Ultra-low phase noise transfer oscillator microwave reference via phase modulated mode-locked laser feedback
AssigneeRaytheon Company
InventorDarrell L. Young
Life of this patent
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Abstract
A system includes a mode-locked laser (MLL) configured to receive a first radio frequency (RF) reference signal, and based on the first RF reference signal, generate an optical frequency comb (OFC). The system further includes a wavelength conversion medium configured to receive the OFC, and based on the OFC, generate at least one photonic reference signal. The system further includes a transfer oscillator (TO) circuit configured to receive the OFC and the at least one photonic reference signal, and generate the first RF reference signal based on the OFC and the at least one photonic reference signal.
Claims20
A system comprising:
- a mode-locked laser (MLL) configured to:
- receive a first radio frequency (RF) reference signal, and
- based on the first RF reference signal, generate an optical frequency comb (OFC);
- a wavelength conversion medium configured to:
- receive the OFC, and
- based on the OFC, generate at least one photonic reference signal;
- and
- a transfer oscillator (TO) circuit comprising a plurality of TO channels, the TO circuit configured to:
- receive the OFC and the at least one photonic reference signal,
- generate, via each TO channel, a respective processed RF signal
- based on the OFC and the at least one photonic reference signal, and
- coherently sum each respective processed RF signal to generate the first RF reference signal.
A method comprising:
- generating, by a mode-locked laser (MLL), an optical frequency comb (OFC);
- generating, by a wavelength conversion medium, based on the OFC, at least one photonic reference signal;
- generating, by each of a plurality of transfer oscillator (TO) channels of a TO circuit, a respective processed RF signal based on the OFC and the at least one photonic reference signal;
- coherently summing each respective processed RF signal to generate a first radio frequency (RF) reference signal;
- and
- modulating a phase of the MLL based on the first RF reference signal.
A transfer oscillator (TO) circuit comprising at least one TO channel, each TO channel comprising:
- an x-band filter configured to:
- receive a first RF signal;
- and
- generate a first filtered RF signal;
- and
- a plurality of direct digital synthesizers (DDSs), each DDS configured to:
- receive a photonic reference signal;
- and
- generate an xth RF signal based on the photonic reference signal,
- wherein each TO channel is configured to generate a processed RF signal based on the first filtered RF signal and each of the xth RF signals;
- and
- wherein the TO circuit is configured to:
- coherently sum the processed RF signal from each TO channel;
- and
- generate a first RF reference signal based on the coherent sum.
Dependencies are inferred from the claim text.