1666 results about "Phase-locked loop" patented technology

The invention discloses a sleep monitoring and intervention method and system based on electroencephalogram signals, and belongs to the technical field of sleep monitoring and intervention. The method comprises the steps that electroencephalogram signals are collected through a dry electrode worn on the head of a user; the signals are preprocessed; performing automatic sleep staging on the pre-processed signal based on a layered space-time joint modeling network, and outputting a waking period label, an N1 period label, an N2 period label, an N3 period label and an REM period label; whether intervention conditions are met or not is judged based on the staging labels and the real-time electroencephalogram spectrum features; and if yes, generating and applying an alternating current stimulation signal for intervention. The system comprises a wearable electroencephalogram acquisition device, a signal analysis module and an intervention module. According to the method, the deep learning model integrating front-end self-adaptive processing, the graph neural network and Transform is adopted for sleep staging, closed-loop phase synchronous stimulation driven by the digital phase-locked loop is combined on the basis, connection from sleep monitoring to closed-loop intervention is achieved, and the sleep monitoring accuracy and the intervention effect are effectively improved.

The invention discloses a stability analysis method for a hybrid grid-connected system of a grid-following converter, and the method comprises the steps: constructing precise impedance models of a grid-following type (GFL) converter and a grid-constructing type (GFM) converter respectively based on a phase-locked loop (PLL) mechanism and a virtual synchronous generator (VSG) control strategy, and the details are shown in an abstract figure 1; deducing the total equivalent impedance of the system at a point of common coupling (PCC) according to a circuit equivalence principle; performing stability analysis and sensitivity evaluation on different converter combination proportions, topological structures and key control parameters of the hybrid grid-connected system based on an impedance ratio criterion; and verifying the accuracy of the analysis result through frequency domain simulation. The method can be widely applied to a new energy power system, solves the problem of system stability evaluation and optimization under the high-proportion renewable energy access background, and has the characteristics of high adaptability, accurate model and comprehensive analysis.

The invention relates to the technical field of prediction algorithms, and discloses a high-precision active power filtering and prediction algorithm for a three-phase ammeter, which comprises the following steps: acquiring original signals of three-phase voltage and current for baseline correction, performing time-frequency analysis on non-stationary harmonic waves and noise of the original signals, and dynamically adjusting filtering parameters; voltage and current phase alignment is carried out through FIR phase shift and zero crossing point detection, a phase-locked loop is constructed by using GRU to track the frequency of a power grid, the sampling frequency is dynamically adjusted, and frequency mutation is detected; iapFFT transformation is optimized to suppress spectrum leakage, a phase error is corrected through a deep learning network, and weak harmonic detection is enhanced by using an attention mechanism; classifying harmonic waves, and adaptively calculating total active power; dimensionality reduction is carried out on historical power and environmental parameters through an auto-encoder, and future active power is predicted; low-power-consumption hardware is adapted, and training efficiency and data security are optimized; three-phase signals are processed in parallel, and FPGA storage and FFT / FIR cores are optimized for filtering processing; and dynamically adjusting parameters of the phase-locked loop.

The invention relates to the technical field of energy storage cooperative control, and discloses an improved energy storage converter grid following control algorithm, which comprises the following steps of: 1, extracting positive sequence and negative sequence components of three-phase voltage of a power grid through a double-sequence decoupling phase-locked loop, and acquiring a positive sequence axis component signal by adopting forward rotation coordinate transformation; and 2, when frequency locking is carried out based on the positive sequence axis component signal, extracting a voltage amplitude corresponding to the positive sequence axis component signal, and inputting the voltage amplitude to a feed-forward passivation module. An active power regulation technical scheme based on a frequency deviation threshold value is adopted, the technical effect of simulating the primary frequency modulation characteristic of a network-forming converter is achieved by detecting the power grid frequency deviation in real time and generating an active power compensation signal, and the defect that traditional network-following control lacks frequency active supporting capacity is overcome. And the converter can spontaneously increase the active power to stabilize the power grid frequency when the power grid frequency drops.

The invention relates to the technical field of power systems, in particular to a UPQC harmonic compensation method and system based on repetitive control, and the method comprises the steps: obtaining a load current signal and a voltage signal of a power distribution network, and extracting a harmonic instruction current based on the load current signal; and inputting the harmonic instruction current into a feed-forward channel constructed based on an adaptive filter, and generating a feed-forward control quantity. The phase and frequency of the voltage signal of the power distribution network are tracked in real time through a digital phase-locked loop, the fundamental frequency of the power grid is accurately solved, and the power distribution network can be accurately controlled. The internal model period and the phase lead compensation amount of the frequency adaptive repetitive controller are dynamically calculated, and the internal model structure of the repetitive controller is always matched with the current power grid frequency by updating the two core parameters in real time, so that the compensation precision decline caused by frequency deviation is avoided; and high-precision suppression of the periodic harmonic waves can be realized in a normal fluctuation range of the fundamental wave frequency of the power grid.

The invention provides a broadband tunable low-phase-noise photo-generated microwave signal source and device, and relates to the technical field of photo-generated microwaves. According to the invention, a low-frequency optical pulse and a high-frequency microwave signal are respectively input into the electro-optical sampling phase-locked loop; and the electro-optical sampling phase-locked loop determines the synchronization error of the optical pulse and the microwave signal based on the phase difference between the optical pulse center point and the microwave signal zero crossing point. And taking the synchronization error as a feedback signal, and continuously adjusting the frequency and the phase of the microwave signal by the voltage-controlled oscillation module until the frequency and the phase are synchronized with the Nth harmonic of the optical pulse. By setting different initial frequencies of the voltage-controlled oscillation module, microwave signals with different integral multiple optical pulse frequencies can be obtained, and broadband tuning of photo-generated microwave signals is realized. Furthermore, the repetition frequency of the frequency comb is locked through beat frequency of two beams of reference laser and two adjacent comb teeth, the stability of the reference laser is transmitted to the optical pulse, and the stability of the reference laser is further transmitted to the microwave signal through synchronization of the optical pulse and the microwave signal, so that the phase noise of the photo-generated microwave signal source is reduced.

The invention discloses a wind power converter oscillation characteristic suppression method, system and device based on broadband impedance scanning and a storage medium, and relates to the technical field of wind power grid-connected control, and the method comprises the steps: based on grid-connected steady-state small signal voltage disturbance injection, respectively extracting broadband response data of positive sequence impedance and negative sequence impedance, and constructing a machine end broadband impedance model; constructing an impedance phase and amplitude matching criterion based on the broadband impedance model in combination with the power grid side equivalent impedance, identifying risk frequency bands of subsynchronous and super-synchronous oscillation, and determining a dynamic influence interval related to the phase-locked loop bandwidth; adjusting a phase-locked loop bandwidth and a filtering parameter based on a risk frequency band and a dynamic influence interval, and executing d / q control link collaborative constraint in combination with a leakage matrix parameter; according to the method, accurate modeling of positive and negative sequence impedance of the wind power converter and bandwidth adaptive vibration suppression control are realized, and the stability and the anti-oscillation capability of the system are improved.

The invention discloses a hybrid effective flux linkage observer and a permanent magnet synchronous motor control method, device and system. The method comprises the following steps: carrying out Clarke conversion on an obtained three-phase current of the permanent magnet synchronous motor to obtain a current in a static coordinate system, and carrying out park conversion based on rotor position information to obtain a current in a synchronous rotating coordinate system; the effective flux linkage of the permanent magnet synchronous motor is obtained through the hybrid effective flux linkage observer; on the basis of the obtained effective flux linkage of the permanent magnet synchronous motor, dead-zone compensation voltage is obtained through self-adaptive gain dead-zone compensation calculation based on back electromotive force reconstruction, and the rotating speed and the rotor position of the permanent magnet synchronous motor are obtained through phase-locked loop calculation; according to the rotating speed and the rotor position of the permanent magnet synchronous motor, the current under the synchronous rotating coordinate system, the dead zone compensation voltage and the obtained reference rotating speed and reference current, the reference voltage of the motor at the k moment is obtained through a rotating speed loop and a current loop and used for achieving low-speed position-sensorless control over the permanent magnet synchronous motor.

The invention relates to the technical field of material detection, in particular to a silver coating adhesive force detection method based on multi-frequency impedance imaging, which comprises the following steps: applying a dual-mode multi-frequency excitation signal to the surface of a silver coating through an attached microelectrode array, synchronously acquiring voltage-current response data, and generating a dual-mode multi-frequency impedance original data set; performing time-varying impedance phase-locked separation on the dual-mode multi-frequency impedance original data set, extracting a dynamic impedance component of a coating-matrix interface region, and reconstructing a three-dimensional sub-interface impedance distribution diagram; and outputting an adhesive force quantized value through an oscillation frequency-adhesive force conversion model according to the spatial oscillation frequency characteristics of the impedance phase in the three-dimensional sub-interface impedance distribution diagram. According to the invention, a double-phase-locked loop system is adopted to realize the time-varying component demodulation of the impedance response of the silver coating-matrix interface, the low-frequency dynamic impedance signal modulated by silver ion migration is effectively extracted, and the weak change of the interface bonding state is sensitively reflected.

The invention discloses a mutual inductor digital output synchronism detection method and system, particularly relates to the field of electric power engineering detection, and is used for solving the problem of synchronism deviation concealment caused by phase-locked loop drift of digital output of an electronic mutual inductor in an intelligent substation. A uniform time frame is utilized to penetrate through the whole process, synchronization deviation is continuously mapped into a phase migration track, long-term drift and instantaneous jitter are analyzed on two scales by means of phase shift stacking quantity and pulse dispersion rate, two kinds of heterogeneous features are converted into a single drift tradeoff coefficient through Gaussian process regression, and a stability domain threshold value is dynamically revised according to the single drift tradeoff coefficient; after the threshold is triggered, the minimum adjustment amount is immediately issued to the phase-locked loop and is synchronously verified, so that the clock adjustment action and the drift monitoring are mutually nested; the protection device continuously receives the stable sampling sequence, the tripping misjudgment rate is remarkably converged, the inspection period is prolonged, and additional hardware investment is not needed.

The invention relates to the technical field of voltage sensitivity photovoltaic stability regulation and control of a power distribution network, in particular to a multi-parameter photovoltaic grid-connected voltage stability control method, system equipment and a medium, and aims to improve the transient modeling precision by constructing a second-order equivalent transient model of a photovoltaic system and decoupling a mapping relation between phase-locked loop parameters and equivalent inertia and damping; quantifying a transient stability boundary under voltage disturbance based on a phase-locked loop sensitive parameter, and determining a photovoltaic power angle critical safety threshold; for the whole voltage fluctuation process, dynamically and cooperatively regulating and controlling phase-locked loop parameters according to the voltage and frequency of the power grid; equivalent damping and inertia suppression oscillation are enhanced in the voltage drop period, inertia acceleration recovery is reduced while high damping is maintained in the voltage recovery period, rated parameters are reset in the steady state, the transient stability of the system for coping with voltage sag is remarkably improved, and the risk of power angle instability is avoided.

The invention relates to the technical field of communication, and discloses a network communication chip signal interference suppression processing method. The method comprises the following steps: acquiring a local oscillator phase jitter sequence in real time through an on-chip phase noise monitoring unit; estimating Doppler frequency shift and channel coherence time based on the sequence; dynamically adjusting the closed-loop bandwidth of the phase-locked loop; and generating a phase compensation signal, and performing time-varying channel minimum mean square error equalization in combination with a received baseband signal to eliminate inter-symbol interference. The system integrates a phase noise monitoring function module, a channel parameter estimation function module, a phase-locked loop bandwidth regulation function module, a phase compensation generation function module and an interference joint elimination function module. By means of dynamic bandwidth reconstruction and high-precision phase compensation, the bit error rate under high-speed movement is remarkably reduced, the 5G millimeter wave communication standard requirement is met, and the method has the advantages of being achieved on a whole chip, low in delay and high in robustness.

The invention provides a signal transceiving test system for simulating a shared local oscillator and a calibration method thereof, and the system comprises a signal generation module which outputs a baseband signal; the first local oscillator module comprises a first clock source, a first phase-locked loop and a first frequency multiplication channel, and the first frequency multiplication channel outputs a first local oscillator signal; the first frequency mixer is used for mixing the baseband signal and the first local oscillator signal to generate a modulation signal; the second local oscillator module comprises a second clock source, a second phase-locked loop and a second frequency multiplication channel, and the second frequency multiplication channel outputs a second local oscillator signal; the second frequency mixer is used for mixing the modulation signal and the second local oscillation signal to generate a demodulation signal; the signal analysis module is used for receiving and analyzing the demodulated signal; and the controller adjusts the first phase-locked loop or the second phase-locked loop. The problem that the phase difference of different local oscillators cannot be predicted can be solved while mutual interference of the shared local oscillators is avoided, so that the test calibration precision is improved.

The embodiment of the invention provides a delay measurement circuit and a memory. The delay measurement circuit is applied to the delay phase-locked loop and comprises a loop mark generation circuit which is electrically connected with a loop of the delay phase-locked loop and is configured to generate a loop mark signal and input the loop mark signal to the loop of the delay phase-locked loop when loop delay measurement is carried out on the delay phase-locked loop; after the loop mark signal circulates M times in the loop of the delay phase-locked loop, a measurement ending signal is generated, a target pulse signal is generated, and the effective pulse width of the target pulse signal is equal to M times of the loop delay; wherein M is an even number greater than 1; the counting circuit is electrically connected with the loop mark generation circuit and is configured to receive a frequency division clock signal, and the effective pulse width of the target pulse signal is timed by using the frequency division clock signal to obtain a timing result; and carrying out preset processing on the timing result to obtain a loop delay measurement result of the delay-locked loop. The embodiment of the invention is at least beneficial to increasing the margin value of the delay measurement circuit and improving the accuracy of loop delay measurement.

The invention discloses a data sampling timing error evaluation method based on an evaluation model, relates to the technical field of timing error evaluation, and solves the problem that timing error evaluation is not accurate enough. Wherein the sampling module realizes undistorted receiving and clock signal frequency output of a clock signal through a CMOS clock input circuit, a third-order digital phase-locked loop circuit and a DSP digital signal processing chip, and a Fourier phase difference algorithm removes harmonic interference to solve a phase difference between the clock signal and an ideal clock signal; the clock signal feature recognition unit adopts a convolutional neural network to carry out iterative training on a training set of the timing error evaluation module to obtain an error evaluation module, the error evaluation module and the time migration algorithm module realize accurate calculation of a timing error value, and the timing error value calculation accuracy is greatly improved.

The invention discloses a converter grid following-grid construction control mode smooth switching method suitable for wide-range source-grid state change. The method comprises the following steps: constructing a phase-locked loop control loop, a power outer loop control loop and a current inner loop control loop of a grid following type converter based on constant power control; constructing a voltage control loop, a phase control loop and a voltage and current double-closed-loop control loop of the network construction type converter based on the virtual synchronous generator VSG; calculating real-time output active power P and reactive power Q of the converter; constructing a voltage phase synchronization loop switching control loop and a current instruction tracking loop, and realizing smooth switching of dq-axis current instruction values output by a power outer loop of a following network type and a voltage outer loop of a construction network type; and the output dq-axis current instruction value is transmitted to a current inner loop to generate a final voltage signal, and a PWM wave is output to the converter through a modulation link. According to the method, a voltage phase synchronous switching compensation mechanism is adopted, a voltage amplitude and a phase signal are synchronously corrected in the mode switching process, and smooth change of an inner ring current reference signal is achieved.

The invention relates to the technical field of virtual impedance self-adaptive control of energy storage converters, in particular to a virtual impedance self-adaptive control method of a grid-forming type energy storage converter, which comprises the following steps of: acquiring three-phase voltage and current of a grid-connected point in real time; performing phase-locked loop processing and coordinate transformation to obtain a d-axis voltage, a q-axis voltage and a current under a synchronous rotating coordinate system; calculating instantaneous power, and obtaining active power and reactive power; virtual resistance and virtual inductance are calculated according to power fluctuation through an adaptive algorithm; the virtual impedance equation generates a voltage drop compensation signal; and superposing the compensation signal and the reference voltage to generate a new modulation wave, and inputting the new modulation wave into the pulse width modulation module to realize power oscillation suppression and stable operation. According to the method, the problems between damping enhancement and loss reduction in network construction type control are solved, the dynamic and steady-state performance of the converter is improved, and a key technical support is provided for large-scale and high-reliability application of the network construction type energy storage converter in a novel power system.

The invention relates to the technical field of new energy grid-connected control, in particular to a fault stage transient stability analysis method and system for a following-constructed network type converter series-parallel system, and the method comprises the steps: enabling a constructed network type converter to be equivalent to a controlled voltage source series impedance, enabling a following network type converter to be equivalent to a controlled current source, and enabling the controlled current source to be equivalent to a controlled voltage source series impedance; the whole series-parallel system is equivalent to a scene in which double voltage sources and a single current source are jointly connected in parallel to a PCC point, and a series-parallel system model is constructed; according to the series-parallel system model, respectively representing an active power coupling term of the network-building type converter and a voltage coupling term of the network-following type converter under the condition of considering parallel connection of the network-following type converter and the network-building type converter; according to the coupling term, remodeling an active loop control structure of the network-constructing converter and a phase-locked loop synchronization structure of the network-following converter, and obtaining a transient analysis model of the series-parallel system considering the coupling term; the transient stability of the hybrid system in the power grid fault stage is analyzed through the transient analysis model, and the influence on the transient stability is effectively represented.

The invention discloses a permanent magnet synchronous motor sensorless control method based on a dynamic position error. A transition stage is provided, per-unit estimation position errors between a first position error signal obtained based on a high-frequency signal injection method and a second position error signal obtained based on a sliding mode observer are compared, an optimal switching speed point is dynamically determined, smooth fusion is carried out on the two position errors by using a nonlinear weighting function, and the optimal switching speed point is obtained. And finally, the estimated position and rotating speed are obtained through a phase-locked loop. And finally, position tracking is carried out by adopting different error signals according to the estimated rotating speed. According to the method, the problem of estimation value pulsation and jump caused by the fact that a traditional method depends on fixed experience switching points is solved, smooth and self-adaptive switching of the two estimation methods in the full-speed domain range is achieved, the control precision and operation stability of the system are remarkably improved, the structure is simple, and engineering implementation is easy.

An apparatus includes a phase-locked loop (PLL) circuit and a logic circuit. The logic circuit may manage, via one or more programmable operating parameters of the PLL circuit, PLL bandwidth variation exhibited by the PLL circuit due to variations in its manufacturing process (P), supply voltage (V) or temperature (T), i.e., PVT variations exhibited by the PLL circuit.

The invention relates to a motor encoder protocol real-time conversion device and a minimum delay method, and the method is characterized in that a high-precision clock is arranged in a protocol converter, and the following steps are executed: periodically reading position data from an encoder, recording a latching moment and a position value of the encoder, and calculating a real-time speed; and when a position reading request of the driver is received, recording a request moment, carrying out interpolation calculation by utilizing a set calculation formula, and returning a compensated real-time position to the driver. In order to minimize time delay, a phase-locked loop is adopted, the request time of the driver is taken as a reference, and the reading trigger time sequence of the encoder is synchronized and subjected to phase adjustment, so that the encoder can respond to the next request of the driver as soon as possible after data reading is completed, and the interpolation error is reduced to the minimum. The method effectively solves the problem of position transmission delay when encoders and drivers of different protocols are interconnected, and is suitable for high-precision servo control.

According to an embodiment, a phased-locked loop (PLL) circuit, within a gyroscope system, generates demodulation signals. It includes a phase frequency detector receiving gyroscope output, which compares a reference signal with a feedback signal to produce an error signal. A charge pump then converts this error into a first analog control signal. A programmable clamp circuit refines this into a second analog control signal. A voltage-controlled oscillator uses the second signal to produce an output signal at a controlled frequency determined by the clamp circuit. A frequency divider sends a comparison frequency signal back to the detector, completing the loop.

The invention discloses an Internet of Things flowmeter data compression sensing transmission optimization method and system, particularly relates to the field of low-power-consumption wireless communication networks, and is used for solving the problem of compressed sensing signal distortion caused by sampling time sequence misalignment in an LPWAN bandwidth limited environment. Constructing a local phase reference by extracting a pipeline vibration fundamental frequency component, and receiving a cloud synchronization reference timestamp alignment signal; fundamental frequency and third harmonic components are separated to calculate arrival time difference, and a phase-locked loop is triggered to dynamically adjust the phase of a sampling clock based on a pipeline material threshold value; after the stability of the zero crossing point time variance is verified, compressed sensing sampling is performed on the flow signal by adopting a phase synchronous clock, and an optimized compressed measurement value is generated and transmitted to the cloud through the LPWAN; through closed-loop cooperation of physical characteristics and a communication clock, complete capture of a signal sparse structure is guaranteed under a low-bandwidth condition, and cloud reconstruction precision is significantly improved.

The invention belongs to the technical field of clock chips, and discloses an intelligent calibration multi-channel clock chip system and a control method, the system comprises a coprocessor, an initial phase-locked loop, a selector and a plurality of clock output branches; the clock output branch comprises a numerical control circuit and a frequency divider which are connected with each other; the initial phase-locked loop is used for receiving an input clock signal, performing frequency multiplication on the input clock signal to obtain a reference clock signal, and sending the reference clock signal to the numerical control circuit of the at least one clock output branch through the selector; and the numerical control circuit is used for eliminating the distributed transmission delay difference in the reference clock signal by adopting a digital compensation algorithm, generating a target clock signal according to the reference clock signal after the delay difference is eliminated, and sending the target clock signal to the corresponding frequency divider. According to the invention, the absolute synchronization error of each clock output branch can be reduced, and the application scene diversity and flexibility of the clock chip are improved.

The invention provides a grid-connected converter fault transient process control parameter security domain determination method and device, and relates to the technical field of power systems. The grid-connected converter fault transient process control parameter safety domain determination method comprises the following steps: solving a power system equation of a target phase-locked loop by using structural parameters of a target power grid, and obtaining a first analytical expression of an output phase of the target phase-locked loop in a low-voltage ride-through stage after a short-circuit fault occurs in the target power grid; according to the first analytical expression, determining a low-pass phase-locked stability constraint; wherein the low-voltage ride-through phase-locked stable constraint is used for constraining that the output phase of the target phase-locked loop is not out of step in the low-voltage ride-through stage; determining a first parameter domain of a control parameter of the target grid-connected converter according to the low-pass phase-locked stability constraint; and determining a control parameter security domain of the target grid-connected converter based on the first parameter domain. According to the method, the safety domain of the control parameters of the grid-connected converter can be efficiently and accurately determined, so that the short-circuit fault ride-through capability of the grid-connected converter is effectively improved.

The invention provides a control method and system of a permanent magnet synchronous motor, computer equipment and a medium, and belongs to the field of motor control, and the method comprises the steps: obtaining stator current and voltage signals of the permanent magnet synchronous motor; constructing and operating a second-order sliding mode observer to output a stator current observation value; based on the current observation error and the change rate thereof, constructing a mixed sliding mode surface containing a linear term and a nonsingular terminal term, and designing a sliding mode control law; the control law is fed back to an observer to correct the observation process, and meanwhile two-phase observation counter electromotive force which is free of buffeting and does not need low-pass filtering is directly exported; closed-loop demodulation is carried out on the back electromotive force through a phase-locked loop, estimated values of the rotor position and the rotating speed are extracted, and finally position-sensorless vector control of the permanent magnet synchronous motor is achieved. According to the method, the buffeting phenomenon of a traditional sliding-mode observer is inhibited, a low-pass filter is avoided, phase lag is eliminated, and the estimation precision and the dynamic response performance of the system are improved.

The invention belongs to the related technical field of motor control, and discloses a phase angle estimation method, a phase-locked loop and a control system of a permanent magnet synchronous motor, and the phase angle estimation method comprises the steps: taking a d-axis component or a q-axis component of an observed back electromotive force vector as an evaluation function, taking an extreme value obtained by the evaluation function as an optimization target, and obtaining a phase-locked loop at (0, 0, 0); the phase angle of the permanent magnet synchronous motor is estimated according to the theta opt; when the optimization target is that the d-axis component is maximum, the formula is equal to theta opt-pi / 2; when the optimization target is that the d-axis component is minimum, = theta opt-3pi / 2; when the optimization target is that the q-axis component is maximum, = theta opt; and when the optimization target is that the q-axis component is minimum, = theta opt-pi. According to the method, the estimation of the phase angle can be quickly realized through a simpler method, so that the dynamic speed response capability of a system controlled by the permanent magnet synchronous motor is remarkably improved.

A radar system injects a calibrated current at a signal generator during a reset portion and acquisition portion of each chirp period. The signal generator employs “gear-switching” to reduce PLL bandwidth during an acquisition phase and to increase the phase lock loop (PLL) bandwidth during a reset phase. By employing gear switching to change the bandwidth of the PLL circuit during the different portions of each chirp period, the length of the reset period is reduced, thus improving overall efficiency of the radar system while maintaining good performance.