System for preventing of crosstalk between a raw digital output signal

Abstract

The raw digital output signal generated at the transmitter by an ADC is XOR'd with a sequence of pseudo-random numbers to generate an encoded output signal. This removes all correlation between the analog input signal and the encoded output signal. Coherence between the encoded output signal and the analog input signal is prevented and the effects of crosstalk to the analog input signal are mitigated. In a first embodiment of the invention, the sequence of pseudo-random numbers is a sequence of one-bit pseudo-random numbers that are XOR'd with each bit of the raw digital output signal. In a second embodiment, the sequence of pseudo-random numbers is a sequence of N-bit pseudo-random numbers that are XOR'd with the N-bit words of the digital output signal. To recreate the original raw digital output signal in the receiver, a second XOR operation is performed between the encoded output signal and the sequence of pseudo-random numbers. Alternatively, a pseudo-random number generator located in each of the transmitter and receiver are synchronized to generate equal sequences of PRNs that encode the raw digital output signal and decode the encoded output signal. Intermediate digital pipelining may be used to add a decoding bit from the pseudo-random-number generator to the encoded output signal. Such additional bit may be stored in memory with the encoded output signal to permit later decoding.