A Novel Algorithm for Simple Hybrid of Adaptive Array and Equalizer

Abstract

Adaptive array has been used for canceling the interference in communication. When the array cannot suppress all the interference, an equalizer following the array can add to further enhance the capability of canceling the inter-symbol interference (ISI). The adaptive array and equalizer (AE) will suffer the problems of insufficient degrees of freedom and main-beam multi-path ISI. The hybrid of adaptive array and equalizer (HAE) uses a modified training sequence to adjust the weights of adaptive array that leads the array to cancel only the co-channel interference (CCI). The ISI are removed by the equalizer following the array. Thus, the HAE can combat the above problems successfully. Though the HAE improves the performance of AE, a transversal filter is added to generate the modified training sequence. Besides, the weights of equalizer in the HAE, which adjust after the weights of adaptive array, will make the convergent rate slowly. A simple hybrid of adaptive array and equalizer (SHAE) utilizes the output signal of system to adjust the weights of both the adaptive array and equalizer simultaneously. Therefore, the convergent rate of the HAE can improve by the SHAE. Moreover, the ISI can be suppressed by the equalizer instead of the adaptive array in the SHAE that will improve the performance of AE without using the transversal filter. As the mutual coupling present, the convergent rate of the SHAE will slow down. In this paper, a least mean square error algorithm with mutual coupling present is proposed to improve the convergent rate of SHAE, also.