摘要: |
为进一步改进盲均衡算法收敛速度慢、稳态误差大、计算复杂度高等问题,提出一种切换模式和加权模式联合CMA(Constant Modulus Algorithm)+DDLMS(Direct Decision Least Mean Square)双模式盲均衡算法。综合切换双模式盲均衡算法和加权双模式盲均衡算法的优缺点,对切换、加权模式联合的CMA+DDLMS双模式盲均衡算法进行仿真。在不同信噪比条件下,对CMA算法、MCMA(Modified CMA)算法、DDLMS算法和CMA+DDLMS双模式盲均衡算法进行仿真,结果表明,所提算法收敛速度快,约为600个符号;稳态误差小,约为0.1;误码率小,在信噪比为25 dB时,误码率约为10-6。该算法可广泛应用于无线通信、光通信、声呐和雷达等众多领域。 |
关键词: 卫星通信 信道均衡 CMA+DDLMS盲均衡 切换模式 加权模式 |
DOI: |
|
基金项目:中国科学院战略性先导科技专项(A类)(XDA15350103) |
|
A Dual-mode Blind Equalization Algorithm Based on CMA and DDLMS Algorithm |
HU Wanru,MEI Ruru,CUI Jian,WANG Zhugang |
(1.National Space Science Center,Chinese Academy of Sciences,Beijing 100190,China;2.University of Chinese Academy of Sciences,Beijing 100049,China;3.School of Information,North China University of Technology,Beijing 100144,China) |
Abstract: |
In order to solve the problem of slow convergence speed,large steady-state error and high computational complexity of blind equalization algorithm,the constant modulus algorithm(CMA)+direct decision least mean square(DDLMS) dual-mode blind equalization algorithm combining switching mode and weighted mode is proposed.By combining the advantages and disadvantages of the switching dual-mode blind equalization algorithm and the weighted dual-mode blind equalization algorithm,the CMA+DDLMS dual-mode blind equalization algorithm combining switching mode and weighted mode is simulated.Under different signal-to-noise ratio(SNR) conditions,the CMA blind equalization algorithm,MCMA blind equalization algorithm,DDLMS blind equalization algorithm and CMA+DDLMS dual-mode blind equalization algorithm are simulated,and the results show that,the convergence speed of the algorithm is fast,about 600 symbols;the steady-state error is small,about 0.1;and the symbol error rate is small,about 10-6 when the SNR is 25 dB.The algorithm can be widely used in wireless communication,optical communication,sonar,radar and many other fields. |
Key words: satellite communication channel equalization CMA+DDLMS blind equalization switching mode weighted mode |