CN-117544233-B - Broadband low noise microwave photon link

CN117544233BCN 117544233 BCN117544233 BCN 117544233BCN-117544233-B

Abstract

The invention relates to a broadband low-noise microwave photon link which comprises a low-noise light source, a modulator connected with the low-noise light source and a photoelectric detector connected with the modulator, wherein the low-noise light source is used for generating laser signals, and sequentially carrying out optical amplification and narrowband photon filtering on the laser signals so as to output high-power low-noise laser signals as optical carriers of an electro-optical intensity modulator. In the invention, RIN noise of the laser source is restrained by adopting a mode of combining optical amplification and optical filtering, a high-power low-noise laser signal is output, the noise coefficient of a microwave photon link can be reduced, and the method can be used in the application fields of radar, electronic warfare, communication, navigation, monitoring and the like.

Inventors

XIAO YONGCHUAN
CHEN NUO
QU PENGFEI
ZHANG HAO
YU CAIBIN
Wang maoxu
PENG YUBIN

Assignees

中国电子科技集团公司第四十四研究所

Dates

Publication Date: 20260512
Application Date: 20231114

Claims (7)

1. The broadband low-noise microwave photon link is characterized by comprising a low-noise light source, a modulator connected with the low-noise light source and a photoelectric detector connected with the modulator, wherein the low-noise light source is used for generating laser signals, and sequentially carrying out optical amplification and narrow-band photon filtering on the laser signals so as to output high-power low-noise laser signals as optical carriers of the photoelectric intensity modulator; The low noise light source comprises The laser assembly is used for outputting laser signals and comprises a high-power low-noise DFB laser, a laser automatic temperature control circuit and a laser automatic power control circuit; The optical amplifier is used for amplifying the power of the laser signal output by the laser component and outputting a high-power laser signal; an optical filter, which is a narrow-band photon filter, for performing signal gating and noise suppression on the high-power laser signal output by the optical amplifying unit and outputting a high-power low-noise laser signal, and The wavelength locking unit is used for regulating and controlling the wavelength of the laser output by the laser component according to the power change condition of the laser signal output by the filtered narrow-band photon filter, so as to lock the wavelength of the laser signal output by the laser component; the control method for the wavelength locking unit to lock the wavelength of the laser signal output by the laser component comprises the following steps: S101, powering up and starting a high-power low-noise DFB laser; S102, increasing the refrigeration current of a semiconductor refrigerator of the automatic temperature control circuit of the laser; s103, detecting the power change condition of the laser signal output after being filtered by the narrow-band photon filter, and if the power of the laser signal is increased, returning to the step S102, otherwise, executing the step S104; s104, reducing the refrigeration current of a semiconductor refrigerator of the automatic temperature control circuit of the laser; s105, detecting the power change condition of the laser signal output after being filtered by the narrow-band photon filter, if the power of the laser signal is increased, returning to the step S104, otherwise, returning to the step S102.
2. The broadband low-noise microwave photonic link of claim 1, wherein the optical amplifier is a high-power erbium-doped fiber amplifier.
3. The broadband low-noise microwave photonic link of claim 1, wherein the modulator comprises an electro-optical intensity modulator and a bias control circuit, and the photodetector is a broadband high-speed photodetector.
4. The broadband low-noise microwave photon link according to any one of claims 1-3, wherein the passband shape of the narrowband photon filter is a Gaussian filter shape.
5. The broadband low-noise microwave photonic link of any one of claims 1 to 3, wherein the narrowband photonic filter comprises a Mach-Zehnder interferometer and a micro-ring resonator, the Mach-Zehnder interferometer is provided with a first interference arm and a second interference arm, the micro-ring resonator is optically coupled with the first interference arm of the Mach-Zehnder interferometer, and the second interference arm of the Mach-Zehnder interferometer is respectively connected with the wavelength locking unit and the modulator.
6. The broadband low-noise microwave photonic link of claim 5, wherein the narrowband photonic filter is fabricated using a silicon nitride waveguide.
7. The broadband low-noise microwave photonic link of claim 5, wherein the narrow-band photonic filter has a transfer function of Wherein T 1 (λ) represents a transfer function of a first interference arm of the narrowband photon filter, T 2 (λ) represents a transfer function of a second interference arm of the narrowband photon filter, E 0 (T) represents an expression of an optical signal input to the narrowband photon filter, E 1 (T) represents an expression of an optical signal output from the first interference arm of the narrowband photon filter, E 2 (T) represents an expression of an optical signal output from the second interference arm of the narrowband photon filter, κ represents an optical field coupling coefficient between the micro-ring resonator and the first interference arm, α represents an optical waveguide loss of the narrowband photon filter, β represents a propagation constant of the optical waveguide, L represents a circumference of the micro-ring resonator, λ represents a wavelength of light, and N eff represents an effective refractive index of the optical waveguide of the narrowband photon filter.

Description

Broadband low noise microwave photon link Technical Field The invention belongs to the technical field of microwave photons, and relates to a broadband low-noise microwave photon link. Background The microwave photon technology is a new technology formed by deeply fusing the photon technology and the microwave technology, has the flexible ubiquitous advantage of the microwave technology and the advantage of broadband low transmission loss of the photon technology, so that the microwave photon technology is widely studied at home and abroad. The microwave photon technology has various advantages, including wide working frequency band, large instantaneous bandwidth, long transmission distance, strong parallel capability, light weight, high density integration, electromagnetic interference resistance and the like, so the microwave photon technology has great application potential in the fields of radar, communication, electron contrast, measurement and control and the like of military and civil dual-purpose. Although the microwave photon technology has many advantages, because the laser, the modulator and the photoelectric detector of the microwave photon link core are all active devices, extra noise can be introduced in the electro-optical-to-photoelectric conversion process of microwave signals, the noise performance can be further deteriorated after the amplification of the optical amplifier, and the high noise can reduce the key performance indexes such as the sensitivity, the dynamic range and the detection precision of the system, so that the noise suppression becomes the key for realizing the high-performance microwave photon system. The literature reports schemes such as using modulator undershoot or using balanced detectors to reduce noise figure, but modulator undershoot can greatly sacrifice bandwidth, balanced detection schemes not only increase system complexity but also cannot be pulled far, thus limiting the application of microwave photon technology. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a broadband low-noise microwave photon link. In order to achieve the above purpose, the present invention provides the following technical solutions: The broadband low-noise microwave photon link comprises a low-noise light source, a modulator connected with the low-noise light source and a photoelectric detector connected with the modulator, wherein the low-noise light source is used for generating laser signals, and sequentially carrying out optical amplification and narrow-band photon filtering on the laser signals so as to output high-power low-noise laser signals as optical carriers of the photoelectric intensity modulator. Further, the low noise light source comprises The laser component is used for outputting a laser signal; The optical amplifier is used for amplifying the power of the laser signal output by the laser component and outputting a high-power laser signal; an optical filter, which is a narrow-band photon filter, for performing signal gating and noise suppression on the high-power laser signal output by the optical amplifying unit and outputting a high-power low-noise laser signal, and The wavelength locking unit is used for regulating and controlling the wavelength of the laser output by the laser component according to the power change condition of the laser signal output by the narrow-band photon filter after filtering, so as to lock the wavelength of the laser signal output by the laser component. Further, the laser assembly includes a high power low noise DFB laser, a laser automatic temperature control circuit, and a laser automatic power control circuit. Further, the control method for locking the wavelength of the laser signal output by the laser component by the wavelength locking unit comprises the following steps: S101, powering up and starting a high-power low-noise DFB laser; S102, increasing the refrigeration current of a semiconductor refrigerator of the automatic temperature control circuit of the laser; s103, detecting the power change condition of the laser signal output after being filtered by the narrow-band photon filter, and if the power of the laser signal is increased, returning to the step S102, otherwise, executing the step S104; s104, reducing the refrigeration current of a semiconductor refrigerator of the automatic temperature control circuit of the laser; s105, detecting the power change condition of the laser signal output after being filtered by the narrow-band photon filter, if the power of the laser signal is increased, returning to the step S104, otherwise, returning to the step S102. Further, the optical amplifier is a high-power erbium-doped fiber amplifier. Further, the modulator comprises an electro-optical intensity modulator and a bias control circuit, and the photoelectric detector is a broadband high-speed photoelectric detector. Further, the passband shape of the narrowband photon filter is a g