基于似然估计修正信噪比的编码调制切换算法

CODE MODULATION SWITCHING ALGORITHM BASED ON LIKELIHOOD ESTIMATION MODIFIED SIGNAL-TO-NOISE RATIO

AOS通信系统在进行编码调制切换时,由于信道环境和信道衰落的影响,传统的编码调制切换算法难以解决高阶的调制编码方式的高传输效率和低阶的调制编码方式的可靠性的矛盾。提出一种基于似然估计修正信噪比的编码调制切换算法,该方法在方差修正平均信噪比的基础上,根据信道的概率特性,考虑时变衰落信道对传输数据的影响,结合最大似然估计算法和长短期记忆网络来选取参考信噪比和预测信道状态,使系统在提升传输效率的同时保证可靠性。仿真结果表明,与基于方差修正信噪比的编码调制切换算法、基于经验方差修正信噪比的编码调制切换算法相比,该算法能有效提升系统的传输效率和吞吐量,降低系统的误码率。

In the code modulation switch of AOS communication system,due to the influence of channel environment and channel fading,the traditional code modulation switching algorithm is difficult to solve the contradiction between the high transmission efficiency of high-order modulation coding method and the reliability of low-order modulation coding method.This paper proposes a code modulation switching algorithm based on likelihood estimation modified signal-to-noise ratio(SNR).Based on the variance modified average SNR,considering the influence of time-varying fading channel on transmission data,according to the probability characteristics of the channel,and combining the maximum likelihood estimation algorithm and long short-term memory network,this algorithm selected the reference SNR and predicted the channel state.It improved the transmission efficiency and ensured the reliability at the same time.The simulation results show that the proposed algorithm can effectively improve the transmission efficiency and throughput of the system,and reduce the bit error rate of the system,compared with the code modulation switching algorithm based on variance modified SNR and empirical variance modified SNR.