77 results about "Optical delay line" patented technology

The invention relates to the field of electromagnetic field technology and radio frequency signal testing, in particular to a radio frequency standard field generation system and method based on near-field beam forming, and the system comprises a control unit, a radio frequency signal generation unit, a radio frequency field control unit and a broadband radiation antenna array. The control unit carries a near-field electromagnetic wave synthesis mathematical model and is used for receiving a target field type setting requirement and calculating excitation amplitude and injection compensation phase required by each radiation unit configured in the broadband radiation antenna array; the radio frequency signal generation unit comprises a pulse modulation laser source and a plurality of semiconductor radiation units and is used for generating high-power programmable radio frequency signals; the radio frequency field control unit comprises an optical delay line and an FPGA matrix and is used for performing amplitude and phase regulation and control on the high-power programmable radio frequency signal output by the radio frequency signal generation unit; and the broadband radiation antenna array is used for receiving the regulated radio frequency signal and radiating the regulated radio frequency signal to the near-field space of the darkroom, and a target field pattern is formed through multi-unit electric field vector superposition.

The invention discloses a reflective pumping detection nondestructive testing device and method capable of saturatively absorbing uniformity in a mirror surface. The device is based on a wavelength degeneracy pumping-detection principle, and comprises a femtosecond laser source, a beam splitter, an optical delay line, a double-frequency optical chopper, a two-dimensional precision translation stage, a coaxial focusing system, a spatial filtering diaphragm arranged in a reflection light path, a photoelectric detector, a lock-in amplifier and a signal processing unit. According to the method, different point positions of a sample are accurately positioned through a two-dimensional translation stage, a nonlinear differential reflectance dynamic curve of each point is measured under low power, the maximum differential reflectance and the carrier lifetime are extracted as characteristic parameters, the spatial relative standard deviation of the characteristic parameters is calculated, and lossless and quantitative in-plane uniformity evaluation is realized. According to the method, the interference of the pump light is effectively filtered through the space filtering diaphragm, the signal-to-noise ratio is remarkably improved in combination with the phase-locked amplification technology, and the problem that the nonlinear optical performance uniformity of the saturable absorber mirror cannot be quantitatively evaluated through a traditional method is solved.

The application discloses a quantum random number generator based on feedback adjustment of a comparator threshold value and a random sequence generation method. The quantum random number generator comprises a superluminescent diode, a filter, an erbium-doped fiber amplifier, a fiber coupler with a coupling ratio of 50:50, an optical delay line, a first beam splitter and a second beam splitter with the same splitting ratio, a first optical power meter and a first photodetector connected with the first beam splitter, a second optical power meter and a second photodetector connected with the second beam splitter, a microcontroller connected with the first optical power meter and the second optical power meter, and a comparator connected with the microcontroller, the first photodetector and the second photodetector. The first photodetector and the second photodetector are connected with the comparator through a differential circuit. The application adjusts the threshold voltage to offset the influence of the output characteristics of a light source on the output random number.

A signal processing apparatus, a detection apparatus and a terminal device, which relate to the technical field of detection, and are used for reducing the costs and occupied spaces of optical delay lines. The signal processing apparatus comprises a first frequency modulation group (11), a second frequency modulation group (21) and an optical delay line (400); the first frequency modulation group (11) comprises a first frequency modulation photoelectric loop (110), a second frequency modulation photoelectric loop (210) and a polarization control element (300); the second frequency modulation group (21) comprises a third frequency modulation photoelectric loop (310); the polarization control element (300) is connected among the optical delay line (400), a first beam splitting element (112, 212, 312) in each frequency modulation photoelectric loop (110, 210, 310) and a frequency mixer (114, 214, 314) in each frequency modulation photoelectric loop (110, 210, 310), and is used for outputting optical signals (S11, S21, S31) in the three frequency modulation photoelectric loops (110, 210, 310) to the optical delay line (400) in orthogonal polarization directions, and outputting the delayed optical signals (S11 ', S21 ', S31 ') to the mixer (114, 214, 314) in each frequency modulation optoelectronic circuit (110, 210, 310). The signal processing apparatus can achieve the effect that the three frequency modulation photoelectric loops (110, 210, 310) share the same optical delay line (400), and reduce the number of optical delay lines (400) required to be provided in the signal processing apparatus, and the costs and occupied spaces of the optical delay lines (400).

The invention belongs to the technical field of optical measurement, and relates to an MEMS fatigue evolution law observation device based on off-axis digital holographic microscopy, which comprises a red light super-radiation light-emitting diode light source, a wire grid type beam splitter, an objective lens and a CCD, and is characterized in that a linear polarizer, a half-wave plate and the wire grid type beam splitter are fixedly arranged on a light path emitted by a red light super-radiation light-emitting diode; a half-wave plate, a beam expanding lens group, a plano-convex lens, a beam splitter prism, an objective lens and a sample table are fixedly arranged on an object light path in sequence, a reflector is arranged on a vertical light path, and an optical delay line, the beam expanding lens group and the plano-convex lens are fixedly arranged on a reference light path; after the reference light passes through the reflector and the beam splitter prism, the reference light interferes with the object light reflected by the beam splitter prism on the CCD and is observed. According to the invention, the hologram of the MEMS device under high-frequency vibration can be acquired, and the surface topography of the MEMS device is obtained through computer rapid phase unwrapping, so that the purpose of observing fatigue evolution of the MEMS structure in real time is achieved.

The invention belongs to the technical field of optical precision measurement, and particularly discloses a lens thickness measuring device and method based on opposite coaxial light path interference, which utilizes a common light path design that a 1310nm broadband low-coherence light interference system and a 1550nm narrow-band high-coherence light interference system share one reference arm, and innovatively adopts an opposite coaxial light path structure on a sample arm, so that the thickness of a lens is measured. Meanwhile, interference signals on the front surface and the rear surface of a sample lens are effectively extracted, key parameter measurement of the center thickness of the lens is integrated on a coaxial light path, the structure is simplified, and the complexity of equipment installation and debugging is reduced; the low-coherence light is used for accurately positioning the position of each surface, the high-coherence light is used as a scale for accurately measuring the distance between the surfaces, and the center thickness of the lens is calculated in combination with a specific algorithm, so that non-contact rapid high-precision measurement is realized; in addition, a grating ruler straight stepping motor is introduced to drive a sample arm light path assembly, and measurement of the center thickness of a long-distance lens or a lens group is achieved on the premise that the original scanning range of the optical delay line is kept.

The invention belongs to the technical field of microwave photons, and provides a double-ring photoelectric oscillator and a stabilizing method thereof. The oscillator is provided with a long ring and a short ring and comprises a stabilizing device; the stabilizing device comprises a first piezoelectric ceramic optical fiber stretcher, a motor space light delay line and a second piezoelectric ceramic optical fiber stretcher; generating two optical probe signals; the first optical probe signal is converted into a first electric probe signal through the long ring; a second optical probe signal is converted into a second electric probe signal through the short ring; an electric probe signal is output after being subjected to detection, coupling and power division; the two frequency mixers respectively carry out homodyne frequency mixing on the electric probe signal and the phase-shifted and non-phase-shifted radio frequency signals to generate a zero-frequency error signal; the two phase-locked loops generate compensation control signals according to the error signals; the control signal adjusts an optical fiber delay line; the stability of the two loops is ensured, the problem of combined signal frequency drift caused by neglecting short-loop delay change is solved, the coherence requirement on optical signals is avoided by electric domain combination, and smooth tuning of the output radio frequency signal frequency is realized.

The application discloses a kind of background noise suppression systems of dual optical comb coherent raman spectrum of probe light delay control, by setting the laser that light frequency comb light source module is emitted into probe light and pump light by first beam splitter in probe light delay control module, and setting optical delay line is applied to the probe light with delay amount, utilize the characteristics that the decay time of coherent raman spectrum signal is longer than the decay time of background noise, probe using probe light with delay amount, realize the purpose of inhibiting background noise, it is beneficial to improve the signal-to-noise ratio of dual optical comb coherent raman spectrum measurement system, inhibits spectrum signal distortion.

This invention discloses a delay compensation device, a delay compensation method, and a phased array laser terminal. Multiple transmitting optical paths, a sampling and monitoring module, and a phased array antenna are sequentially connected in communication. Each transmitting optical path includes a first optical delay line and a first high-speed phase shifter. The sampling and monitoring module determines a first delay control parameter and a first phase control parameter, or a second delay control parameter and a second phase control parameter, based on the optical path difference. The first optical delay line performs first optical path difference delay compensation on the laser beam. The first high-speed phase shifter performs first phase difference delay compensation on the laser beam. The phased array antenna performs second optical path difference delay compensation and second phase difference compensation on the laser beam based on the second delay control parameter and the second phase control parameter. In this embodiment, the delay compensation of the laser beam using the first optical delay line, the first high-speed phase shifter, and the phased array antenna solves the phase jump and wavelength dispersion problems in phased array communication and improves communication capacity.

The present invention provides a single sideband signal generator, comprising: a modulator configured to generate a first modulated optical signal and a second modulated optical signal having the same amplitude; and the sideband suppression light circuit based on the first light delay line is used for generating a full-carrier single-side-band signal, and / or the sideband suppression light circuit based on the second light delay line is used for generating a carrier-suppressed single-side-band signal. The present invention simplifies the structure by saving half the space occupied by redundant signal electrodes, and also reduces the RF power consumption by half by removing an RF mixer. The provided single side band (SSB) signal generator has the advantages of compact structure, low cost and energy conservation. By reasonably designing the length of the optical delay line, the generator can be easily expanded to a higher frequency range on the premise of not needing extra cost.

By arranging light source, optical chip, interferometer, photoelectric detection module, sample acquisition module and data processing module, wherein light source is connected to interferometer by optical chip, while both reference path and sample path of optical chip have optical delay line arranged respectively, and optical delay lines are continuously adjustable; optical chip is configured to divide detection light into reference path signal light and sample path signal light, and transmitting reference path signal light and sample path signal light to interferometer by optical delay line continuously adjustable respectively. Comparing with traditional mechanical style TD-OCT system having problem of scanning rate slow, present solution replaces a mechanical movement of reference path in prior art by optical delay lines continuously adjustable, which not only improves scanning rate, but also has smaller volume.

The invention belongs to the technical field of microwave photons, and provides a double-ring photoelectric oscillator with a stabilizing device and a stabilizing method thereof, the double-ring photoelectric oscillator is provided with a long ring, a short ring and a stabilizing device; the stabilizing device comprises a first piezoelectric ceramic optical fiber stretcher and a motor space light delay line; the radio frequency signal source generates a first optical probe signal and a second optical probe signal through modulation; the first optical probe signal is converted into a first electric probe signal after passing through the long ring; a second optical probe signal is converted into a second electric probe signal after passing through the short ring; the first frequency mixer and the second frequency mixer are used for performing homodyne frequency mixing on the electric probe signal and the radio frequency signal to generate a zero frequency error signal; and the two phase-locked loops generate compensation control signals according to the zero-frequency error signals. According to the invention, by outputting the control signal and adjusting the optical fiber delay line, the stability of two loops is ensured, the problem of combined signal frequency drift caused by neglecting short-loop delay change is solved, and the coherence requirement on two paths of optical signals is avoided by electric field combination.

A photonic analog-to-digital conversion (ADC) method and converter based on the optical trapping principle is disclosed. This method utilizes multiple continuous light sources to load sampled analog signals and controls the input of each analog signal to the optical trapping module at equal time intervals via optical delay lines, achieving signal discretization in the time domain. The use of multiple continuous light sources increases the total input power of the photonic ADC system. Furthermore, the multiple optical signals are modulated and delayed by analog signals before being synthesized into a single signal, avoiding the nonlinear effects caused by excessively high total optical power resulting from directly synthesizing multiple continuous light sources. This invention's photonic ADC method based on the optical trapping principle overturns the traditional method of generating pulsed light before photonic sampling, increasing the total input power of the photonic ADC system and effectively offsetting the impact of optical power loss on the conversion accuracy. Based on this method, a high-precision on-chip photonic ADC system can be achieved.

The invention belongs to the technical field of quantum information, and relates to a non-detection photon imaging system based on a single optical fiber integrated nonlinear waveguide. Comprising a continuous tunable pumping laser source, an optical amplifier, an adjustable optical attenuator, a first beam splitter, a first adjustable optical delay line, a first polarization controller, a second polarization controller, a first optical circulator, a nonlinear straight waveguide, a second optical circulator, a first optical filter, a second optical filter, a third optical filter, a fourth optical filter, a third optical circulator, a second adjustable optical delay line and an optical absorption terminal. The system comprises a first light collimator, a first lens, a three-dimensional scanning platform, a second lens, a second light collimator, a second beam splitter, a third polarization controller, a fourth polarization controller, a first single-photon detector, a second single-photon detector and a coincidence measurement unit. Compared with a traditional non-detection photon imaging system, quantum imaging of a transparent object can be achieved only through half of resource expenditure, and robustness is provided for the imaging system through all-fiber integrated configuration.

The invention discloses a high-speed optical switching integrated chip based on an on-chip optical delay line, which comprises a chip substrate, an optical delay line and an optical switch array, the optical delay line is arranged on the chip substrate, the optical switch array is arranged on the chip substrate, and the on-chip optical delay line is arranged on the chip substrate. The input end of the optical switch array is connected with the output end of the optical delay line. The optical switch array comprises: N input ports; the plurality of optical switch units are connected with the N input ports; the M output ports are connected with the output ends of the optical switch units; the plurality of optical switch units are arranged according to a topological structure; the number of the optical delay lines is N, and the N optical delay lines are connected with the N input ports of the optical switch array in a one-to-one correspondence mode. The optical switching integrated chip is composed of N on-chip optical delay lines and an N * M optical switch array. Data are firstly input into the on-chip optical delay line to play a role in optical caching.

The invention belongs to the field of distributed optical fiber sensing monitoring, and discloses a BOCDR distributed optical fiber sensing device based on chaotic optical path matching detection. The device comprises a chaotic light source, an optical isolator, a first optical fiber coupler, an erbium-doped optical fiber amplifier, a grating optical filter, a first optical fiber circulator, a sensing optical fiber, an optical delay line, a second optical fiber coupler, a first photoelectric detector, a second photoelectric detector and a spectrum analyzer, according to the invention, the optical path matching base point is determined through the cross-correlation of the chaos reference light and the chaos pump light, and the distributed measurement of the Brillouin correlation domain reflection is realized by using the chaos optical path matching and coherent beat frequency method, so that the spatial resolution of the system can be improved.

The invention discloses an optical delay line device and an optical delay line system, and relates to the technical field of optical measurement, and the optical delay line device comprises a rotating disc, a cuboid prism, a first plane mirror, a second plane mirror, a first collimator, a second collimator and a driving assembly. A preset included angle is formed between the collimation direction of the first collimator and the collimation direction of the second collimator; the cuboid prism is provided with a first side surface, and the first side surface is arranged at an included angle relative to the first laser emitted by the first collimator; the first side surface is arranged at an included angle relative to the second laser emitted by the second collimator; the driving assembly is in driving connection with the turntable; the driving assembly is used for driving the rotating disc to rotate and driving the position of the cuboid prism to change, so that the position of the first laser and the position of the second laser incident to the first side surface are correspondingly changed, and the first laser reciprocating total optical path and the second laser reciprocating total optical path are correspondingly changed.

The invention discloses an ultrafast laser time domain shaping and calibrating device, and belongs to the field of ultrafast laser processing. Comprising a time domain shaping module and a self-correlation calibration module, the time domain shaping module splits linearly polarized ultrafast laser into a fixed light arm and a delay light arm, regulates and controls double-pulse time delay through an optical delay line, independently controls laser parameters of the two light arms, and ensures mutual orthogonality of double-pulse polarization states; the self-correlation calibration module is connected with the time domain shaping module through a coaxial optical path, converts double pulses into second harmonic (SHG) signals through an II-type phase matching nonlinear crystal, collects SHG signal intensities under different time sequences through a scanning delay line, generates an intensity self-correlation curve, calibrates a delay zero point and calculates pulse width, and the time domain shaping module is connected with the time domain shaping module through a coaxial optical path. Measurement parameters are fed back to the time domain shaping module for correcting delay parameters. The device can be applied to an existing laser processing platform, a time domain shaping double-pulse laser processing function is provided, the heat accumulation phenomenon is effectively reduced, and the ultrafast laser processing quality is improved.

The invention relates to an optical processor (2), in particular to an optical interferometer, comprising: a plurality of processor input ports (5.1 to 5.4) for receiving input optical signals (4.1 to 4.4), a plurality of processor output ports (6.1 to 6.4) for emitting output optical signals (7.1 to 7.4), and an optical network (9) that connects the processor input ports (5.1 to 5.4) to the processor output ports (6.1 to 6.4) and comprises at least one layer (11) with a plurality of optical devices (10a-c) configured to process the input optical signals (4.1 to 4.4) from the processor input ports (5.1 to 5.4). The at least one layer (11) has a plurality of input ports (14.1 to 14.4) and a plurality of output ports (15.1 to 15.4) that are connected to the plurality of input ports (14.1 to 14.4) via optical delay lines (16.1 to 16.4). The invention also relates to an apparatus (1), comprising: an optical processor (2) as indicated above, a plurality of light sources (3.1 to 3.4) for generating the plurality of input optical signals (4.1 to 4.4) for the optical processor (2), and a plurality of optical detectors (8.1 to 8.4) for detecting the output optical signals (7.1 to 7.4) from the optical processor (2).

The application discloses a super-resolution ranging method and system based on pulse modulation type laser frequency modulation continuous wave, which comprises a light source generating device, a processing device, an adjustable optical delay line, an interference device, a signal acquisition device and a data processing device; the light source generating device is used for outputting a continuous light source; the processing device is used for processing the continuous light source; the adjustable optical delay line is used for scanning and finding a peak value of a pulse autocorrelation curve; the interference device is used for dividing the continuous light source processed by the processing device into two paths to generate interference and output; the signal acquisition device is used for signal acquisition, analysis and storage; and the data processing device is used for calculating a ranging result. Compared with a conventional light frequency modulation continuous wave ranging system, the application can break through the limitation of Fourier transform spectral resolution, realize super-resolution ranging, and meanwhile, the characteristics of low detection bandwidth of the light frequency modulation continuous wave ranging system are maintained.

The application relates to the field of distributed optical fiber sensing, and discloses a high-speed chaotic Brillouin sensing device and method based on a correlation method multi-address positioning method, wherein strong periodic broadband chaotic laser is divided into two beams through a first beam splitter, one beam is used as probe light and sequentially enters a sensing optical fiber after passing through a single sideband modulator and an erbium-doped fiber amplifier; the other beam sequentially passes through an optical delay line, an erbium-doped fiber amplifier, and a second beam splitter to be divided into pump light and reference light, the pump light passes through an optical circulator and occurs stimulated Brillouin amplification with the probe light at different positions in the sensing optical fiber; the signal in the sensing optical fiber is output after passing through the optical circulator, Stokes light is filtered out by a tunable optical filter and is detected by a first photodetector, the reference light is detected by a second photodetector, a data acquisition unit collects two-way signals and sends the two-way signals to a computer for data processing; the application improves the signal-to-noise ratio of the system, widens the sensing distance, and realizes high-speed and accurate positioning of multiple sensing points.

The invention discloses a programmable optical delay line network architecture automatic generation method based on graph search and combinatorial optimization, and aims to solve the problem that the design of an optical delay line network architecture depends on artificial experience and is high in redundancy. According to the method, four types of nodes A, B, C and D and a graph model of a strict connection rule are established, topology is coded by an adjacent matrix, acyclic paths from Ai to Di of all channels are searched by utilizing DFS, and resource conflict-free cross-channel combination is carried out; under multiple checks of node degree, 0 delay path, target matching de-duplication and B node advanced constraint, a coverage target delay combination number is defined as fitness, and maximum combination coverage is realized by adopting a GA evolutionary algorithm. According to the method, the automatic search and optimization of the network topology can be realized under the given resource limitation, the delay combination coverage capability and the design efficiency are remarkably improved, and the method is suitable for the scenes of optical communication, beam forming, programmable photon processing and the like.

The invention belongs to a measurement technology, and relates to a residual stress measurement device and method, in particular to an ultrafast time resolution residual stress measurement device based on laser ultrasound and an application method of the ultrafast time resolution residual stress measurement device. The device comprises a pulse laser, a beam splitter, a laser wavelength regulator, a biaxial galvanometer, a reflector, an optical delay line, a polarization beam splitter, a quarter-wave plate and a photoelectric detector. The bandwidth of a photoelectric detector in the prior art is difficult to meet the requirement of ultra-high time resolution (10-10 s), so that the laser ultrasonic residual stress measurement precision is insufficient. According to the ultrafast time resolution high-precision residual stress measurement method based on laser ultrasound, the problem of insufficient residual stress detection precision caused by insufficient sampling rate of a photoelectric detector is avoided through the scheme setting, the picosecond-level time resolution is realized, the residual stress detection precision is remarkably improved, and the detection precision is improved. And high-precision measurement of the residual stress of the laser ultrasonic detection sample is realized.

A communication network node (100) comprising: an antenna array (104) comprising a plurality of radiating elements (106); a plurality of photodiodes (108) connected to the radiating elements; an optical delay line (110) configured to receive an optical carrier signal modulated with an RF signal; and a plurality of optical splitters (112) provided along the optical delay line, the optical splitters configured to split off portions of the optical carrier signal to form a plurality of optical output signals and to deliver the optical output signals to the photodiodes. The photodiodes are configured to recover respective portions of the RF signal from the optical output signals and to deliver said portions of the RF signal to the radiating elements. The optical delay line is configured to time delay the optical carrier signal between variable optical splitters to phase shift the RF signal.

The invention discloses a dynamic optical scanning holographic encryption system based on time-space joint imaging, which comprises a laser, a light beam emitted by the laser is divided into two light beams by a beam splitter, one transmission light beam irradiates an orbital angular momentum multiplexing hologram, and the other transmission light beam irradiates an orbital angular momentum multiplexing hologram. One beam of reflected light is transmitted to a beam combiner through a space-time coupling spring light generation module and an optical delay line module in sequence, and the other beam of reflected light is transmitted to the beam combiner through a plane mirror, an optical switch and an encryption key in sequence, so that the other beam of reflected light interferes with the time-delayed space-time coupling spring light to generate dynamic interference fringes, and the dynamic interference fringes are scanned through a Fourier transform lens and a scanner; the time-space coupling spring light generation module is used for generating time-space coupling spring light, and the optical delay line module is used for carrying out delay processing on the time-space coupling spring light and realizing accurate modulation time delay. The invention further discloses a dynamic optical scanning holographic encryption method based on time-space combined imaging.

The invention discloses a low-loss optical delay line capable of being quickly switched and an optical switch calibration regulation and control method. The plurality of ferroelectric material layer switch phase shift regions are sequentially arranged along the light propagation direction, and ferroelectric materials are arranged in the ferroelectric material layer switch phase shift regions; the low-loss waveguide layers are connected with waveguides and are connected between the adjacent ferroelectric material layer switch phase shift regions and at the tail ends of the ferroelectric material layer switch phase shift regions; the low-loss waveguide layer delay lines are connected between the adjacent ferroelectric material layer switch phase shift regions; and the interlayer vertical coupler is connected between the low-loss waveguide layer delay line / low-loss waveguide layer connection waveguide and the ferroelectric material layer switch phase shift region. According to the scheme, the problem that a traditional switchable optical delay line is difficult to achieve long delay and efficient and fast switching at the same time is solved, the calibrated switch does not need to apply energy to maintain the calibration state when used, energy consumption is reduced, and the optical delay line is expected to be applied to the fields of optical signal processing, microwave photonics, optical switching, optical caching and the like.

The invention relates to the technical field of spaceflight, and particularly provides an optical-mechanical structure motion error measurement method, device and product under microgravity. The method comprises the following steps: acquiring a pre-constructed microgravity simulation device and a measurement platform; the measuring platform is used for fixing and supporting a to-be-measured optical machine structure, and the to-be-measured optical machine structure comprises an optical delay line and a fast reflecting mirror; under the condition that the trigger signal is received, the measuring platform does free falling motion in the microgravity simulation device; after the measurement platform completes the free falling motion, motion error data of the to-be-measured optical machine structure is acquired; wherein the kinematic error data of the optical delay line represents the rotational kinematic error of the optical machine structure to be measured in three degrees of freedom and the translational kinematic error in one direction, and the kinematic error data of the fast reflecting mirror represents the translational kinematic error in three directions. According to the invention, the rotation motion error data and the translation motion error data of the to-be-tested optical machine structure are obtained by respectively measuring the motion error data of the optical delay line and the fast reflecting mirror.

A signal processing apparatus, a detection apparatus and a terminal device, which relate to the technical field of detection, and are used for reducing the cost of and space occupied by an optical delay line. The signal processing apparatus comprises a first frequency-modulated optoelectronic loop and a second frequency-modulated optoelectronic loop. The first frequency-modulated optoelectronic loop and the second frequency-modulated optoelectronic loop share a polarization control element and an optical delay line. The polarization control element outputs an optical signal in a first linear polarization state from the first frequency-modulated optoelectronic loop and an optical signal in a second linear polarization state from the second frequency-modulated optoelectronic loop to the optical delay line in orthogonal polarization directions, and outputs respective delayed optical signals to respective mixers in the form of original linear polarization states. By means of transmitting the optical signals from the two frequency-modulated optoelectronic loops in the same optical delay line, the two frequency-modulated optoelectronic loops can share the same optical delay line, thereby reducing the number of optical delay lines required to be provided in the signal processing apparatus, and reducing the cost of and space occupied by the optical delay line.

The invention discloses a time delay and gain calibration method for an optical domain simulation beamforming system, and relates to the technical field of microwaves and the field of optical communication. According to the method, a system structure is shown in a figure 1 in the specification, and the system comprises a signal source, an electric power divider, a low-noise amplifier, a directly modulated laser, an adjustable optical delay line, an adjustable optical attenuator, an optical coupler, a photoelectric detector, a frequency spectrograph and an upper computer. Signal source output is divided into N paths by an electric power divider, amplified by a low-noise amplifier and then loaded to N paths of directly modulated lasers with different optical carriers to realize electro-optical conversion, and modulated optical signals are transmitted to a delay gain control module consisting of an adjustable optical delay line and an adjustable optical attenuator through an optical fiber; the upper computer adjusts the delay and gain of the multi-path optical signals by controlling the delay gain control module, the multi-path optical signals are coupled into one path of optical signals through the optical coupler and then converted into electric signals through the photoelectric detector, and the frequency spectrograph is used for monitoring the power of the electric signals. The upper computer reads the power of the frequency spectrograph and adjusts the delay gain control module in real time so as to realize delay and gain calibration of any channel of the system, the calibration precision is high, and the operation is simple and fast.

A kind of femtosecond laser synchronization device and method based on hollow-core anti-resonant optical fiber, comprising: first mirror, second mirror, balanced optical cross correlator, first lens, first vacuum chamber, hollow-core anti-resonant optical fiber, second vacuum chamber, second lens, third mirror, fourth mirror, optical delay line and control unit;The time drift of femtosecond laser pulse is measured by balanced optical cross correlator;When balanced cross correlation signal is not zero, there is time drift between two laser pulses, and the amount of drift is indicated by the intensity of balanced cross correlation signal, and the direction of drift is indicated by the positive and negative of cross correlation signal.Correlation signal is transmitted to control unit for processing and generating control signal, and control optical delay line, and balanced optical cross correlation signal is locked to zero, that is, the long-time synchronization of two femtosecond laser pulses is realized by closed-loop feedback control.The present application realizes the long-time synchronization of two femtosecond laser pulses, and can be used in the fields of ultra-short pulse laser synchronization control, ultrafast pump-probe experimental research, etc.