Abstract: On the basis of the research and analysis of T/4 fractionally spaced equalizer based on constant modulus algorithm（T/4-FSE-CMA）, for non-constant modulous QAM signals, a T/4 Fractionally Spaced blind Equalization algorithm based on Cosine Cost Function（T/4-FSE-CCF） is proposed. The cost function of CMA is replaced by cosine cost function in the proposed algorithm. The new algorithm gets rid of the dependence on statistical Modulus value [R] compared with CMA, and when the equalizer is ideal balanced, the steady-state Mean Square Error（MSE） of the algorithm is zero. The performance of the proposed T/4-FSE-CCF is simulated by [M] file of MATLAB. After the optimum performance parameters of proposed T/4-FSE-CCF are obtained, the Simulink model of the T/4-FSE-CCF can be established.

Key words: constant modulous algorithm, fractionally-spaced, cosine cost function, error function, Simulink

摘要： 在对T/4-FSE-CMA算法研究分析的基础上，针对非常模QAM信号，提出了一种基于余弦代价函数T/4分数间隔盲均衡算法（T/4-FSE-CCF）。该算法将CMA的代价函数用构造的余弦代价函数来替代；新算法摆脱了CMA对统计模值[R]的依赖，且均衡器理想均衡时该算法的的稳态均方误差（Mean Square Error，MSE）为零。通过MAT-LAB的[M]文件对T/4-FSE-CCF的性能进行验证，在获得算法最佳性能时的参数值后，进一步由这些参数搭建了T/4-FSE-CCF的Simulink仿真模型。

关键词: 常模算法, 分数间隔, 余弦代价函数, 误差函数, Simulink