Research on Wavelet Transform Blind Equalizer Based on Different Place
Yingge Han, Baokun Li, Lin Zhang · 2015
In order to improve the convergence speed of adaptive equalizer, orthogonal wavelet transform has been introduced into adaptive equalizer.The orthogonal wavelet transform are placed in the front of the equalizer (forward filter) in the existing literature, which will reduce the performance of equalizer.In order to study the equalizer performance under the different placement of wavelet transform, based on the Constant Modulus Algorithm Decision Feedback Equalizer (CMA-DFE) as an example, the forward balance orthogonal multi-wavelet transform based CMA-DFE (MWT-CMA-DFE), the feedback balance orthogonal multi-wavelet transform based CMA-DFE(FMWT-CMA-DFE) and the dual balance orthogonal multi-wavelet transform based CMA-DFE (DMWT-CMA-DFE) are proposed and analyzed respectively.Moreover, the complexities of the proposed equalizers are analyzed.Simulation tests with underwater acoustic channel have indicated that the DMWT-CAM-DFE not only has the faster the performances of convergence and tracking the time vary channel but also can eliminate phase rotation compared with CMA-DFE, MWT-CMA-DFE and FMWT-CMA-DFE.