Performance Signatures for Dual-Polarized Transmission of M-QAM Signals Over Fading Multipath Channels

Abstract

Performance signatures for dual‐polarized transmission of M‐state quadrature amplitude‐modulated signals over dispersive multipath digital radio channels are theoretically derived in this work. We report on two major findings. Firstly, we show that for the assumed propagation model, a cross‐coupled interferer exhibits noiselike behavior and impacts on digital radio outage time in direct relation to its power level. Secondly, our theoretical finding is based on a new application of performance signature curves for two cross‐coupled multipath channels. This treatment permits the prediction of multipath‐induced digital radio outage for specified ratios of power in the copolarized and cross‐coupled signals. Theoretical findings are qualitatively supported by measured performance signatures obtained from a laboratory simulation of the model.

Cross-Polarization Interference Cancellation and Nonminimum Phase Fades

“…The method of establishing the optimum reference timing point in all the figures shown is the minimum-peak-distortion, trial-and-error method, described in Ref. 5. To avoid the unnecessary time shifts introduced by the first and second nonminimum phase transfer function models, we will use the third model in the canceler performance evaluation of Section III.…”

“…We use the static modeling of the dual-polarized channels introduced in Ref. 5 to emulate snapshots of fadings of the main (reference) and the cross-coupled paths. This simple model follows the results of recent measurements cited in Ref.…”