An antenna subsystem receives an analog desired signal, noise, and interference via a communication channel. The desired signal includes modulated encoded digital information. A local oscillator (LO) modulation subsystem generates a modulated LO. The LO modulation subsystem generates a modulated LO to maximize the symbol signal-to-noise ratio of the decoded digital information based on a plurality of: the desired signal, the interference and the noise expected in the communication channel, the characteristics of the converter, and the ability of the DSP to remove the Modulated LO from the converted signal. A mixer mixes the received signal and the modulated LO. A converter converts the mixed signal from analog to digital. A digital signal processor (DSP) removes the modulated LO and desired signal modulation, and decodes the desired signal encoded digital information.