Pulsed RF generator, pulsed RF transmitter and related methods of operation

An RF pulse generator comprising:

• first and second lasers respectively generating first and second RF optical tones that are phase locked and frequency-offset by a difference corresponding to an RF carrier frequency;
• an optical combiner in optical communication with the first and second lasers to receive and combine the first and second optical tones into a heterodyned optical signal having a beat frequency equal to the RF carrier frequency;
• an optical modulator configured to receive a periodic electrical gating signal and to modulate the heterodyned optical signal to produce a pulsed optical signal having a duty cycle less than 10%;
• and
• a photodetector configured to receive the pulsed optical signal to generate a pulsed RF electrical signal having pulses at the RF carrier frequency,
• wherein the duty cycle is configured such that the photodetector produces a peak RF output power during each pulse that is at least double a maximum continuous-wave output power of the photodetector.

A method for generating a pulsed radio frequency (RF) signal, the method comprising:

• generating a first optical tone at a first frequency with a first laser and a second optical tone at a second frequency with a second laser, wherein the first and second frequencies are offset from one another by a set difference;
• combining the first and second optical tones to provide an optical signal comprising a combination of the first and second optical tones;
• providing a periodic electrical signal to an optical switch to regularly switch the optical switch between an on state and an off state, wherein in the on state, the optical switch passes the optical signal, and, in the off state, the optical switch blocks the optical signal, such that the optical switch outputs a pulsed optical signal comprising a periodic sequence of optical pulses;
• and
• irradiating a photodetector with the pulsed optical signal to generate a pulsed RF electrical signal comprising a periodic sequence of RF pulses, each RF pulse having an RF frequency equal to the set difference.