US 11,838,056 B2
Hybrid photonic integrated circuits for ultra-low phase noise signal generators
Farzad Mokhtari-Koushyar, Austin, TX (US); Thien-An Nguyen, Austin, TX (US); Taran Huffman, Austin, TX (US); and Brian Mattis, Austin, TX (US)
Assigned to GenXComm, Inc., Austin, TX (US)
Filed by GENXCOMM, INC., Austin, TX (US)
Filed on May 5, 2022, as Appl. No. 17/737,178.
Claims priority of provisional application 63/271,703, filed on Oct. 25, 2021.
Prior Publication US 2023/0130434 A1, Apr. 27, 2023
Int. Cl. H04B 10/508 (2013.01); G02B 6/12 (2006.01); H04B 10/50 (2013.01); G02B 6/293 (2006.01)
CPC H04B 10/508 (2013.01) [G02B 6/12004 (2013.01); G02B 6/12007 (2013.01); H04B 10/503 (2013.01); G02B 6/29352 (2013.01); G02B 2006/12061 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A signal generator comprising:
a housing;
a photonic integrated circuit disposed within the housing and comprising:
a laser light source configured to output light centered at an optical carrier frequency;
a waveguide configured to confine light output from the laser light source;
a first resonator configured to:
receive as input light confined by the waveguide output; and
provide as output linewidth-reduced light;
a main resonator configured to:
receive as input the linewidth-reduced light; and
provide as output a soliton pulse train;
a second resonator configured to:
receive as input the soliton pulse train;
attenuate residual optical carrier frequency components from the soliton pulse train; and
provide as output a filtered soliton pulse train; and
a photodiode configured to:
receive as optical input the filtered soliton pulse train; and
provide as electrical output a first periodic electric signal; and
a direct digital synthesizer disposed within the housing and comprising a phase accumulator input conductively coupled to the photodiode, the phase accumulator input configured to receive as input the first periodic electric signal and the direct digital synthesizer configured to provide as output of the signal generator a second periodic electric signal.