55 results about "Double frequency" patented technology

The invention relates to the technical field of satellite navigation and wireless communication, and discloses an indoor positioning method and system based on feeder multiplexing Beidou double-frequency, and the method comprises the steps: receiving outdoor B1I and B2a signals through a high-gain Beidou double-frequency receiving antenna, carrying out the frequency separation and signal conditioning through a double-frequency separation filter, and carrying out the positioning of the B1I and B2a signals; and transmitting the B1I signal to an indoor distributed antenna for broadcasting through the existing communication feeder network, and transmitting the B2a signal to a central directional antenna to establish a time synchronization reference. A mobile terminal receives a dual-frequency signal, capturing and tracking are carried out through digital signal processing, and pseudo-range and carrier phase observation values are extracted. And performing pairing processing on observation data of the same antenna, calculating a dual-frequency pseudo-range difference value, eliminating system errors, and performing position calculation by adopting a weighted least square method and Kalman filtering. The method solves the problem that the traditional GPS signal cannot cover the indoor environment, and has a good application prospect in the scenes of underground commercial complexes, tunnels, parking lots and the like.

The invention relates to a double-ridge waveguide antenna array applied to satellite communication, and relates to the technical field of antennas. The antenna comprises a horn radiation layer, a waveguide transmission layer, a low-frequency feed layer and a high-frequency feed layer which are sequentially arranged in the stacking direction. The low-frequency feed layer and the high-frequency feed layer are connected with the horn radiation layer through the waveguide transmission layer and the stepped impedance conversion waveguide; the horn radiation layer comprises dual-band horn common-caliber radiation units, metal blocks and metal strips, the metal blocks and the metal strips are used for constructing ridge waveguide structures, the adjacent dual-band horn common-caliber radiation units are separated by the metal strips, and the ridge waveguide structures constructed by the metal blocks are used for loading and expanding bandwidth; according to the invention, the design complexity of double frequency bands with a large frequency ratio is effectively simplified, and the design compactness of the antenna array is improved.

The utility model belongs to the technical field of fiber lasers, and particularly relates to a high-efficiency frequency doubling system for a laser. The high-efficiency frequency doubling system for the laser comprises a first lens, a first frequency doubling crystal, a 4f system and a second frequency doubling crystal which are arranged in sequence. According to the high-efficiency frequency doubling system for the laser, the two frequency doubling crystals are used, phase matching is adopted, S polarization light and P polarization light of fundamental frequency light are subjected to frequency doubling in sequence to form P polarization frequency doubling light and S polarization frequency doubling light, two times of frequency doubling of the non-polarization-maintaining fiber laser are achieved through two times of frequency doubling, and high-power green light in the mixed polarization direction is obtained. And under the condition that the infrared fundamental frequency power is kept unchanged, the proportion of S polarization component light to P polarization component light is changed due to the change of the polarization state, but two generated green light beams are complementary, so that the power output is more stable than that of one crystal.

The invention relates to an antenna assembly and a vehicle. The antenna assembly comprises a dielectric body, a first antenna structure, a second antenna structure and a metal frame body. The projections of the plurality of second antenna structures on the dielectric body along the thickness direction of the dielectric body are arranged around the circumferential direction of the first antenna structure, the plurality of second antenna structures are rotationally symmetrical about the center of the first antenna structure, and each second antenna structure is coupled with the first antenna structure. The metal frame body is arranged around the periphery of the first antenna structure, and the metal frame body is connected with the dielectric body. The low-profile antenna structure is realized, the influence caused by the surface wave effect of the dielectric body is improved, the mutual coupling interference between double frequencies is reduced, and the antenna gain and the antenna bandwidth are improved. Besides, the metal frame body can restrain back lobe level energy, capacitance coupling is formed between the first antenna structure and the metal frame body, capacitance coupling is formed between the second antenna structure and the metal frame body, the antenna miniaturization design is further achieved, the overall size is reduced, and the installation space can be prevented from being limited.

The application discloses a high-energy and few-cycle blue light laser generation method and device, and belongs to the technical field of ultrafast laser, wherein the method comprises the following steps: adopting a nonlinear crystal to double frequency of a base frequency pulse after compression, and performing at least twice pulse width compression on the obtained double frequency pulse to obtain high-energy and few-cycle blue light laser; wherein, the double frequency process and the pulse width compression process are both performed in a cavity filled with helium; the pulse width compression process is performed through spectral broadening of a solid sheet; since the helium has extremely low linear dispersion and nonlinear coefficient and extremely high ionization energy, not only the solid sheet damage can be avoided, and a part of spectral broadening is contributed, but also an environment close to vacuum can be provided in terms of dispersion and laser-induced ionization, so that the dispersion compensation of the double frequency pulse is easier, and the energy loss caused by gas ionization and the input energy limitation are avoided, and higher output energy is allowed; the problem that the high-energy and ultra-short pulse width blue light pulse is difficult to be realized simultaneously at present is effectively solved.

1. The name of the design product: full transparent vertical double frequency anti-theft access control. 2. The use of the design product: the design product is used for attendance management, identity recognition and access control management. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

The application discloses a kind of based on decoupling surface and isolation plate's dual polarization and double frequency base station antenna and array, the base station antenna includes low frequency antenna array, high frequency antenna array, antenna floor and multiple first isolation plate being arranged in antenna floor, multiple second isolation plate being arranged in the middle of adjacent two first isolation plate;High frequency antenna array includes multiple columns of high frequency antenna unit column being installed in the middle of adjacent first isolation plate and second isolation plate;Low frequency antenna array includes multiple columns of low frequency antenna unit column being installed in the middle of adjacent two first isolation plate;Each column of low frequency antenna unit column includes multiple low frequency antenna units printed with decoupling surface, decoupling surface includes 8 several Chinese character shape metal strip, 180 square metal patch and 40 rectangular metal patch.Not only solve the problem of low frequency antenna to high frequency antenna's shelter, repair high frequency antenna pattern, but also can effectively improve low frequency antenna and high frequency antenna's same frequency isolation, improve decoupling effect.

The application discloses a polarization converter using terminated filter circuit to control frequency characteristics, comprising: a dual-polarized antenna array and a filter circuit arranged on the back of the antenna array floor, the dual-polarized antenna array is used for transmitting the received electromagnetic wave signal to the filter circuit arranged on the back of the antenna array floor, and transmitting the signal output through the filter circuit to the free space; the filter circuit is used for realizing the control on the frequency characteristics of the polarization converter. By arranging different filter circuits on the back of the antenna array floor, the polarization converter with different frequency characteristics can be obtained. The application designs a reflection type polarization converter with super wideband and double frequency band. When linear x-polarized or y-polarized electromagnetic wave irradiates to the surface of the polarization converter, the reflected wave is the orthogonal polarization thereof. The application can be used for antenna design, radar cross section (RCS) reduction and wireless communication technology.

The application discloses a kind of triaxial SERF atom magnetometer quadrature double frequency modulation system and method, the system utilizes signal generation module to generate frequency f m The sine quadrature modulation signal of cosine is respectively driven SERF atom magnetometer X and Y axis magnetic field generating coil, and 2nf m Frequency sine signal of driving Z axis coil, through the integral filter of 3 groups of integral period integration, the open-loop magnetic field signal of X axis, Y axis and Z axis magnetic field component is obtained, and through control module, the driving current of three-axis magnetic field coil is controlled to generate compensation magnetic field, so that the open-loop magnetic field signal of X axis, Y axis and Z axis magnetic field component is zero, at this time, the magnetic field intensity of atom chamber is zero, and the compensation current output by control module is the X, Y and Z axis magnetic field intensity signal measured by triaxial SERF atom magnetometer.The system can directly extract triaxial magnetic field calculation signal from a laser signal, and eliminate the cross-coupling effect when triaxial magnetic field is calculated, improve the measurement range and quadrature of SERF atom magnetometer, with very high engineering application value.

The application provides a time-frequency offset estimation method and device of an LTE system, and relates to the technical field of communication. The method comprises the following steps: a plurality of decimal multiple frequency offsets are used to compensate the initial received signal to obtain a first target signal; after PSS detection and screening of the first target signal, the first m first correlation peak values in descending order, N-ID-2 corresponding to the first correlation peak values, the first timing position and the first frequency offset value are obtained; a plurality of integer multiple frequency offsets are preset and the second correlation peak values corresponding to each first correlation peak value are calculated; the time domain position of each second correlation peak value is located and frequency offset compensation is performed to obtain a second target signal; after SSS detection and screening of the second target signal, the first n second correlation peak values in descending order, N-ID-1 corresponding to the second correlation peak values, the second timing position and the second frequency offset value are obtained, and the cell ID is obtained by combining N-ID-1 and N-ID-2. The application separates the decimal multiple frequency estimation and the integer multiple frequency offset estimation, and the double frequency offset estimation improves the accuracy.

The application relates to the technical field of signal processing, and provides a signal processing method and system of a rubidium atomic frequency standard, a main frequency standard adopts a double-threshold amplitude comparison circuit, a standby frequency standard adopts a single-threshold amplitude comparison circuit, and the existence of a signal, the validity of an amplitude and a locking state are synchronously monitored; double-threshold detection of the main frequency standard ensures reliability, single-threshold detection of the standby frequency standard ensures readiness for quick switching, and the reliability and switching efficiency are balanced; through preset logic rule fusion analysis, the validity is comprehensively judged in combination with a frequency standard locking signal. A control signal is generated based on a priority rule, the main frequency standard is kept when the main frequency standard is valid, a high-level pulse synchronized with a 10MHz signal zero-crossing point is generated when the main frequency standard is invalid and the standby is ready, an abnormal alarm is triggered when the double frequency standards fail, and the control signal is transmitted to a frequency standard switching circuit through a level conversion subunit, so that the trigger timing requirement of a high-speed switching module is met, quick response switching is ensured, the stability in the switching process is ensured, and the whole is reliable and stable.

This invention discloses an adaptive dual-mode direction backtracking system based on double frequency conversion, comprising a radio frequency (RF) circuit, a control circuit, a local oscillator (LOO), and an antenna array. The RF circuit amplifies, filters, and mixes the RF signals received by the antenna array to form signal transmission links in mixed-mode and Van Atta array modes. The control circuit provides unified control over the RF switches and the transmit / receive delays of each channel, and outputs control signals according to the operating mode switching requirements. The LEO generates and distributes a fixed LEO signal and an adaptive LEO signal to achieve frequency matching under different incoming wave frequencies. The antenna array receives external incoming wave signals and transmits direction backtracking signals, employing an adjacent transceiver unit interconnection method in mixed-mode and a centrally symmetrical array element interconnection method in Van Atta array mode. This invention enables stable direction backtracking under different incoming wave frequencies and different application scenarios.

The invention relates to an energy storage converter harmonic wave and double frequency suppression method. By sampling the inductive current output by the DC / AC converter, dead time compensation is carried out, low-order harmonics in the output voltage can be reduced, and the quality of output electric energy is improved. Band elimination filtering is performed on voltage sampling feedback of the DC / DC converter, so that the output DC capacitor of the DC / DC converter bears frequency doubling power, the power fluctuation of an energy storage element is reduced, the service life of the energy storage element can be prolonged, the loss of the energy storage converter is reduced, and the performance and the power density of the energy storage converter are improved.

The present application relates to a kind of large specification 86CrMoV7 steel kind embossing roller processing technology, roller body processing method: roller body quenching and tempering piece-frame position-rough boring inner hole-half precision turning-outer circle grinding-magnetic exploration-double frequency quenching+tempering-precision turning frame position-precision boring inner hole-precision turning and shaft head hot mounting;Shaft head processing method: shaft head quenching and tempering piece-precision turning and roller body hot mounting.Processing method is adopted after roller body hollow double frequency quenching and then hot mounting, selects reasonable process parameter, solves the precision control problem of fit length and total length, avoids the quality problems such as quenching crack, deformation, uneven hardness easily appeared in hollow double frequency quenching process, effectively guarantees product quality, satisfies user demand.

The application relates to a group velocity mismatch-based closed defect reference-free positioning method and system, which comprises the following steps: acquiring attribute information of a sample to be tested, determining ultrasonic excitation parameters based on the attribute information; generating an ultrasonic signal based on the ultrasonic excitation parameters, and propagating into one end of the sample to be tested; receiving a receiving signal generated at the other end of the sample to be tested; performing time-frequency analysis on the receiving signal to determine whether a fundamental frequency signal and a double frequency signal exist simultaneously, if yes, extracting peak times of the fundamental frequency signal and the double frequency signal, and if no, determining that there is no closed defect; and determining the position of the closed defect in the sample to be tested based on the peak times and a group velocity curve of the sample to be tested. Compared with the prior art, the application can reference-free identify and position the closed defect by using the contact acoustic nonlinear effect of the closed defect without damaging the sample to be tested, and has the advantages of fast detection, high defect positioning accuracy and the like.

The embodiment of the invention provides a single-point time service method and device for a receiver, the receiver and a storage medium thereof, and relates to the technical field of satellite positioning time service. The method comprises the following steps: acquiring historical parameter value vectors and historical covariance vectors of a plurality of undetermined parameters in non-difference and non-combination PPP model linearization observation equations of a plurality of satellites and receivers, the plurality of undetermined parameters comprise receiver clock errors of different types of satellites, troposphere time delays of the satellites, receiver orientations and space signal ranging errors; acquiring satellite observed quantities of a plurality of satellites at double frequency points in a standard single-point mode; obtaining a current parameter value vector and a current covariance vector through a Kalman filtering algorithm according to the satellite observed quantity, the historical parameter value vector and the historical covariance vector; and determining and determining a target clock error for time service according to the satellite observed quantity of the target satellite, the troposphere time delay of the target satellite in the current parameter value vector and the current position of the receiver, thereby realizing precise time service.

The application relates to the technical field of signal processing, and provides a signal processing method and system of a rubidium atomic frequency standard, a main frequency standard adopts a double-threshold amplitude comparison circuit, a standby frequency standard adopts a single-threshold amplitude comparison circuit, and the existence of a signal, the validity of an amplitude and a locking state are synchronously monitored; double-threshold detection of the main frequency standard ensures reliability, single-threshold detection of the standby frequency standard ensures readiness for quick switching, and the reliability and switching efficiency are balanced; through preset logic rule fusion analysis, the validity is comprehensively judged in combination with a frequency standard locking signal. A control signal is generated based on a priority rule, the main frequency standard is kept when the main frequency standard is valid, a high-level pulse synchronized with a 10MHz signal zero-crossing point is generated when the main frequency standard is invalid and the standby is ready, an abnormal alarm is triggered when the double frequency standards fail, and the control signal is transmitted to a frequency standard switching circuit through a level conversion subunit, so that the trigger timing requirement of a high-speed switching module is met, quick response switching is ensured, the stability in the switching process is ensured, and the whole is reliable and stable.

The invention discloses a double-frequency phased array composite pulse histotripsy system and a double-frequency phased array composite pulse histotripsy method. Comprising a double-frequency phased array transducer, a driving control module, a focus control module and a real-time monitoring module, wherein the double-frequency phased array transducer is a double-frequency hundreds of array element phased array transducer or a double-frequency split array transducer; the double frequency multiplication phased array transducer comprises a fundamental frequency array element group and a frequency multiplication array element group, the driving control module is used for outputting driving signals with corresponding frequencies to two groups of array elements, the focus control module is used for regulating and controlling the positions and the number of focuses, and the real-time monitoring module is used for tracking the effect; the double-frequency phased array composite pulse histotripsy system adopts a four-stage composite pulse time sequence to cooperatively control the working states of a fundamental frequency array element group and a frequency multiplication array element group, and is realized in combination with a multi-focus control strategy; according to the method, the defect of fogging zone front cavitation shielding possibly caused by double-frequency millisecond long-pulse tissue damage and the defect that instant B-ultrasonic monitoring is affected by slow bubble dissipation after treatment are overcome.

An underground buried object detection sensor based on metamaterial resonance is mainly composed of three layers which are a metal grounding layer, a dielectric layer and a metal patch layer from bottom to top. Two complementary slotted metal rings (CSRR) are etched on a metal grounding layer, and a metal patch layer is formed by combining a circular ring and two microstrip lines. The sensor can achieve the purpose of detecting the dielectric constant of the dielectric plate in different detection modes in double frequency bands. In other words, the detection of the dielectric constant is realized by monitoring the amplitude change in the frequency band of 1.25-2.00 GHz, and the detection sensitivity is 2.10 dB / permittivity unit; the detection of the dielectric constant is realized by monitoring the frequency change in the frequency band of 2.00 to 3.00 GHz, and the detection sensitivity of the dielectric constant sensor is 39.8 MHz / permittivity unit. The method has the characteristics of high sensitivity, dual-band detection and dual detection modes, and has potential application prospects in buried target detection.

The utility model relates to a high-integration-level KuKa double-frequency time-sharing up-conversion power amplifier device, which comprises a common intermediate frequency input and switching module used for time-sharing switching of intermediate frequency signals of Ku / Ka channels; the time-sharing frequency conversion processing module is used for realizing Ku single frequency conversion and Ka double frequency conversion; the high-power GaN amplification module is used for supporting Ku and Ka frequency band power amplification respectively; and the deep sharing subsystem comprises a shared local oscillation source generation unit, an intelligent power distribution module for time-sharing power supply, an integrated radiator and an MCU (Microprogrammed Control Unit) control unit. High integration of a double-frequency function is realized by sharing an intermediate-frequency link, time-sharing frequency conversion and sharing a subsystem. Through time-sharing power supply and intermediate-frequency switching, dual-band multiplexing of an intermediate-frequency link, a reference source and a heat dissipation system is realized, a subverted split structure is adopted, a single device realizes a dual-frequency function, and compared with a traditional split scheme, the device size is reduced by 40%, the weight is reduced by 35%, and the hardware cost is reduced by 30%. The spectrum expansibility is high, and the design of twice frequency conversion and LO3 adjustability supports three-segment seamless coverage of the Ka frequency band.

The invention belongs to the technical field of ship medium-voltage power grid parameter measurement, and discloses a ship medium-voltage power grid ground capacitance measurement method based on a high and low frequency method, which comprises the following steps: constructing a ship medium-voltage power distribution network model with a neutral point high-resistance grounding, and analyzing component parameters under the condition that high and low frequencies are injected into a power grid by utilizing a circuit theory; and deducing a related parameter expression. A high-frequency and low-frequency frequency selection scheme of an improved double-frequency method is researched in a simulation comparison mode, and low-frequency and high-frequency signals for signal injection are determined by analyzing amplitude-frequency characteristics corresponding to parameters of each device according to signals with different injection frequencies. Based on a simulation model, a scaling experiment platform is constructed, signals with different frequencies are injected by using a signal generator, sampling and analysis of parameters are realized by using an oscilloscope, and measurement of the ground capacitance of the power grid is realized. According to the invention, on-line measurement of the ground capacitance of the system can be realized more accurately under the condition that the capacitance value of the medium-voltage power system of the large ship is large.

A notebook computer antenna module for carrier aggregation technology is disposed in a housing above a display of a notebook computer and includes a low frequency portion, an excitation portion, a high frequency portion, a triple frequency portion, a double frequency portion, and a carrier. The low frequency portion has a main path and a switching portion. The main path has a first end, a second end, and two ground segments, both of which are connected between the first end and a module ground, and the second end is floating. The switching portion is connected between the main path and the module ground, and the switching portion conducts one of a plurality of ground paths to change the equivalent ground length of the low frequency portion. The high frequency portion is connected above the excitation portion. The triple frequency portion is connected above the high frequency portion and coupled to the main path. The double frequency portion is connected to the module ground and coupled to the main path and the triple frequency portion. The main path of the low frequency portion obtains electromagnetic energy of the excitation portion by coupling the triple frequency portion. The present application reduces the impact on the antenna efficiency for 1710-2690 MHz when the equivalent ground length of the low frequency portion changes, to meet the carrier aggregation use.

The application discloses a single-phase phase-locked loop capable of eliminating the influence of double frequency, which comprises a double frequency elimination frequency discrimination module and a phase angle estimation module. The double frequency elimination frequency discrimination module generates a frequency discrimination signal without the influence of double frequency through mathematical processing, and then inputs the frequency discrimination signal into the phase angle estimation module with PI control and integrator, so that the real-time phase angle of the phase-locked loop is estimated by the phase angle estimation module. The phase-locked loop of the application is designed with the frequency discrimination module and the phase angle estimation module, so that the influence of the double frequency component on the phase-locked result in the steady state of the phase-locked loop is eliminated, and meanwhile, the dynamic response performance of the phase-locked loop is ensured. The application is used for online accurate estimation under non-ideal power grid conditions.

The invention discloses an electric energy meter and terminal relay contact online monitoring device and method based on a double-frequency difference method, and relates to the technical field of electrical variable measurement. The device comprises a high-frequency constant-current source, a power-frequency current acquisition module, a voltage acquisition module, a separation module and a calculation and judgment module, power-frequency current and constant high-frequency current are injected into a line section where a relay contact is located at the same time, mixed voltage is acquired, and power-frequency and high-frequency components are separated; calculating power frequency impedance and high frequency impedance respectively, and then solving a module value of a difference value of the two; the method comprises an injection step, a collection step, a separation step, a calculation step and a judgment step. Parameter interference such as line inherent resistance is counteracted by calculating the double-frequency impedance difference value, the difference value module value is only related to the contact resistance and the contact capacitance of the contact, online, real-time and quantitative monitoring of the contact state of the relay contact is achieved, and early degradation faults such as contact oxidation and abrasion can be accurately recognized.

The application designs a Coriolis mass flowmeter signal processing method based on orthogonal demodulation; an orthogonal demodulation method CH-QD based on correlation operation and Hilbert transform is proposed, first, autocorrelation operation is carried out on any one sensor signal, and the obtained autocorrelation signal is used as the same frequency cosine reference signal of the sensor signal; the autocorrelation signal is subjected to Hilbert transform, and the obtained Hilbert transform signal is used as the same frequency sine reference signal of the sensor signal; according to the same frequency and orthogonal relationship between the autocorrelation signal and the Hilbert transform signal thereof, the instantaneous frequency of the signal is calculated by complex number and trigonometric function operation; the two sensor signals are respectively subjected to sine and cosine reference signal demodulation, the center frequency of the signal is moved to the double frequency of the original frequency, and the low frequency component carrying the signal phase information is contained in the signal; the high frequency component is filtered out through a multi-stage low pass filter, and the low frequency component is retained; the low frequency component is used to extract the phase difference of the two signals, and the high-precision density, mass flow and other information of the fluid are provided.

The invention provides a signal pre-distortion processing method and device, electronic equipment and a computer program product. The signal pre-distortion processing method comprises the steps that at least two paths of initial input signals and corresponding initial feedback signals are collected; respectively combining the at least two paths of initial input signals and the corresponding initial feedback signals to generate a first input signal and a first feedback signal; performing segmentation processing on the first input signal based on the amplitude information of the first feedback signal, and determining a pre-distortion parameter; and performing pre-distortion processing on the first input signal based on the pre-distortion parameter. According to the invention, after the signals of the plurality of frequency bands are combined, the pre-distortion processing can be carried out on a unified signal, so that the complexity of the pre-distortion processing is reduced, and the calculation amount is reduced; and secondly, pre-distortion processing is performed according to non-uniform segmentation of the signal amplitude, so that the problem of poor pre-distortion effect caused by self-nonlinearity and intermodulation nonlinearity after the dual-frequency signal is changed into a large broadband is avoided.

The application discloses a kind of ultra-low profile high-gain circularly polarized folded transmission array antennas with low radar scattering cross section, including the chessboard type arrangement of PCM array, transmission array, reflecting array and feed horn;The chessboard type arrangement of PCM array is placed on transmission array, and the two are separated by air layer 1;The transmission array is placed on reflecting array, and the two are separated by air layer 2;The reflecting array center opens a rectangular hole, and the feed horn is placed in the rectangular hole and embedded.The folded transmission array antenna of the application has the wideband high-gain circularly polarized radiation performance, and the radar scattering cross section reduction of out-of-band double frequency.

The present application relates to copper rod detection technical field, especially in kind of copper rod grain size detection method and system based on double frequency eddy current analysis, method includes: according to the synchronous acquisition of high frequency eddy current response signal and low frequency eddy current response signal of copper rod surface in motion according to the orthogonal arrangement double frequency eddy current probe, and real-time acquisition copper rod movement speed;High frequency eddy current response signal and low frequency eddy current response signal are phase demodulated respectively to obtain first phase angle and second phase angle;The instantaneous difference of first phase angle and second phase angle is calculated, and the original phase difference characteristic quantity is generated;The original phase difference characteristic quantity is compensated dynamically based on copper rod movement speed, and the speed compensation phase difference characteristic quantity is generated;The speed compensation phase difference characteristic quantity is input into the pre-labeled grain size mapping relationship model, and the real-time grain size grade value is obtained.Through the present application, the eddy current response interference caused by speed change is effectively eliminated in the continuous movement process of copper rod, and the high-precision detection of grain size grade is realized.

The application provides a terahertz fundamental frequency and double frequency cooperative phase modulation super surface, device and system, relates to the generation and phase modulation technical field of terahertz waves, and the super surface comprises: a plurality of structure units, each structure unit is arranged on the same two-dimensional plane in a two-dimensional arrangement manner;The rotation angles of each structure unit relative to the same reference direction in the two-dimensional plane are not all the same;When the structure unit is subjected to circularly polarized terahertz wave incidence, the transmission end of the structure unit outputs terahertz waves comprising at least a fundamental frequency component and a second harmonic component, and the phases of the terahertz waves output by the structure units with different rotation angles are different.In the same super surface, a fundamental frequency signal with a frequency of a fundamental frequency and a second harmonic signal with a frequency of twice the fundamental frequency are generated, and the phases of the output terahertz waves are different by setting structure units with different rotation angles, so that the phase of the terahertz wave can be modulated while the frequency of the terahertz wave is doubled.

1. The name of the design product: optical fiber machine (double frequency 1.3). 2. The use of the design product: for optical fiber communication transmission. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view.