Discussion of factors influencing the design and implementation of echo cancellation in full duplex bi-directional transmission systems

Outlines design considerations in echo cancellation and compares various adaptation algorithms in some tutorial detail, thus providing motivation for the two investigated algorithms, namely: the least mean square stochastic update (LMS) algorithm and the fast Kalman algorithm. The latter, though considerably more complicated to implement than the stochastic gradient algorithm, can yield an improvement in the speed of adaptation. This is particularly true for the data canceller case, where the data symbols can be chosen during a training period at the initialisation of the connection