基于正交MFSK信号的解调优化算法  

Optimization Analysis of Demodulation Based on Quadrature MFSK Signal

作　　者：李濛 吴呈瑜 占敖 LI Meng;WU Chengyu;ZHAN Ao(School of Information and Technology,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]浙江理工大学信息学院,杭州浙江310018

出　　处：《无线电通信技术》2022年第3期541-546,共6页Radio Communications Technology

基　　金：国家自然科学基金(61801430);浙江理工大学基本科研业务费专项资金资助(2021Q029)。

摘　　要：针对传统多进制频移信号解调算法存在计算量大、误码率高等问题,提出了一种基于正交多进制频移键控(Multiple Frequency Shift Keying,MFSK)信号的解调算法。该算法通过检测和判决MFSK信号在不同频率点处的功率谱峰值来完成信号同步,然后对信号的同向分量和正交分量进行反正切运算求得信号斜率,再根据信号斜率构建差值序列并建立MFSK信号解调数学模型,最后通过模型求解完成信号的调制进制识别和解调。该算法复杂度较低且仅呈线性增长,仿真结果表明该算法在性能上优于传统的小波解调算法,且当输入信噪比大于6 dB时,对2FSK、4FSK、8FSK和16FSK的解调正确率都可以达到90%以上。Aiming at the problems of high computational complexity and high bit error rate in traditional multi-system frequency-shifted signal demodulation algorithm,a demodulation algorithm based on quadrature MFSK(Multiple Frequency Shift Keying)signal is proposed.The algorithm completes signal synchronization by detecting and judging power spectrum peaks of the MFSK signal at different frequency points,and then performs arc tangent operation on the in-direction and quadrature components of the signal to obtain signal slope,constructs the difference sequence according to the signal slope.Next it establish the mathematical model of MFSK signal demodulation,and finally complete signal modulation system identification and demodulation through model solution.The complexity of the algorithm is low and only increases linearly.Simulation results show that the algorithm is superior to the traditional wavelet demodulation algorithm in performance,and when the input signal-to-noise ratio is greater than 6 dB,the demodulation accuracy of 2FSK,4FSK,8FSK and 16FSK can reach more than 90%.

关 键 词：MFSK 信号解调 误码性能 位同步 

分 类 号：TP92[自动化与计算机技术]