Iterative receiver design for broadband wireless communication systems via expectation maximization (EM) based algorithms

Abstract

Wireless communication systems are good choices to satisfy the growing demands on high-rate, high-quality communications for today's users. Due to the severe propagation environment, the quality of communication relies heavily on the channel information at the receiving side. In this thesis, the Expectation Maximization (EM) algorithm, an iterative algorithm to find the Maximum-Likelihood (ML) estimates, is used to design iterative receivers in wireless communications. More explicitly, in this thesis, the EM algorithm is used to estimate the channel coefficient as well as the frequency offset in Multi-Input Multi-Output (MIMO) systems with a general assumption of having multiple frequency offsets. It is also used for joint channel estimation and data detection in Single-Input Multi-Output (SIMO) systems under the correlated noise environment. The channel estimation and detection in the popular block-based transmission such as Single carrier cyclic-prefix (SCCP), Multicarrier code division multiple access (MC-CDMA), Cyclic-prefix code division multiple access (CP-CDMA) and Interleaved frequency division multiple access (IFDMA) are also investigated using the EM algorithm.