375 results about "Fixed frequency" patented technology

The invention relates to a reconfigurable dual-mode leaky-wave antenna with global scanning capability and a reconfiguration method, the leaky-wave antenna comprises a double-layer slow-wave waveguide structure formed by an upper metal conductor and a lower metal conductor, and the upper metal conductor and the lower metal conductor are separated by a dielectric substrate; the double-layer slow-wave waveguide structure comprises a plurality of periodic units, and a plurality of T-shaped structures with opposite directions are processed on upper and lower layers of metal conductors of each periodic unit to form a plurality of grooves; a variable capacitance diode is embedded into the tail end of a slot arm of the upper-layer metal conductor and is electrically connected with the lower-layer metal conductor through a metal via hole, and a closed loop is formed between the upper-layer metal conductor and the lower-layer metal conductor; a plurality of elliptical radiation patches are arranged at the top of a slot arm of the lower metal conductor at intervals and used for radiation leakage of the slow wave waveguide, and continuous frequency scanning covering 180 degrees is achieved; according to the invention, two modes of frequency scanning and fixed-frequency scanning are fused, 180-degree global scanning can be realized in any frequency reconfigurable interval, and beams can be flexibly reconstructed through multiple control strategies under a fixed-frequency condition.

The invention discloses a signal reconnaissance, positioning and interference method based on deep learning, and belongs to the technical field of electronic countermeasures. The method comprises the following steps: deploying distributed reconnaissance nodes to obtain broadband electromagnetic signals; generating a spectrogram through time-frequency transformation, and identifying a fixed frequency / frequency hopping signal based on a deep learning model; fusing multi-node reconnaissance results to realize target situation awareness; the optimal positioning cluster is selected through dynamic networking, and the target position is calculated in combination with the arrival angle and time difference information; generating an optimal interference strategy based on the target situation and the position trajectory; networking cooperative interference is implemented; behavior parameters are collected in real time, the interference effect is evaluated through a machine learning model, and the strategy is dynamically adjusted. According to the method, the technical effects of high-efficiency and self-adaptive signal reconnaissance, positioning and interference in a complex electromagnetic environment are achieved.

The invention discloses a household electrical appliance fault diagnosis system based on artificial intelligence, and relates to the technical field of household electrical appliance fault diagnosis and state monitoring. Working condition parameters aligned with a time window are obtained through working condition sensing, and fault features and the working condition parameters are linked in an order form to be converted into a target frequency track; fault characterization is converted into track characterization capable of being continuously tracked along with working conditions from a fixed frequency point, and disturbance to fault positioning in the speed change process is reduced; in order to solve the problem that weak fault components are covered by the same frequency band due to strong dynamic background noise jointly formed by inverter switch harmonic waves, current harmonic waves and load fluctuation, a dynamic noise reference spectrum is output under the current working condition through a condition generation model, and a current spectrum and the dynamic noise reference spectrum form a residual spectrum; the background spectrum base related to the working condition is suppressed, and the separability of the weak fault component in the residual domain is improved from the source.

The invention relates to the technical field of refrigeration house unit control, in particular to a frequency conversion-fixed frequency refrigeration house unit control method based on cooperative control. The method comprises the following steps: establishing a control basis through system initialization and parameter setting, acquiring multi-dimensional data such as temperature in a library, compressor current and door state, and packaging the multi-dimensional data into a system real-time state data packet; performing verification filtering processing on the acquired data to generate a filtering temperature value and a safety state identifier; the real-time temperature difference and the change trend are analyzed based on the temperature data, the load state is determined through a load evaluation model, an inverter compressor independent operation mode or a variable frequency-fixed frequency compressor cooperative operation mode is intelligently selected, and operation parameters are dynamically optimized; and corresponding energy-saving and protection strategies including condensation fan adjustment, heat recovery management, door state linkage control and time-of-use electricity price response are executed according to the operation mode. According to the control method, the defects of a traditional control method in the aspects of energy efficiency and stability are overcome, and intelligent management and energy-saving optimization of the refrigeration house unit are achieved.

The invention discloses a robot remote adaptive data acquisition control system and method based on dynamic value evaluation. According to the system, dynamic information value factors of data points are calculated in real time through a local processing unit of the robot, and the factors integrate the data change rate, the uncertainty, the task context and the abnormal probability. Based on the factor, the system dynamically adjusts the sampling frequency, the compression strategy and the transmission priority. The remote center is responsible for data reconstruction and fusion and utilizes machine learning closed-loop optimization to acquire parameters. According to the invention, the problems of resource waste and key information acquisition omission caused by fixed frequency sampling are solved, and the optimal balance of data acquisition efficiency and quality under a limited bandwidth is realized.

The invention discloses a multi-port DAB energy storage system directly connected with an elevator frequency converter bus and a cooperative control method of the multi-port DAB energy storage system, and is suitable for an elevator frequency converter direct-current bus direct-connection scene. Aiming at the defects in the aspects of elevator bus transient support, multi-branch extension and parallel operation safety access in the prior art, at least two DAB power branches are adopted, the low-voltage sides of the DAB power branches are connected into the same low-voltage direct-current source in parallel to realize current expansion, and the high-voltage sides of the DAB power branches are connected to a VFD direct-current bus through a parallel operation access switch to realize voltage expansion after being connected in series and laminated; the controller adopts fixed frequency phase shift control, and combines a two-line parallel operation or power-off time sequence and a zero-crossing residence strategy; through multi-branch phase interleaving, mutual exclusion amplitude limiting constraint, ZVS guarantee and a fault striding linkage mechanism, branch power balance, circulating current suppression and bus stable support are realized. According to the invention, the millisecond voltage of the bus can be efficiently suppressed, the response speed, the operation efficiency and the reliability of the system are improved, and the core requirements of elevator bus energy recovery and transient stability control are met.

The invention relates to the technical field of power equipment state detection, in particular to a transformer winding state detection method, system and equipment based on dynamic frequency band adaptation and a storage medium. Collecting full-band frequency response data of the healthy reference winding, and performing adaptive adjustment on a preset basic frequency band based on the peak-valley distribution density to obtain a reference target frequency band matched with the frequency spectrum characteristics of the winding; generating a reference polar coordinate feature map through a phase-amplitude mapping rule, and extracting pattern texture features to construct a reference feature library; collecting detected winding data and taking the reference target frequency band as a detection frequency band to generate a detected polar coordinate feature map; a multi-dimensional evaluation result is obtained through graph space similarity comparison and feature difference quantification in combination with amplitude anomaly recognition; and outputting a normal, slight fault or serious fault state judgment result of the tested winding based on the preset evaluation threshold interval and the working condition adaptation correction rule. The problems that in the prior art, frequency band division is fixed, and threshold values lack working condition adaptation are solved.

A fabricated building construction monitoring method belongs to the technical field of buildings, and comprises the following steps: comparing temperature and humidity, wind speed and displacement values with preset thresholds, judging whether to calculate the reading fluctuation amplitude of a strain sensor, generating a sensitivity calibration value when the reading fluctuation amplitude exceeds a reference range, and calculating the temperature and humidity change rate based on the scanning of the coordinates of a key bearing member. And optimizing a transmission interval according to a standard rate threshold value, analyzing a construction stage coding reconstruction pressure threshold value interval, and generating a positioning early warning alarm instruction by integrating a dynamic pressure threshold value, a key area identifier, a connection node stress value, a wind speed value and a displacement value. The method has the advantages that data are read in real time and compared with a preset threshold value, whether high-frequency sampling is started or not is judged, a refined monitoring mechanism is triggered according to environmental conditions, strain data fluctuation can be captured in time in adverse environments such as high temperature and low humidity, and missing detection of abnormal working conditions caused by conventional fixed-frequency monitoring is avoided.

The invention relates to the technical field of diaphragm pump aging test, and discloses a two-parameter intelligent closed-loop diaphragm pump aging test system and method. According to the method, a temperature spectrum and a vibration spectrum are obtained through fast Fourier transform, a frequency domain coherence coefficient is calculated to identify temperature-vibration coupling characteristics, a resonance frequency band and a drift trend thereof are identified in real time by adopting a spectrum peak tracking algorithm, and a multi-objective optimization function considering aging acceleration efficiency and resonance risk is constructed. And solving the optimal temperature stress amplitude and vibration stress frequency by using a particle swarm algorithm, generating a stress loading instruction avoiding a resonance area through a self-adaptive PID controller, and dynamically updating model parameters based on a closed-loop feedback mechanism. According to the invention, the problem of resonance effect amplification caused by traditional fixed frequency stress loading is solved, and refined adaptive stress control is realized.

The invention provides a force direction feedback system and method of pneumatic pressure. The system generates a first oscillation signal changing along with air pressure and a second oscillation signal with fixed frequency through a signal conversion module; and the counter counts the cycles of the two paths of oscillation signals. The back noise calibration module samples environment back noise by using a second oscillation signal in a frequency division manner, and eliminates back noise interference in a force count value through a subtractor, so that the problem of detection deviation caused by environment air pressure fluctuation is solved; and the dual-threshold comparison module screens the difference signal through a back noise threshold and an anti-shake threshold, generates a force conversion value, and avoids error output caused by slight fluctuation and shake. The differential operation module processes the force conversion value in combination with the second oscillation signal, the accurate pneumatic force value is output through signal correlation, the pneumatic direction can be distinguished by means of comparison with the fixed reference, and finally accurate and stable feedback of the pneumatic pressure force and direction is achieved.

The invention discloses an electrically-controlled beam scanning leaky-wave antenna and communication equipment, belongs to the technical field of antennas, and is used for solving the problems that an existing antenna is complex in structure and the beam scanning angle is limited under a fixed frequency. The electrically controlled beam scanning leaky-wave antenna comprises a gap waveguide and a plurality of radiation units. The gap waveguide comprises a cover plate and a metal bottom plate which are oppositely arranged, and a ridge structure arranged on the upper surface of the metal bottom plate in the transmission direction of the electromagnetic waves, and the gap waveguide is used for transmitting the electromagnetic waves in a traveling wave mode; the plurality of radiation units are sequentially arranged on the cover plate along the extension direction of the ridge structure; each radiation unit comprises a radiation patch, two radiation slots and two electric control switches which are sequentially arranged from top to bottom, and the radiation slots and the electric control switches are distributed in a central symmetry manner relative to the radiation patch; and each electric control switch is used for controlling the working state of the corresponding radiation slot so as to regulate and control the radiation phase of the radiation unit and realize beam scanning.

The invention relates to the technical field of data acquisition, and discloses a low-power-consumption edge calculation outdoor energy storage power supply data acquisition system, which comprises a data analysis unit, a collaborative analysis unit, a probability analysis unit and an acquisition correction unit, and is characterized in that the data analysis unit, the collaborative analysis unit, the probability analysis unit and the acquisition correction unit are combined for analysis; intelligent dynamic regulation and control of outdoor energy storage power supply data acquisition are realized, the defect of data delay under low temperature and high load in a traditional fixed frequency acquisition mode is overcome, the data acquisition effect is ensured, low power consumption is ensured, meanwhile, the real-time recognition capability of hidden dangers such as over-discharge and internal resistance abnormity is improved, and the real-time recognition capability of the hidden dangers such as over-discharge and internal resistance abnormity is improved. And the cycle service life of the battery is effectively prolonged.

According to the intelligent inclinometry monitoring system and method, the sensor configuration process is simplified, batch management of sensor address IDs is achieved through a clear key and a registration key of an edge node, the address IDs of a plurality of inclination sensors are configured in sequence through one key, the configuration workload of technicians is greatly reduced through the design, and project progress delay is avoided. The edge nodes are in wireless communication with the cloud server through the 4G module, complex line wiring is not needed, occupation of monitoring space is reduced, and coordinate measurement errors caused by line interference are reduced. A multi-mode data sampling mechanism is set through a cloud server, wherein three modes of fixed sampling (collection according to a fixed frequency), roll-call collection (collection by a specified sensor) and continuous collection (high-frequency collection in batches) are supported; the edge nodes flexibly collect data based on a mechanism issued by the cloud server, invalid data redundancy is avoided, and collection pertinence and efficiency are improved. The automatic and intelligent level of deep soil displacement is remarkably improved.

The invention provides a group compaction operation-oriented master-slave cooperation space-time planning control method. The method comprises the following steps of 1, determining a construction region boundary and performing equal-area grid division; 2, a road roller starting path is generated through a third-order Bezier curve and curvature constraint, and each road roller generates a local path to the starting point of the target operation area according to the initial position of the road roller; 3, performing multi-machine path coordination based on space-time constraint, performing speed assignment on each point after each road roller completes local path planning from the current position to the starting point of the target area, and calculating expected time required by path completion; 4, a real-time state synchronization and safety protection mechanism is established, all the road rollers broadcast self position information at a fixed frequency in the operation process, the real-time distance between every two road rollers (i, j) is calculated, and the safety distance is set; and the collision between the two road rollers is avoided by judging the real-time distance and the safe distance.

The invention discloses a VR scene control method and system, and belongs to the technical field of VR scene control, and the method specifically comprises the steps: deploying a global time controller, generating a continuously increasing global timestamp at a fixed frequency, and transmitting the global timestamp to a scene rendering, audio processing and touch driving module; the scene interaction monitoring unit continuously collects user body movement and virtual object movement state data, analyzes interaction event types and characteristic parameters and then binds the interaction event types and the characteristic parameters with a current global timestamp to form an interaction information packet with the timestamp; a multi-modal feedback instruction generation unit receives the information packet, and generates three types of instructions carrying the same global timestamp based on the interaction event type, the characteristic parameters and the bound global timestamp; the feedback instruction distribution unit forwards the three types of instructions to corresponding modules at corresponding moments according to global timestamps carried by the instructions; and after executing feedback, each module records delay and sends the delay to the global time controller, so that the actual execution moments of three types of instructions in the next round are consistent.

The invention relates to the field of sewage treatment, and provides an automatic start-stop regulation and control method for multiple sets of water treatment equipment, which comprises the following steps: calculating the number of fixed-frequency lifting pumps needing to be regulated in k cycles; calculating the frequency of the variable frequency lift pump in the k period by using a BP-pid algorithm, and calculating a weighting coefficient of the k + 1 period; according to the frequency of the variable-frequency lifting pump, the operation time of the variable-frequency lifting pump and the actual liquid level of the storage pond, the accurate number of the fixed-frequency lifting pumps needing to be adjusted in the k period is obtained through correction; and the number of the fixed-frequency lifting pumps needing to operate in the k period is determined. The problem that in the prior art, starting and stopping of the lifting pump are controlled through segmented liquid levels, so that acceleration equipment losses are caused is solved, and the intelligent control efficiency of the storage pond lifting pump system is remarkably improved.

The embodiment of the specification discloses an interaction method of a wearable device, the wearable device applied by the method comprises an image sensor and an audio sensor, each environment memory unit is obtained at a fixed frequency by analyzing and processing video data continuously collected by the image sensor. Then, in response to the interaction request of the user, a serialized to-be-executed subtask and an input resource label required for the execution of the subtask can be planned. According to the execution order, at least one of historical data in the environment memory unit and current sensor-collected perception data is scheduled according to the input resource label for each subtask in sequence to execute the subtask. Finally, natural language description response information is generated based on the execution result after the execution of each subtask is completed. By constructing the time-sequenced environment memory unit, the problem caused by the lack of continuous perception and memory capability is solved, the multi-modal information collaborative reasoning is supported by the label-driven resource scheduling, and the flexible execution of the task is realized.

The invention relates to a slab crystallizer corner hanging steel detection method comprising the following steps: S1, arranging temperature measurement columns on two sides of four corners of a crystallizer, and arranging a plurality of temperature measurement points in each temperature measurement column; s2, collecting the temperature of the temperature measuring point at a fixed frequency; s3, for each temperature measurement column, constructing a fitting model by using the temperature and the position of the selected temperature measurement point in the temperature measurement column, and calculating the heat storage capacity of the temperature measurement column by using a temperature distribution function constructed by the fitting model; s4, calculating the heat storage capacity of the corner by using the heat storage capacity of the temperature measurement columns on the two sides of the corner; s5, making a two-dimensional coordinate system by taking the center of the section of the crystallizer as an original point, associating the two centrosymmetric corners, calculating the heat storage quantity difference of the associated corners, constructing a vector component corresponding to the heat storage quantity difference in the two-dimensional coordinate system, constructing a partial vector according to the vector component, performing matrix mapping to obtain the partial vector, and calculating the heat storage quantity difference of the associated corners; and judging the angle steel hanging condition according to the die length and the vector angle theta. According to the method, thermal anomaly and change of a crystallizer corner area are used as corner suspension breakout early warning criteria.

The invention discloses a nonlinear support system and a hypersonic velocity sweep / fixed frequency wind tunnel test method, and belongs to the technical field of wind tunnel tests. The device comprises a protection platform, a protection cover, a lifting platform, a vertical mounting plate, a protection cover shoulder split, a test model and a driving mechanism, the test model is mounted at the top of the vertical mounting plate through the driving mechanism, the vertical mounting plate is mounted on the lifting platform, the protection cover is mounted on the protection platform, and the protection cover shoulder split is arranged at the top of the protection cover. The vertical mounting plate and the driving mechanism are arranged in the protective cover; and the test model at the top of the vertical mounting plate extends out of the protective cover shoulder cleft of the protective cover. The technical problem that in an existing hypersonic wind tunnel test, structural nonlinear factors such as gaps, friction and collision between kinematic pairs of an executing mechanism are ignored due to a simplified supporting mode, and consequently the influence of the performance of the executing mechanism in a complex vibration environment cannot be truly reflected by a test result is solved. And a reliable test means is provided for revealing a structural nonlinearity and pneumatic nonlinearity coupling effect rule.

This disclosure provides a control circuit for automatically switching operating modes, including a current generation circuit, a first current difference circuit, a second current difference circuit, a valley control circuit, a PFM detection circuit, and an oscillator. The current generation circuit converts the control voltage into a first control current and generates a second control current of the same magnitude as the first control current through a first mirror. The first current difference circuit generates a fixed bias current. When the first control current is greater than the fixed bias current, the control circuit operates in a fixed-frequency PWM mode. The second current difference circuit generates a third control current of the same magnitude as the first control current through the first mirror. The valley control circuit adjusts the valley current when the lower transistor is turned on, and controls the frequency of the switching node to decrease by reducing the valley current. When the third control current is less than the fixed bias current, the overcurrent signal of the lower transistor is high, and the control circuit reduces the frequency by decreasing the valley current.

Methods, apparatuses, and computer programs for supporting virtual machine performance measurements are disclosed. In one embodiment, a method includes: in response to a virtual machine entry to a virtual processing unit of a processor, writing a first count value and a second count value corresponding to the virtual processing unit to a first counter and a second counter, respectively; incrementing the first counter count at a fixed frequency based on the first count value, and incrementing the second counter count proportional to the architecture event occurrence of the virtual processing unit based on the second count value; and in response to exiting from the virtual machine of the virtual processing unit, reading the resulting first count value and the resulting second count value from the first counter and the second counter, respectively, to determine a measure of performance of the virtual processing unit.

The utility model relates to the technical field of antenna stealth, specifically relates to a frequency selection unit and frequency selection surface for low frequency range, the frequency selection unit is spliced by first metal layer, second metal layer, third metal layer and fourth metal layer, the first metal layer is formed by MXM square metal patch, wherein 3<=M<=7 and M is odd, second metal layer is spliced by four sub metal layer units and second metal layer is central symmetry structure, the sub metal layer unit is the structure after first metal layer equal proportion reduction to one fourth, third metal layer and first metal layer structure are same and both are in diagonal position, fourth metal layer and second metal layer structure are same and both are in diagonal position, the frequency selection unit structure simple in the utility model can realize the absorption of internal fixed frequency point electromagnetic wave, and the electromagnetic wave of other frequency is completely transparent, can satisfy the frequency selection of antenna, and does not influence the use of antenna itself.

The application provides a carbon nanotube composite charge generation layer, a preparation method thereof and application of the carbon nanotube composite charge generation layer in a laminated OLED device. The preparation method comprises the following steps: placing a ferrous oxide loaded carbon nanotube composite material in a solvent to obtain a solution, spraying the solution on a substrate surface, drying to obtain a modified base film; placing the modified base film in a magnetic field with a fixed direction and a fixed frequency to obtain a modified base film with oriented arrangement of carbon nanotubes; and preparing the carbon nanotube composite charge generation layer by using a high-vacuum evaporation method. Compared with the prior art, the carbon nanotube material with regular arrangement is obtained, the axial conductivity of the carbon nanotube material is far higher than the radial conductivity, the traditional evaporation process is used, the CGL is prepared on the carbon nanotube layer with regular arrangement by the thermal evaporation method, and therefore the electrical crosstalk (lateral conductivity) of the CGL is reduced, and the performance of the laminated OLED device is improved.

The invention provides a communication method and device, relates to the technical field of communication, and is used for solving the problem of link breakage between devices caused by inconsistent frequency hopping point tables of two communication parties. The method comprises the following steps: a first device sends a first signaling to a second device, wherein the first signaling is used for indicating to update a frequency hopping point table between the first device and the second device to a first frequency hopping point table; and under the condition that the updating of the first frequency hopping frequency point table fails, the first equipment communicates with the second equipment by using a fixed frequency point table agreed in advance. Thus, under the condition that the updating of the first frequency hopping frequency point table fails, the first device and the second device return to the fixed frequency point table agreed in advance, thereby ensuring that the first device and the second device use the same frequency point table for communication, avoiding the occurrence of link breakage between the devices, further reducing the system delay, enhancing the anti-interference capability, and improving the user experience. And the reliability and robustness of the system are improved.

The application discloses a stator lamination, a stator core, a motor, a compressor and a refrigeration device. The stator lamination comprises a yoke, a plurality of tooth portions and a plurality of recess structures. The plurality of tooth portions are arranged on the inner circumferential surface of the yoke and are arranged at intervals along the circumference of the yoke, and a stator slot is formed between two adjacent tooth portions. The plurality of recess structures are arranged at intervals along the outer circumferential surface of the yoke. The recess structure comprises a first recess and a second recess arranged at intervals. The first recess is arranged on the yoke corresponding to two adjacent tooth portions and the yoke corresponding to the stator slot between the two tooth portions. The second recess is arranged on the yoke corresponding to a tooth portion. The technical scheme can improve the stator fixed frequency and reduce the high-frequency carrier noise of the motor.

The application discloses a high-precision power frequency phase angle synchronous measurement method under an undefined frequency sampling condition, and the method comprises the following steps: cyclically recording a current sampling completion time t clk_k and a current sampling code value x k ; recording a pulse trigger time t clk_pulse when a synchronous pulse is triggered, and recording sampling values and sampling completion times of a certain number of cycles from the current time backward to form a sampling time-sampling code value record table; and performing fixed frequency correction on the sampling code values in the record table through high-order interpolation according to the current electrical quantity frequency. Since the application does not require very accurate sampling intervals and is not affected by context switching, interruption preemption and other problems, it is unnecessary to use a chip with higher performance of a bare core to process, chip cost is reduced, and therefore the application can be applied to low-voltage secondary devices which are more sensitive to cost.

This invention discloses a method for acquiring spread spectrum signals to eliminate the influence of high-speed data symbols, comprising the following steps: When down-converting the input signal obtained from the ADC sampling receiver, a fixed frequency offset is artificially introduced; a local pseudo-code sequence is correlated with the down-converted signal; the correlated signal is low-pass filtered; the I-path and Q-path of the filtered signal are multiplied, and the result is input to the FFT calculation module; the highest energy spectral line is found in the spectrum output by the FFT module, and the Doppler frequency offset of the input signal is calculated if the energy of this spectral line exceeds a threshold, then pseudo-code locking and carrier locking are performed; it is determined whether pseudo-code locking and carrier locking are completed: if locked, the acquisition process ends; if not locked, the phase of the local pseudo-code sequence is adjusted and the process returns to the down-conversion step. This invention can eliminate the influence of high-speed data symbol flipping on spread spectrum signal acquisition, is applicable to different data rates, and significantly enhances the communication capability of spread spectrum communication systems.

An energy-saving refrigeration type drying machine comprises a three-in-one heat exchanger, a pre-cooling cavity, a first heat exchange cavity, a second heat exchange cavity and a gas-water separation cavity are formed in the three-in-one heat exchanger, a gas inlet is formed in the upper end of the pre-cooling cavity, the lower end of the pre-cooling cavity is communicated with the first heat exchange cavity, and the lower end of the first heat exchange cavity is communicated with the second heat exchange cavity. The second heat exchange cavity communicates with the inlet end of the gas-water separation cavity, and the outlet end of the gas-water separation cavity penetrates through the pre-cooling cavity and communicates with the outlet channel. A first heat exchange pipe is arranged in the first heat exchange cavity, a second heat exchange pipe is arranged in the second heat exchange cavity, the first heat exchange pipe is connected with a first refrigerating system, and the second heat exchange pipe is connected with a second refrigerating system. According to the utility model, the defects in the prior art are overcome, and the required cooling capacity is controlled by adopting a variable-frequency and fixed-frequency dual-system series connection mode, so that the energy of the compressor can be used to the maximum extent, and the energy-saving effect of the system is achieved.

The invention discloses a time sequence data writing method, system and device and a medium, and is applied to the field of data storage, the method comprises the steps that sampling time sequence data of a plurality of continuous sampling time points for a detection object is acquired, and the sampling time sequence data comprises a sampling timestamp, a sampling measurement value vector and sampling meta information; determining the data type of each piece of sampling time sequence data, wherein the data type comprises abnormal data, anchor point data and normal fluctuation data; processing the corresponding sampling time sequence data based on the data type to obtain target time sequence data; and performing hierarchical storage on the multiple pieces of target time sequence data. The problem that in the prior art, all sampling points are recorded at a fixed frequency, and consequently a large amount of slowly-changed or invalid data are stored redundantly is solved.

A scattering parameter measurement device based on microwave photonic mixing includes a microwave generation module 1, a signal loading module 2, a local oscillator frequency generation module 3, a multi-channel microwave photonic mixing module 4, an analog-to-digital converter (ADC) module 5, and a signal processing module 6. Along the signal output direction of the multi-channel microwave photonic mixing module 4, the ADC module 5 and the signal processing module 6 are sequentially arranged. This invention utilizes microwave photonic mixing technology and a local oscillator source with relatively small bandwidth to down-convert a high-frequency microwave signal to a fixed-frequency intermediate frequency (IF) signal. This reduces the bandwidth requirements of the receiver's electronic components and the sampling rate requirements of the ADC. It abandons the traditional superheterodyne structure and / or direct conversion structure, using a miniaturized continuous optical module as the light source for microwave photonic mixing, simplifying the system structure and reducing cost and power consumption.