Abstract: The present invention eliminates the need for an anti-aliasing filter in a receiver that employs an analog-to-digital converter. By maintaining a predetermined relationship between a local oscillator frequency and the sampling frequency of the analog-to-digital converter, aliasing that would normally occur in the desired pass band is avoided. More specifically, the frequency of the periodic signal provided to the mixer is an integer multiple of half the sampling rate of the analog-to-digital converter. In a preferred, non-limiting example embodiment, the sampling rate of the analog-to-digital converter FADC and the frequency of the local oscillator FLO are related by the following: FLO=n*FADC/2, where n is any positive integer.

Abstract: The present invention eliminates the need for an anti-aliasing filter in a receiver that employs an analog-to-digital converter. By maintaining a predetermined relationship between a local oscillator frequency and the sampling frequency of the analog-to-digital converter, aliasing that would normally occur in the desired pass band is avoided. More specifically, the frequency of the periodic signal provided to the mixer is an integer multiple of half the sampling rate of the analog-to-digital converter. In a preferred, non-limiting example embodiment, the sampling rate of the analog-to-digital converter FADC and the frequency of the local oscillator FLO are related by the following: FLO=n * FADC/2, where n is any positive integer.

Abstract: A digital-to-analog signal conversion method and apparatus provide increased dynamic range. An input signal is mapped to plural digital-to-analog converters. Outputs from two or more of the digital-to-analog converters are combined to generate an output signal having a greater signal-to-noise-and-distortion ratio than would be achieved with a single digital-to-analog converter. In a preferred example embodiment, the output signals are combined without including a quantization noise associated with each of the digital-to-analog converters. Indeed, the combined signal includes the quantization noise associated with only one of the digital-to-analog converters.

Abstract: The present invention reduces the peak-to-average power ratio (PAR) of a signal while at the same time providing improved signal-to-noise-and-distortion and increased dynamic range. In the context of a transmitter, the PAR of an input signal is reduced so that one or more elements of a transmitter can be operated with increased dynamic range. However, the initial PAR is restored before the signal is transmitted thereby removing distortion generated as the result of the PAR reduction. The initial PAR is reduced in the digital domain, converted into the analog domain, and then restored in the analog domain.