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

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.