A receiver comprising a sigma-delta analog-to-digital converter (SigmaDelta ADC) can be utilized in one of four configurations, as a subsampling bandpass receiver, a subsampling baseband receiver, a Nyquist sampling bandpass receiver, or a Nyquist sampling baseband receiver. For subsampling SigmaDelta receivers, the sampling frequency is less than twice the center frequency of the input signal into the SigmaDelta ADC. For Nyquist sampling SigmaDelta receivers, the sampling frequency is at least twice the highest frequency of the input signal into the SigmaDelta ADC. For baseband SigmaDelta receivers, the center frequency of the output signal from the SigmaDelta ADC is approximately zero or DC. For bandpass SigmaDelta receivers, the center frequency of the output signal from the SigmaDelta ADC is greater than zero. The sampling frequency can be selected based on the bandwidth of the input signal to simplify the design of the digital circuits used to process the output samples from the SigmaDelta ADC. Furthermore, the center frequency of the input signal can be selected based on the sampling frequency and the bandwidth of the input signal. The SigmaDelta ADC within the receiver provides many benefits.
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