An IF Cross-Pol Canceller for Microwave Radio Systems

This paper discusses cross-pol cancellation for microwave radio system applications. A model for cross-pol interference coupling during multipath fades is postulated and some preliminary performance goals are presented. A design for an IF canceller consisting of cross-coupled adaptive tapped delay lines and a digital controller is presented and discussed. Predicted canceller performance as a function of tap spacing and number is discussed and compared to measured data. The design of a two-channel, dual-polarized lab fade simulator is presented, and methods to characterize canceller performance and fade parameters are also briefly discussed.

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