| In the first part of the thesis, blind and semi-blind channel identification are studied for 3G W-CDMA communications by using receive diversity where one transmit antenna and two receive antennas are employed. A blind channel identification scheme is proposed by applying the Cross-Relation Method to a derived SIMO channel model. This blind scheme is then augmented to a semi-blind one by using the known pilot symbols as constraints. In the second part of the thesis, semi-blind channel identification by employing transmit diversity is researched where two transmit antennas and one receive antenna are used. First, the orthogonal transmit diversity scheme by pre-coding information symbols is studied. Secondly, the orthogonal transmit diversity scheme based on multiple code transmission is considered. Thirdly, the transmit diversity scheme called delay transmit diversity is investigated. Semi-blind channel identification algorithms are derived by applying the Cross-Relation Method together with pilot symbols to these diversity schemes. In the third part of the thesis, semi-blind channel identification through employing delay spread diversity is considered where a single transmit antenna and a single receive antenna are used. A semi-blind channel identification method is developed by applying both the Cross-Relation Method and pilot symbols. To evaluate the proposed blind and semi-blind channel identification algorithms, a space-time Rake receiver is simulated where the blind and semi-blind channel estimates are used in coherent demodulation. |
