This paper presents a proportional–integral–derivative (PID)-based automatic gain control (AGC) approach for satellite communications attacked by partial-time partial-band additive white Gaussian noise (AWGN) jamming. The analysis based on the stochastic model predictive control (SMPC) shows that the AGC performance depends on the accurate characterization of the jammed signal in the future time instants. However, such characterization is generally unavailable. To overcome the limitations of the existing AGC schemes without considering the future trend of the signal amplitude tracking errors (i.e., the difference between the average amplitude and the desired amplitude), the proposed approach uses the derivative term of signal amplitude tracking errors for anticipatory control and the integral term in the PID control to eliminate steady-state errors. Furthermore, different block sizes of the sampled signals are used for computing and selecting gain control values to achieve a good trade-off between fast response and robustness to noise/jamming. Extensive simulations of a system based on the typical satellite transponder link using Quadrature Phase Shift Keying (QPSK) modulated input signals and AWGN noise/jamming demonstrate that the proposed approach can achieve better control performance for maintaining the desired signal amplitude range and smaller bite error rate (BER) in the case of AWGN jamming, as compared with the existing AGC schemes.
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