Multipath Fading Impact on the Quantizer Output Signal Energy Suppression

The article presents the study of ADC performance in the presence of additive noise and input signal fading. The ADC device is represented by the quantization unit with antisymmetric characteristics, which resolves the possible overload situation with either the saturation or the reset strategies. The research is mainly focused on the low-resolution quantizers that are interesting from the practical perspectives of implementation in the Massive-MIMO systems with the hundreds of antenna elements. The input signal fading is accounted for by assuming that the instantaneous channel coefficient follows the complex Nakagami-m distribution. Based on the obtained earlier closed-form expressions for the ADC output signal statistics an energy suppression coefficient (as a quantifying measure of the induced distortions) was evaluated and analyzed for various system and channel parameters values. The possible ranges of analyzed parameters values yielding minimum suppression are calculated, and the worst-case scenarios are determined.