Patent ID: 7110732
Filing Date: 2006-09-19
Classification: H04B

Abstract:
1. A subsampling receiver, comprising: a first bandpass filter coupled to receive a modulated signal, the modulated signal including at least one carrier signal at radio frequencies, modulated by a payload signal having frequencies significantly lower than the carrier signal and within a first bandwidth, the first bandpass filter passing frequencies within a frequency band at least as wide as the first bandwidth in a range including the at least one carrier signal; a first sample and hold circuit, having an input coupled to the first bandpass filter, for sampling the modulated signal at a sampling frequency substantially lower than the frequency of the at least one carrier signal; a first analog to digital converter, coupled to the first sample and hold circuit, for digitizing the sampled modulated signal to produce a digital signal at a baseband frequency and corresponding to the payload signal; first and second digital mixers, each coupled to the output of the first analog to digital converter, for applying a sequence of varying amplitude values to the digitized sampled modulated signal at a frequency that is one-fourth of the sampling frequency; and first and second digital low pass filters coupled to the outputs of the first and second digital mixers, respectively; wherein the sequence applied by the second digital mixer is phase-shifted from the sequence applied by the first digital mixer; and wherein the first and second digital mixers present digital sequences corresponding to first and second components of the payload signal.