A heuristic approach to higher order statistical models for the combined process of a direct-sequence signal in additive white Gaussian noise and continuous wave interference after an adaptive 2-bit ADC-nonlinearity

The severe performance degradation of digital direct-sequence spread-spectrum receivers in deterministic types of interference, due to the inherent analog-to-digital converter nonlinearities is well known. In this paper we focus on the models for the combined process of a direct-sequence signal in additive white Gaussian noise and continuous wave interference after an adaptive 2-bit ADC-nonlinearity. The signal's magnitude distribution and zero-crossings are analyzed. Five models are presented and compared to simulations. The figure of merit uses an integral algorithm to compare the different models. The advantages and disadvantages of each model are presented. The general advantage of all the models are that less computation resources are needed.