New techniques for adaptive equalisation of multipath propagationon digital radio

摘要

The possibilities of improving the performance of the adaptiveequaliser operation in microwave radio channels are investigated byexploring the following: (1) deliberately enhancing equalisation contentin the transmitted signal which can be readily used for adaptiveequalisation at the receiving end; and (2) exploiting any available apriori knowledge of the channel, and incorporating this in the equaliseradaptation process. An example of the first approach, namely dataassisted equalisation (DAE), has been suggested by Muthukkumarasamy andIngram (see Proc. of the Fourth Region 10 Int. Conf.-TENCON '89, p.916,1989) for baseband transmission systems. This technique allowsintroduction of equalisation data by purely digital methods. The use ofDAE methods in carrier wave modulated systems is investigated