the detection performance while efficiently reducing the symbol error rate.
文摘由于传统的LDPC码位翻转解码算法在计算复杂度方面无法得到提高等缺点,为降低传统非二进制低密度奇偶校验码解码算法的复杂度和误码率,提出一种改进的基于NB-LDPC解码算法。对现有的并行符号翻转解码算法(parallel symbol flipping decoding algorithm,PSFD)进行优化改进,采用多次投票方法,使每个不满意的校验节点对相应的变量节点进行多次投票,并结合误差估计方法。考虑到额外的复杂性,两级投票是提出优化算法的最佳选择。大量实验结果表明,相比原有的LDPC码位翻转解码算法,该优化算法避免使用码相关的投票阈值,在BER等于10-5时,误码率低约0.4dB,在中低数值的SNR上,具有最优参数的优化算法比原有算法收敛得更快。