Method and apparatus for synthesis of wideband low phase noise radio frequency signals

摘要

An apparatus for synthesizing wideband radio frequency signals in the microwave region has mostly digital components. The apparatus processes and converts a signal from a stable single-frequency electrical oscillator into a lower or higher frequency electrical signal without using analog multiplier or mixer circuits. An apparatus for synthesizing a fixed phase-stable RF reference signal for use in a radar transceiver includes a phase-stable electrical oscillator which produces a single frequency sinusoidal reference signal. The apparatus converts the reference signal to an arbitrary higher or lower fixed frequency using digital logic and signal delays. The apparatus comprises low-jitter comparator, an impulse former, a gearbox retiming circuit and a recirculator circuit. An apparatus for providing wideband FM modulation of an RF signal includes circuitry for synthesizing a radio frequency signal having arbitrary tuning of center frequency and dynamic command of wideband FM and retaining low phase noise performance of the synthesized signal.

主权项

1. An apparatus for synthesizing sinusoidal radio frequency signals comprising:
an oscillator configured to output a first sinusoidal signal having a first frequency; an impulse former configured to convert the first sinusoidal signal into a first pulse train having a first timing interval between pulses; a gearbox configured to dilate or compress the first timing interval between pulses of the first pulse train to thereby create a second pulse train having a second timing interval between pulses and a second frequency; a recirculator configured to delay and add pulses in the second pulse train, to the second pulse train itself, to thereby form a third pulse train comprising pulses having a third timing interval between pulses and a third frequency, the third timing interval being less than the second timing interval; and circuitry to convert the third pulse train into an RF signal.