Wideband phase modulation methods and apparatus

摘要

A wideband phase modulator comprises a multiphase generator, a phase selector, and a phase adjuster. The wideband phase modulator is configured to receive an N-bit digital phase-modulating signal comprising a timed sequence of N-bit phase-modulating words, where N is a positive integer representing the bit resolution of the N-bit digital phase-modulating signal. The multiphase generator generates a plurality of coarse carrier phases, all having the same carrier frequency but each offset in phase relative to the other. The M most significant bits of the N-bit phase-modulating words are used to form M-bit phase select words that control the output phase of the phase selector. The phase adjuster performs a precision rotation operation, whereby a selected coarse carrier phase is adjusted so that the phase of the resulting final precision phase-modulated signal more closely aligns with a desired precision phase.

主权项

1. A wideband phase modulator, comprising:
a multiphase generator configured to generate a plurality of coarse carrier phases; a phase selector configured to select from among said plurality of coarse carrier phases; and a phase adjuster configured to adjust the phase of a selected coarse carrier phase from a coarse phase to a precision phase by interpolating between a selected coarse carrier phase and an adjacent coarse carrier phase or by adjusting around a selected coarse carrier phase, wherein the coarse carrier phases generated by said multiphase generator are generated without modulating an oscillator in a phase-locked loop by an information-bearing phase-modulating signal.