Thesis (M.Eng.) - Asian Institute of Technology, 1995

A Thesis submitted in partial fulfillment for requirement for the degree of Master of Engineering.

Unlike noise CCI signals should have a particular pattern. This leads to the fact that it should somehow be possible to be compensated. An attempt has been made in the present work to track the states of the cochannel interference signal without having any knowledge of its timing or training sequence and subsequently compensate it. A modified algorithm has been proposed and tested. The simulation results using GSM 05 .05 channel have been presented and compared to that of an RLS DFE and an RLS DFE with the algorithm used by CHEN et al., (1994), the algorithm that has been modified in the present work. It has been found that the an RLS DFE with the algorithm of CHEN et al., (1994) has poorer, though not by a significant amount performance than an RLS DFE. The modified algorithm too gives virtually no improvement over an RLS DFE. Also found is that the algorithm given by CHEN et al. (1994) gives cochannel states of which a pair always gets dragged towards the zero value. In the new algorithm the magnitude and phase shift in the updated cochannel state is incorporated in all the states. This keeps them always in a circle and symmetrical positions. The cohannel states obtained in this algorithm drift around the states of the constellation.