Comparative analysis and performance of two predictive fadedetection schemes for Ka-band fade countermeasures

摘要

The design of Ka-band satellite fade countermeasure (FCM) systemsnis conditioned by the detection/prediction algorithm to be includednwithin practical DSP-based FCM controllers. It depends upon the abilitynof systems to efficiently integrate the dynamic and stochastic nature ofnthe Ka-band fading process which is dominated by rain attenuation andnamplitude scintillation. The paper analyzes the modeling and statisticalnperformance of two predictive fade detection algorithms. Prediction isnintroduced as a way to minimize the impact of the finite response timenon the BER/throughput of practical FCM systems. Both fixed (FDM) andnvariable (VDM) detection margin strategies are introduced and comparednin terms of their margin requirements, FCM utilization factor, andnchannel capacity utilization. The VDM is shown to be more efficient thannits fixed counterpart. The long-term BER availability and average userndata throughput of a VDM/fixed-FEC/adaptive transmission rate FCM arenthen evaluated for a typical low-power low-rate Ka-band in-bound VSATnlink