US 12,281,939 B2
Adjustable signal source with low phase noise
Meysam Bahmanian, Bochum (DE); and Johannes Christoph Scheytt, Dorsten (DE)
Assigned to UNIVERSITÄT PADERBORN, Paderborn (DE)
Appl. No. 18/717,518
Filed by UNIVERSITÄT PADERBORN, Paderborn (DE)
PCT Filed Dec. 9, 2022, PCT No. PCT/EP2022/085114
§ 371(c)(1), (2) Date Jun. 7, 2024,
PCT Pub. No. WO2023/105026, PCT Pub. Date Jun. 15, 2023.
Claims priority of application No. 10 2021 214 164.1 (DE), filed on Dec. 10, 2021.
Prior Publication US 2025/0044151 A1, Feb. 6, 2025
Int. Cl. G01J 1/44 (2006.01); G01J 1/08 (2006.01)
CPC G01J 1/44 (2013.01) [G01J 1/08 (2013.01); G01J 2001/446 (2013.01)] 7 Claims
OG exemplary drawing
 
1. An adjustable signal source with low phase noise, comprising:
an optical-microwave phase detector, comprising:
an intensity modulator having an optical signal input, a modulation input, a first output, and a second output,
a first photodiode which can be irradiated by light from the first output during operation,
a second photodiode which can be irradiated by light from the second output during operation,
wherein the first photodiode and the second photodiode are connected in series in a biased manner during operation,
wherein a tap for a tap signal is arranged between the first photodiode and the second photodiode,
further comprising a first controllable DC power source,
wherein an offset current is adjustable at the tap during operation by means of the first controllable DC power source, whereby the symmetry of the optical-microwave phase detector is canceled by the offset current during operation,
wherein the tap is routed to a low-pass filter with any potential offset current,
wherein a low-pass-filtered tap signal is provided to an adjustable oscillator.