Semi blind equalization techniques are popular adaptive techniques used in digital communications. This project is divided into two subparts. First subpart includes the introduction to the Euclidean Direction Search (EDS) algorithm which has both advantages of Least Mean Square (LMS) algorithm and Recursive Least Square (RLS) algorithm, and performance analysis of different EDS algorithms in biomedical application (e.g. detection of the fetus heart beat from the mother heart beat and fetus heartbeat). The second subpart includes the performance of the EDS, Fast EDS (FEDS), Recursive or Least Square EDS (REDS or LSEDS) and Optimal EDS (OEDS) using Quadrature Amplitude Modulation (QAM) in time domain and design, implementation and performance analysis of these algorithms using semi blind fractionally spaced equalizer technique in time domain.