Entropy Agc - An Optimized Agc In Severe Jamming Environments

As the trend of integrating GNSS (Global Navigation Satellite System) with other wireless communications becomes prevalent, jamming tolerance ability is emerging as an essential topic. In an anti-jamming system, the design of AGC (Automatic Gain Control) operation has significant influences on the jamming immunity of the receiver. However, conventional AGC which are designed for some assumptive input signal model cannot guarantee the optimal control under various ambient jamming scenarios and cause extra degradation in the output CN0 (power-to-noise power density ratio). The purpose of this research is to find an AGC control algorithm to perform properly regardless of the changing input signal models. Therefore, a novel AGC control methodology, the Entropy AGC, is proposed. The Entropy AGC estimates the proper occurrence probabilities of each ADC step without the need for a priori information of the environment. To evaluate the AGC performance, various jamming environmental tests are simulated using the Monte-Carlo method. It is verified that an Entropy AGC can reach optimal gain control in the presence of interferences as well as in a jamming-free environment. The jamming mitigation ability of the proposed AGC with anti-jamming system is also shown in the paper.