| 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. |
