Patent ID: 7542520

Claim:
An apparatus that includes a digital modulator, the digital modulator comprising: a digital filter configured to receive a pulsed input comprising a series of pulses, process the series of pulses as if the series of pulses is a series of impulses, and generate a predetermined and fixed sequence of instantaneous digital frequency samples as outputs in response to each pulse, wherein the generated instantaneous digital frequency samples represent a predetermined type of filtering of the series of impulses; an integrator configured to receive and integrate the instantaneous digital frequency samples to generate a sequence of digital phase samples; and a look-up table (LUT) stage configured to receive the digital phase samples and to generate digital samples of a complex baseband signal in response to each digital phase sample; wherein a number of bits used to represent each generated instantaneous digital frequency sample is selected based upon a resolution of a frequency variation associated with the complex baseband signal, and wherein a number of bits used to represent each generated digital phase sample is selected based upon a unit circle in a complex plane divided by a resolution of the generated sequence of digital phase samples.