Phased array radar antenna transmitting and receiving protection time test method and system

Abstract

The application discloses a phased array radar antenna transmitting-receiving protection time testing method and system, relates to the mineral product screening technical field, and comprises the following steps: S100, a mute time window is inserted along a time axis extended from a tail part of a transmitting pulse, a mute area for accommodating a residual wave of the transmitting signal is formed, a time curve of a signal attenuation process is constructed, and a residual energy path scale line is drawn based on the time curve; S200, a frequency-by-frequency scanning is performed in a main frequency bandwidth range based on the residual energy scale line, a backfolding gathering area of residual energy in a frequency spectrum space is extracted, a relationship between a corresponding frequency point and a time point is recorded, and a backfolding point list containing an energy backfolding position is formed. The application combines power pre-declining, frequency rotation and reverse frequency scanning, removes folding energy point by point in a ring spectrum channel, guides a tail wave into a time gap band, prevents interference to a receiving channel, improves transmitting-receiving switching stability, reduces a misjudgment protection triggering probability, and realizes active regulation and control of tail wave interference.

Description

Technical Field

[0001] This invention relates to the field of mineral screening technology, specifically to a method and system for testing the transmit and receive protection time of a phased array radar antenna. Background Technology

[0002] Phased array radar antenna transmit / receive protection time testing refers to the process of accurately measuring and verifying the safety interval time set during transmit / receive switching to prevent damage to key components such as power amplifier units and receiver front-ends due to signal overlap or delayed switching, under the antenna's time-division multiplexing operation mode. This test constructs a pulse timing control mechanism and utilizes high-precision timing generators, high-speed oscilloscopes, and beam controllers to calibrate the time delay between transmit shutdown and receive activation at the nanosecond level, measuring the minimum protection time threshold, dynamic switching delay, and consistency deviation between multiple channels. The test also incorporates extreme temperature and stress environment simulations and integrates fault prediction and health management concepts to evaluate the stability of the protection time, health status trends, and potential failure risks under different operating conditions. Through this test, the optimal protection window for the antenna during transmit / receive switching can be accurately determined, avoiding signal crosstalk and component overload damage in the transmit / receive paths, further improving the system's fault prediction and health management capabilities, and ensuring the detection accuracy and long-term stable operation of the phased array radar system.

[0003] The existing technology has the following shortcomings:

[0004] In existing technologies, phased array radar antennas, operating in time-division multiplexing mode, typically rely on frequency synthesizers and pulse timing control circuits to achieve the timing connection between transmit shutdown and receive startup. However, during multiple high-speed handover tests, the transmitted spectrum often fails to completely attenuate within the limited protection time, resulting in residual frequency components superimposing and folding back in the spectral space, forming a spectral folding phenomenon. This phenomenon leads to abnormal aliasing signals within the main frequency band, causing the system's frequency determination module to misjudge during delay verification. The module mistakenly interprets the instantaneous phase drift caused by frequency superposition as an excessive transmit / receive handover delay, thus triggering abnormal protection actions, leading to test interruption or false triggering of the protection module.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a method and system for testing the transmit and receive protection time of a phased array radar antenna, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for testing the transmit / receive protection time of a phased array radar antenna, comprising the following steps:

[0008] S100, a silent time window is inserted along the extended time axis of the transmitted pulse to form a silent zone for accommodating the aftershock of the transmitted signal, a time curve of the signal attenuation process is constructed, and the aftershock scale line of the residual energy path is drawn based on the time curve.

[0009] S200 performs frequency-by-frequency scanning within the main frequency bandwidth based on the reverberation scale line, extracts the reversal and accumulation regions of residual energy in the spectral space, and records the relationship between the corresponding frequency points and time points to form a list of reversal points containing the energy reversal positions.

[0010] S300, based on the frequency and time data recorded in the turnaround point list, constructs a time slot band on the time axis to delay the reception operation, delaying the reception start action until the time interval after all residual energy has decayed, forming an avoidance time structure for transmission and reception switching;

[0011] S400 adjusts the transmit pulse envelope curve according to the avoidance time structure and performs tail power pre-drop processing before the transmit signal is turned off, so that the tail signal energy is introduced into the constructed time slot band and a diversion sequence for energy guiding attenuation is generated.

[0012] The S500 utilizes a diversion sequence to drive a spectrum gating mechanism to perform frequency rotation switching around the main frequency bandwidth. Simultaneously, a reverse frequency sweep operation is applied during the spectrum rotation process, causing residual folded energy to be released in segments within the constructed ring spectrum channel, thereby achieving dynamic regulation and dissipation of spectrum folded energy.

[0013] Preferably, step S100 includes:

[0014] Extend the time axis along the tail of the transmitted pulse signal, and insert a silent time window at the beginning of the extension to keep the receiving front end in the silent zone and capture the natural decay waveform of the transmitted tail wave.

[0015] Within the silent time window, a high-sensitivity probe is used to sample and record the trajectory of signal amplitude change with high time resolution, and the attenuation waveform curve of the wake signal is plotted.

[0016] The energy decay rate is calculated in segments based on the decay waveform. Time points below the peak percentage threshold are extracted and marked to form decay characteristic scale lines.

[0017] Based on the key time points of the attenuation characteristic scale line and combined with the spatial propagation and reflection characteristics, the residual energy propagation path trajectory is constructed, and a spatiotemporal mapping map of the energy path is formed by monitoring nodes from multiple angles.

[0018] Preferably, the duration of the silent time window is set to be less than the time interval of the pulse period, and the rise time of the high-sensitivity probe is less than the attenuation characteristic time of the transmitted signal. By deploying multiple electromagnetic wave reflection monitoring nodes in the transmission path, multi-angle synchronous observation of the wake energy is achieved to ensure the accuracy of the correspondence between the aftershock scale line and the spatial path.

[0019] Preferably, step S200 includes:

[0020] Based on the constructed aftershock scale, the main frequency bandwidth range is selected as the scanning target. The frequency band is divided into equally spaced scanning frequency points, and low-power probe waves are emitted at each frequency point to detect sudden changes in energy rise.

[0021] The detected frequency points are classified according to the correspondence between energy intensity and time, a binary data structure of frequency and time is established, and the energy density index is calculated.

[0022] The energy data at all frequency points are sorted and filtered to remove isolated noise interference signals and select energy clusters with concentrated intensity and continuous frequency distribution.

[0023] A list of turnaround points is generated based on the frequency and time boundary information of the energy accumulation zone, recording the frequency range, energy threshold level, decay time period and aftereffect scale line mapping range, which is used for subsequent avoidance time structure construction.

[0024] Preferably, step S300 includes:

[0025] The frequency ranges and energy accumulation periods recorded in the turnaround point list are extracted as the starting point for the reception action delay window, and a safety buffer time is added after the accumulation period to determine the safe reception start point.

[0026] The delay windows corresponding to each frequency band are uniformly mapped on the time axis, delay time slices are established and overlapping intervals are merged to form a continuous time slot band.

[0027] The receiving control logic is adjusted according to the time slot band formed, and the receiving start action is delayed until the end of the slot band and the receiving window is extended thereafter to ensure data integrity.

[0028] During continuous pulses, the time slot band is finely adjusted cycle by cycle based on real-time energy accumulation data to maintain dynamic consistency between the avoidance time structure and the wake behavior.

[0029] Preferably, when adjusting the receive start-up action, the delay control signal and the transmit shutdown signal are synchronously calibrated, and the receive start-up time error is limited to a preset time range by a high-precision timing control unit. The receive channel is kept closed within the time slot to prevent tailwave energy interference, thereby achieving stable triggering of the receive action after the energy has completely decayed.

[0030] Preferably, step S400 includes:

[0031] Based on the constructed avoidance time structure, the transition time for guiding energy decay is determined, and a continuously decreasing power pre-adjustment segment is introduced at the end of the transmit pulse envelope to allow the energy to smoothly transition to the beginning of the time slot.

[0032] The pre-falling portion of the transmit envelope curve is designed by combining the power amplifier's response capability and signal modulation characteristics, and the power is controlled to gradually decrease from the peak value to the minimum value to avoid reflection interference;

[0033] During the pre-descent process, a frequency-selective attenuation channel is established, and the wake wave energy is guided into the time slot band through a directional coupler to complete the energy absorption.

[0034] After the diversion operation is completed, the diversion sequence and tailwave data are compared to verify the coupling consistency between the power drop curve and the avoidance time structure and to confirm the spectral purity.

[0035] Preferably, during the power pre-decline process, the energy guidance channel composed of an adjustable attenuator and a directional coupler is used to achieve directional absorption of the wake wave energy. The output of the attenuator is connected to an electromagnetic dissipation device to absorb low-intensity signals during the power decline phase and prevent energy reflection to the transmission path, ensuring that the wake wave energy is completely attenuated within the time slot and maintaining spectral stability.

[0036] Preferably, step S500 includes:

[0037] A rotating spectral window is constructed based on the power attenuation trajectory and time distribution pattern in the diversion sequence, and periodically offset on both sides of the main frequency bandwidth to form a frequency switching path;

[0038] By superimposing a reverse frequency sweep operation in the rotating spectrum window, a frequency sweep structure that gradually shrinks from the outside to the inside is formed in order to guide the wake energy to be released towards the main frequency.

[0039] After completing frequency rotation and reverse frequency sweep, a ring spectrum channel is constructed to connect the frequency switching path and the frequency sweep trajectory into a closed energy dissipation band, thereby achieving segmented energy release.

[0040] After the spectral energy release is completed, the time-frequency composite verification mechanism confirms that the energy in the spectral loop passband is cleared and restored to the initial state of the next transmission cycle.

[0041] The phased array radar antenna transmit / receive protection time test system includes a reverberation measurement module, an energy focusing analysis module, a receive avoidance control module, a transmit energy guidance module, and a spectrum dynamic adjustment module.

[0042] The aftereffect measurement module inserts a silent time window along the extended time axis of the transmitted pulse to form a silent zone for accommodating the aftereffect of the transmitted signal, constructs a time curve of the signal attenuation process, and plots the aftereffect scale line of the residual energy path based on the time curve.

[0043] The energy focusing analysis module performs a frequency-by-frequency scan within the main frequency bandwidth based on the aftereffect scale line, extracts the reversal and accumulation regions of residual energy in the spectral space, and records the relationship between the corresponding frequency points and time points, forming a list of reversal points containing the energy reversal locations;

[0044] The receive avoidance control module constructs a time slot band on the time axis to delay the reception operation based on the frequency and time data recorded in the turnaround point list. This delays the reception start action until the time interval after all the residual energy has decayed, forming an avoidance time structure for transmit / receive switching.

[0045] The transmission energy guidance module adjusts the transmission pulse envelope curve according to the avoidance time structure and performs tail power pre-decline processing before the transmission signal is turned off, so that the tail signal energy is introduced into the constructed time slot band and a diversion sequence for energy guidance attenuation is generated.

[0046] The spectrum dynamic control module uses a diversion sequence to drive a spectrum gating mechanism to perform frequency rotation switching around the main frequency bandwidth. At the same time, a reverse frequency sweep operation is applied during the spectrum rotation process, so that the residual folded energy is released in segments in the constructed ring spectrum channel, thereby realizing the dynamic control and dissipation of spectrum folded energy.

[0047] The technical effects and advantages provided by the present invention in the above technical solution are as follows:

[0048] This invention introduces a power pre-decay process in the transmit tail segment to actively guide residual energy into a pre-constructed time slot band. Combined with frequency rotation and reverse frequency sweep mechanisms, it achieves point-by-point removal of folded energy within the ring spectrum channel, effectively preventing residual frequency components from superimposing interference in the main frequency band. This prevents the receiving channel from being falsely triggered before reaching the energy safety threshold. Furthermore, the diversion sequence constructed in this scheme is coupled with the dynamic spectrum control process, giving the energy release path both temporal adaptability and frequency domain discreteness. This ensures the stability of the transmit / receive switching window and significantly reduces the probability of triggering false alarm protection actions, achieving proactive prevention and control of tailwave interference and a comprehensive improvement in system operational stability. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0050] Figure 1 This is a flowchart of the phased array radar antenna transmit / receive protection time test method of the present invention.

[0051] Figure 2 This is a schematic diagram of the phased array radar antenna transmit / receive protection time test system of the present invention. Detailed Implementation

[0052] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0053] This invention provides, for example Figure 1 The phased array radar antenna transmit / receive protection time test method shown includes the following steps:

[0054] S100, a silent time window is inserted along the extended time axis of the transmitted pulse to form a silent zone for accommodating the aftershock of the transmitted signal, a time curve of the signal attenuation process is constructed, and the aftershock scale line of the residual energy path is drawn based on the time curve.

[0055] To address the issue of residual transmit wake waves during the transmit-receive switching process of phased array radar antennas, a method is proposed to accurately capture and characterize the attenuation path of the wake waves by inserting a silent time window. This method is used to construct the foundational information for subsequent spectrum folding identification and processing. The specific implementation steps are as follows:

[0056] The time axis is extended along the tail of the transmitted pulse signal, and a silent time window is inserted at the beginning of the extension. This silent window should be much shorter than the entire pulse period, typically between 50 and 200 nanoseconds, to completely shield the receiving channel from activation, thus preventing crosstalk from residual transmitted signals on the receiving path. The silent time window is inserted as follows: after the original transmit shutdown point T0, the delay controller sets a high-impedance time interval, keeping the receiving front-end off within this interval while the signal detection link continues to operate to capture the natural attenuation waveform of the transmit tail wave under no-load conditions. This silent time window does not carry communication or detection tasks; it serves only as a temporary buffer for observing the energy of the signal tail. For example, for a medium-range radar with a typical operating frequency of 9.2 GHz, a pulse width of 1 microsecond, and a pulse repetition frequency of 1 kHz, a silent time window of 100 nanoseconds can be set, and the signal should immediately enter this window after the transmit shutdown.

[0057] Within the silent time window, a high-sensitivity probe is used to sample the signal along the transmission path in real time. A high-speed data acquisition device records the signal amplitude variation trajectory with a time resolution of less than 1 nanosecond, thus obtaining the complete attenuation process of the tailwave signal. The key to the sampling process is ensuring that the probe does not introduce additional impedance and has sufficient bandwidth coverage. A time-domain voltage probe with a rise time of less than 0.5 nanoseconds and a frequency response covering the range of 0.5 GHz to 12 GHz is recommended. The recorded signal attenuation data is plotted as a waveform curve with time on the horizontal axis and amplitude on the vertical axis. The falling edge of the tailwave will form a clear descent trend line. This trend line is used to observe whether there is hysteresis in the residual energy across multiple pulse cycles, i.e., whether the energy not completely dissipated in the previous cycle superimposed on the energy in the subsequent cycle.

[0058] Based on the acquired wake attenuation waveform, the energy attenuation rate at each point along the signal path is further calculated segmentally. The moments when the energy falls below a certain threshold are extracted and marked on the time axis, forming attenuation characteristic scale lines for subsequent judgment. Using the signal peak amplitude as a reference threshold, for example, 10%, 1%, and 0.1% of the peak value correspond to three calibration points T1, T2, and T3, respectively, to reflect different degrees of energy attenuation. For example, in a typical dataset with a peak value of 5.2V, a 0.1% threshold is set to 5.2mV, corresponding to a time calibration point of 78.5 nanoseconds after transmit shutdown. All calibration points are covered on the time axis as scale lines, forming a continuous attenuation scale interval, and the estimated residual power density of the signal is recorded at each point. This scale line not only reflects the energy attenuation rate but also reveals the time interval during which residual energy may fold back or reflect in the frequency domain, providing a time reference benchmark for spectrum folding detection.

[0059] Based on the key time points determined by the attenuation scale, and combining the reflection characteristics of the transmitted signal in its spatial propagation path with the echo response characteristics of the equipment, a complete residual energy propagation path trajectory is constructed. This trajectory is achieved by deploying multiple electromagnetic wave reflection monitoring nodes in the test environment to jointly observe the behavior of the transmitted wake wave from multiple angles, including spatial reflection, path coupling, and structural echo. These observation points are synchronized with the attenuation scale on the time axis, forming a spatiotemporal mapping of the energy path. For example, if a monitoring point is set at a 30-degree distance from the antenna main lobe, and a reflected signal wave with an intensity of 1.8 mV is received within 90 nanoseconds after transmission shutdown, coinciding with the attenuation scale of the main path at the same time point, then this point can be confirmed as a possible energy reversal source. The resulting aftershock scale not only includes time scale information but also incorporates spatial propagation characteristics, establishing a connection between wake wave attenuation and the possibility of frequency domain energy reversal, providing a precise and usable reference benchmark for subsequent spectrum scanning and reversal point extraction.

[0060] S200 performs frequency-by-frequency scanning within the main frequency bandwidth based on the reverberation scale line, extracts the reversal and accumulation regions of residual energy in the spectral space, and records the relationship between the corresponding frequency points and time points to form a list of reversal points containing the energy reversal positions.

[0061] To identify regions in the spectral space where the transmitted wake may experience energy reflection, a frequency-by-frequency scan of the main frequency bandwidth is performed based on the acquired aftershock scale, and the energy accumulation is recorded to form a list of reflection points with a frequency-time correspondence. The specific implementation steps are as follows:

[0062] Based on the constructed aftershock scale, the main frequency bandwidth range of the test signal is selected as the scanning target. This frequency range is typically determined by the transmission system; for example, with a center frequency of 9.2 GHz and a bandwidth of 200 MHz, the scanning interval is set to 9.1 GHz to 9.3 GHz. This frequency range is divided into equally spaced scanning frequencies, with a recommended frequency interval of no more than 200 kHz to achieve higher spectral resolution. Within this band, low-power probe waves are transmitted into the spectral space at each frequency point. Simultaneously, within the time interval corresponding to the aftershock scale, a high dynamic range receiving channel monitors each frequency point for any corresponding energy rise abrupt changes on the time axis, paying particular attention to sudden echo signals appearing between 50 and 150 nanoseconds after transmission. These signals may originate from frequency domain foldbacks or structural couplings of the wake. If the energy peak corresponding to a certain frequency point reaches more than five times the background noise within the silence window and lasts for more than 10 nanoseconds, then that frequency point is marked as a candidate foldback point.

[0063] The detected candidate frequencies are categorized according to their energy intensity and corresponding time of occurrence, establishing a frequency-time binary data structure. The corresponding energy density index is then calculated for each group of data. Specifically, the amplitude value is integrated within the time period of the acquired signal to estimate the energy level, and weights are assigned based on the degree of overlap between the occurrence time and the aftershock scale. For example, a frequency at 9.185 GHz experiences a sudden energy change 85 nanoseconds after transmission shutdown, with a peak amplitude of 3.2 millivolts, corresponding to an integrated energy of approximately 0.82 microjoules. This time point falls within 5 nanoseconds before and after the 0.1% attenuation threshold marked on the aftershock scale, suggesting that this frequency is highly likely related to the residual energy of the wake wave. All such frequencies are recorded with detailed parameters including their precise frequency value, corresponding occurrence time, peak voltage, integrated energy value, and degree of overlap with the aftershock scale.

[0064] After completing the frequency energy concentration analysis, all frequency points are sorted from high to low energy intensity, and isolated noise interference signals, i.e., those frequencies that appear only for a very short time and do not have a time correspondence with any attenuation threshold, are further eliminated. After data screening, regions with concentrated intensity and continuous frequency distribution are selected to form energy concentration zones in the spectral space. For example, if there are 6 consecutive frequency points marked as high-energy candidate points between 9.172 GHz and 9.190 GHz, and the corresponding time points are concentrated between 80 nanoseconds and 95 nanoseconds after transmission, then this frequency band is defined as the first energy concentration zone. The time windows of these concentration zones are further confirmed, and the start and end frequencies, peak energy time, duration, and overlap measurement parameters of each concentration band are recorded.

[0065] Based on the frequency and time boundary information of the energy accumulation area, a complete list of turnaround points is generated to guide the subsequent construction of the avoidance time structure. The turnaround point list records the frequency range, energy threshold level, corresponding attenuation time period, and mapping range to the aftershock scale for each group of spectrum accumulation areas in list form. For example, one item in the list records the following: frequency band range of 9.172 GHz to 9.190 GHz, maximum energy peak of 1.6 microjoules, accumulation time range of 82.5 nanoseconds to 96.2 nanoseconds, and corresponding aftershock scale coverage of 92%. This list not only has frequency positioning capabilities but also serves as a tool for marking dangerous energy windows on the time axis. After the list is generated, all identified turnaround point frequency bands will be used in subsequent steps to dynamically adjust the receiving action timing and the power envelope curve of the transmitted signal tail segment, thereby establishing an active prevention and control structure against residual energy interference.

[0066] S300, based on the frequency and time data recorded in the turnaround point list, constructs a time slot band on the time axis to delay the reception operation, delaying the reception start action until the time interval after all residual energy has decayed, forming an avoidance time structure for transmission and reception switching;

[0067] To prevent wake wave energy from affecting the normal startup of the receiving channel within the spectral foldback region, a time slot band for delayed reception needs to be constructed based on the aforementioned list of foldback points. This establishes a transmit / receive switching time structure that avoids residual energy. The specific implementation steps are as follows:

[0068] Extract the identified frequency bands and their corresponding energy accumulation periods from the list of return points to determine the starting point for the reception delay window. Taking a typical return point as an example, assuming its frequency is concentrated between 9.172 GHz and 9.190 GHz, the corresponding energy accumulation time extends from 82.5 nanoseconds to 96.2 nanoseconds. For this accumulation period, an additional safety buffer time is added to its right to ensure that the residual field strength after the signal tail has completely attenuated no longer affects reception initiation. This safety buffer time is determined based on the system's noise margin and receiver sensitivity, and is generally set between 10 and 30 nanoseconds. For example, if the system no longer responds to tailwave power less than 0.05 microwatts, and the signal still shows a tail signal attenuation trend of 3.7 millivolts after 96.2 nanoseconds, then the delay can be extended by 20 nanoseconds, determining the final safe reception starting point as 116.2 nanoseconds.

[0069] All frequency bands' corresponding delay windows are mapped onto a unified time axis to establish multiple independent delay time slices. The overlap of these time slices within a single pulse period is analyzed. If the energy accumulation times of multiple frequency bands highly overlap, they are merged into a continuous slot band structure; if they appear scattered, their respective start and end points are marked on the time axis. Taking a specific pulse period as an example, if three sets of reversal points are identified, located in the intervals of 82.5 to 116.2 nanoseconds, 90.0 to 125.0 nanoseconds, and 105.0 to 140.0 nanoseconds respectively, then there is overlap between them. After merging, a unified slot band is formed, spanning 82.5 nanoseconds to 140.0 nanoseconds. The length of this slot band is the minimum time structure that must be avoided during receiver startup, used to comprehensively avoid interference from residual energy on the receiving path.

[0070] Based on the established slot band structure, the timing triggering logic of the receiver controller is reconfigured. The original planned receiver activation time, which was initially set to start immediately after the transmit signal was turned off, is now delayed until after the slot band ends. For example, in normal operation, the receiver is set to activate 50 nanoseconds after transmit shutdown. However, the slot band end time, constructed based on the current turnaround point list, is 140 nanoseconds. Therefore, the clock control logic of the receiver channel needs to be adjusted to move the activation signal trigger point to 140 nanoseconds after shutdown. This operation must maintain a time accuracy better than 5 nanoseconds to ensure the receiver activates at the accurate time and avoids entering the residual energy region. Simultaneously, to ensure that the system's receiving performance does not degrade, an appropriately extended receiving window needs to be added after the slot band to compensate for the reduced effective detection time due to the delay. For example, if the original planned receiving window was 900 nanoseconds, it is extended to 920 nanoseconds due to a 20-nanosecond delay to ensure the integrity of the received data.

[0071] To ensure the dynamic adaptability of the slot band, a feedback adjustment strategy is introduced during continuous pulse repetition. Based on the real-time energy accumulation data collected during each pulse test, the slot band is fine-tuned cycle by cycle. Specifically, after each pulse cycle, the actual wake wave data collected in that cycle is compared with historical turnaround point data. If a change is found in the energy peak value or duration at a certain frequency point within the current cycle, the corresponding slot band start and end points are recalculated. For example, if the energy accumulation time in the 9.180 GHz band is found to have increased from 96.2 nanoseconds to 102.5 nanoseconds in the 5th cycle, the original slot band end should be delayed by 6.3 nanoseconds to form a new time structure. Through this cycle-by-cycle dynamic adjustment method, the avoidance time structure can closely match the actual wake wave behavior, achieving safe reception delay control with minimal redundancy, and ensuring stable reception within the non-interference range. This provides a time buffer for subsequent transmit tail energy modulation and spectrum rotation release.

[0072] S400 adjusts the transmit pulse envelope curve according to the avoidance time structure and performs tail power pre-drop processing before the transmit signal is turned off, so that the tail signal energy is introduced into the constructed time slot band and a diversion sequence for energy guiding attenuation is generated.

[0073] To further guide the wake wave energy to attenuate naturally within the avoidance time slot, a pre-decay processing of the tail power needs to be implemented by adjusting the transmit pulse envelope curve before the transmit signal is turned off, thereby generating a diversion sequence for energy release. The specific implementation steps are as follows:

[0074] Based on the established avoidance time structure, the minimum transition time required for guiding energy decay is determined, and a continuously decreasing power pre-adjustment segment is introduced at the end of the transmit pulse envelope. Using the end point of the avoidance time slot as a reference, a pre-fall window between 20 and 50 nanoseconds is derived. The length of this window must match the time required for the wake wave to decay naturally, ensuring a smooth transition of the energy peak to the start point of the slot rather than a direct cutoff. For example, if the avoidance time structure starts 140 nanoseconds after transmit shutdown, and the transmit wake wave requires 30 nanoseconds to complete power decay under natural conditions, the transmit signal enters the pre-fall segment at 970 nanoseconds (taking a 1 microsecond pulse width as an example) and finally shuts off completely at 1000 nanoseconds. During this time, the signal power decreases linearly or non-linearly from the peak value to the minimum value allowed by the system, avoiding abrupt energy termination that could cause reflection or interference.

[0075] When designing the pre-falling portion of the transmitted signal envelope curve, the response capability of the power amplifier used and the signal modulation characteristics should be considered to ensure that the envelope shape has control precision without causing modulation errors or spectral broadening. In specific implementations, exponential descent, linear segmented descent, or multi-segment slope composite descent can be selected, and the descent rate can be adjusted according to the system frequency characteristics. For example, for a 9.2 GHz carrier frequency radar, using an exponential descent method to control the power to decrease from 100% of the peak value to 0.1% takes approximately 32 nanoseconds, with the first 20 nanoseconds decreasing to 10% and the remaining portion completed in the last 12 nanoseconds. To achieve this envelope, a specific envelope level modulation curve can be set through the voltage control interface of the RF driver, while the signal strength is monitored by the steady-state monitoring of the power controller output threshold to ensure a smooth and fluctuation-free descent process. Within the descent range, sampling verification shows that the signal frequency stability fluctuation is less than 0.3 MHz and the phase jitter is less than 2 degrees, meeting the radar transmit link modulation requirements.

[0076] Simultaneously with the pre-fall processing, a diversion path needs to be established to effectively guide the wake energy into the avoidance time slot zone during the pre-fall process, rather than allowing it to stagnate in the main transmission path. To achieve this, an electromagnetic dissipation channel with frequency-selective attenuation characteristics should be configured in the physical structure. This channel is connected to the end of the main transmission path or a coupling branch, and can directionally absorb the low-to-medium intensity signal released during the power pre-fall phase. For example, a 3-5 dB adjustable attenuator can be connected in series at the end of the transmission chain, and then guided to the electromagnetic dissipation device via a directional coupler. During the power fall phase, this channel absorbs the wake energy, preventing it from reflecting back into the receiver chain or antenna structure and forming a backflip signal. In actual testing, this diversion structure achieved an energy absorption efficiency of over 83% during the wake phase, effectively reducing the residual interference voltage in the receiver path to below 1.1 mV. At the same time, a control mechanism synchronized with the time slot zone ensures that the diversion process only starts in the pre-fall interval, avoiding impact on the stability of the main signal transmission.

[0077] After the diversion operation is completed, the coupling consistency between the power drop curve and the avoidance time structure is verified by comparing and analyzing the diversion sequence with the original wake data. Specifically, after each launch cycle, a high-speed oscilloscope is used to capture the wake attenuation trajectory and compare it with the theoretically preset diversion time window to confirm whether the energy release completely covers the slot band time range. For example, if the preset slot band is 140 to 180 nanoseconds, the actual lower limit of energy time corresponding to the diversion sequence is 178 nanoseconds, indicating that the wake attenuation has been successfully guided into the target time interval. Furthermore, the frequency domain characteristics of the descent process are sampled using a spectrum analyzer to confirm that no new frequency sidelobes or nonlinear distortions are introduced during the pre-descent process. Measurement results show that the main frequency sidelobe suppression is better than 40 dB, indicating that the diversion sequence achieves both energy release and maintains good spectral purity. Thus, the pre-descent power processing of the launch tail segment based on the avoidance time structure is completed, providing the necessary time and energy channel support for subsequent spectrum rotation and folding energy dissipation.

[0078] The S500 utilizes a diversion sequence to drive a spectrum gating mechanism to perform frequency rotation switching around the main frequency bandwidth. Simultaneously, a reverse frequency sweep operation is applied during the spectrum rotation process, causing residual folded energy to be released in segments within the constructed ring spectrum channel, thereby achieving dynamic regulation and dissipation of spectrum folded energy.

[0079] To further dissipate the wake wave energy, the diversion sequence constructed in the previous step is used as the driving force. Through a combined mechanism of frequency rotation and reverse frequency sweeping, the residual folded energy is guided into the annular spectral channel, completing the dynamic energy release process. The specific implementation steps are as follows:

[0080] Based on the power attenuation trajectory and time distribution recorded in the diversion sequence, a rotating spectral window for frequency switching is constructed, and this window is periodically offset around the main frequency bandwidth boundary. The amplitude of the frequency rotation needs to cover the extended regions on both sides of the main transmission frequency band, generally selected between ±15 MHz and ±30 MHz of the main frequency band center frequency. Taking a center frequency of 9.2 GHz and a main frequency bandwidth of 200 MHz as an example, the frequency rotation operation will be carried out between 9.17 GHz and 9.23 GHz. In physical implementation, an adjustable frequency synthesizer is configured to drive the front-end frequency control element, so that the frequency control level completes small-amplitude switching at set time intervals. The step interval is recommended to be controlled within 200 kHz, and the rotation period is between 50 nanoseconds and 100 nanoseconds. Each frequency switching point uses the wake energy node defined in the diversion sequence as the trigger reference point to ensure that the rotation process always matches and adjusts around the energy release path, avoiding frequency offset and energy trajectory misalignment that could cause residual folded energy.

[0081] Based on the completed rotating frequency channel construction, a reverse frequency sweep operation is superimposed, creating a frequency sweeping wave structure that gradually contracts from the outside in, allowing for multiple alternating compressions and releases of the wake energy from high frequencies to the dominant frequency. This reverse frequency sweep process is the opposite of the forward frequency sweep; its scanning direction starts from the outermost frequency point of the rotating window and gradually converges towards the dominant frequency. The step unit is consistent with the rotating frequency switching, and a fine control method with a time interval of 5 to 10 nanoseconds is recommended. Each sweep step corresponds to a dynamic compression of the spectral energy density. The frequency modulator updates the RF synthesizer control voltage in real time, causing the wake signal to be rescheduled to the low-energy absorption region of the spectral passband. Taking a certain reverse frequency sweep as an example, when the frequency sweeps back from 9.23 GHz to 9.2 GHz, if a signal peak of 2.6 mV formed by the superposition of the tail wave is detected at 9.215 GHz, the frequency sweep dwell time is appropriately extended to 12 nanoseconds. After the energy is released at this frequency point, the next frequency band is entered, thereby achieving targeted dissipation of the energy burst area.

[0082] After completing the joint execution of frequency rotation and reverse frequency sweep, a closed and continuous energy dissipation band is formed in the spectral space by constructing a ring-shaped spectral channel. This channel is constructed as follows: multiple concentric rings of equal energy levels are built around the main frequency band, with a ring width of 2 MHz to 5 MHz. Each ring corresponds to a frequency rotation and sweep intersection region. When wake wave energy remains at any frequency point, the rotation and sweep mechanisms automatically transfer it to adjacent frequency rings, forming a continuous frequency energy migration trajectory. For example, if a wake wave still has a residual signal of 1.1 mV at 9.205 GHz, its energy will move clockwise into the 9.208 GHz frequency ring under the influence of the rotation mechanism. Before it completely dissipates at that point, it will continue to be swept and pushed into the 9.210 GHz frequency band, finally being released during the dwell period of the 9.212 GHz ring. In this way, energy does not accumulate at a certain frequency point, but is continuously guided and released by the frequency channel, achieving a dynamic and balanced dissipation process.

[0083] After the wake wave energy release task is completed in the annular spectrum channel, a time-frequency composite verification mechanism is used to confirm that all frequency rotation paths and reverse frequency sweep paths have covered the frequency range of all previously identified turnaround points, and that the corresponding time windows completely coincide with the wake wave energy trajectories in the diversion sequence. Specifically, after each frequency switching cycle, the residual energy in the current frequency band is sampled and compared. If no effective signal amplitude higher than the background level (e.g., less than 0.5 mV) is detected within the set time window, it is determined that the frequency point has been cleared of energy. All frequency points are verified sequentially. After confirming that there is no residual energy in the spectrum passband, the frequency rotation process terminates, and the frequency state is restored to the initial state of the next transmission cycle. Through this method, residual folded energy can be released in segments, dynamically controlled, and completely dissipated in the constructed annular spectrum channel, effectively improving the efficiency of wake wave clearance and establishing a clean spectrum foundation for the next radar transmit / receive switching cycle.

[0084] This invention introduces a power pre-decay process in the transmit tail segment to actively guide residual energy into a pre-constructed time slot band. Combined with frequency rotation and reverse frequency sweep mechanisms, it achieves point-by-point removal of folded energy within the ring spectrum channel, effectively preventing residual frequency components from superimposing interference in the main frequency band. This prevents the receiving channel from being falsely triggered before reaching the energy safety threshold. Furthermore, the diversion sequence constructed in this scheme is coupled with the dynamic spectrum control process, giving the energy release path both temporal adaptability and frequency domain discreteness. This ensures the stability of the transmit / receive switching window and significantly reduces the probability of triggering false alarm protection actions, achieving proactive prevention and control of tailwave interference and a comprehensive improvement in system operational stability.

[0085] This invention provides, for example Figure 2 The phased array radar antenna transmit / receive protection time test system shown includes a reverberation measurement module, an energy focusing analysis module, a receive avoidance control module, a transmit energy guidance module, and a spectrum dynamic adjustment module.

[0086] The aftereffect measurement module inserts a silent time window along the extended time axis of the transmitted pulse to form a silent zone for accommodating the aftereffect of the transmitted signal, constructs a time curve of the signal attenuation process, and plots the aftereffect scale line of the residual energy path based on the time curve.

[0087] The energy focusing analysis module performs a frequency-by-frequency scan within the main frequency bandwidth based on the aftereffect scale line, extracts the reversal and accumulation regions of residual energy in the spectral space, and records the relationship between the corresponding frequency points and time points, forming a list of reversal points containing the energy reversal locations;

[0088] The receive avoidance control module constructs a time slot band on the time axis to delay the reception operation based on the frequency and time data recorded in the turnaround point list. This delays the reception start action until the time interval after all the residual energy has decayed, forming an avoidance time structure for transmit / receive switching.

[0089] The transmission energy guidance module adjusts the transmission pulse envelope curve according to the avoidance time structure and performs tail power pre-decline processing before the transmission signal is turned off, so that the tail signal energy is introduced into the constructed time slot band and a diversion sequence for energy guidance attenuation is generated.

[0090] The spectrum dynamic control module uses a diversion sequence to drive a spectrum gating mechanism to perform frequency rotation switching around the main frequency bandwidth. At the same time, a reverse frequency sweep operation is applied during the spectrum rotation process, so that the residual folded energy is released in segments in the constructed ring spectrum channel, thereby realizing the dynamic control and dissipation of spectrum folded energy.

[0091] The phased array radar antenna transmit / receive protection time test method provided in this embodiment of the invention is implemented by the aforementioned phased array radar antenna transmit / receive protection time test system. For details of the specific methods and procedures of the phased array radar antenna transmit / receive protection time test system, please refer to the embodiment of the aforementioned phased array radar antenna transmit / receive protection time test method, which will not be repeated here.

[0092] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for testing the transmit-receive protection time of a phased array radar antenna, characterized in that, The method comprises the following steps: S100, a mute time window is inserted along the tail of the transmission pulse time axis to form a mute area for accommodating the tail wave of the transmission signal, a time curve of signal attenuation process is constructed, and a residual energy path scale line is drawn based on the time curve; Step S100 specifically comprises: The time axis is extended along the tail of the transmission pulse signal, and a mute time window is inserted at the start position of the extended section, so that the receiving front end remains closed in the mute area and captures the natural attenuation waveform of the tail wave; In the mute time window, a high-sensitivity probe is used to sample and record the signal amplitude change trajectory at a high time resolution, and an attenuation waveform curve of the tail wave signal is drawn; According to the attenuation waveform, the energy attenuation rate is calculated in sections, the time points below the peak percentage threshold are extracted and marked to form an attenuation characteristic scale line; Based on the key time points of the attenuation characteristic scale line and the spatial propagation reflection characteristics, a residual energy propagation path trajectory is constructed, and a time-space mapping diagram of the energy path is formed through multi-angle monitoring nodes; S200, based on the residual scale line, a frequency-by-frequency scan is performed in the main frequency bandwidth range, the residual energy is extracted in the backfolding and gathering area in the frequency spectrum space, and the relationship between the corresponding frequency points and time points is recorded to form a list of turning points containing energy backfolding positions; S300, according to the frequency point and time point data recorded in the list of turning points, a time gap band for delay receiving operation is constructed on the time axis, the receiving start action is delayed to the time interval after the residual energy is completely attenuated, and an avoidance time structure for transceiver switching is formed; S400, according to the avoidance time structure, the transmission pulse envelope curve is adjusted, the tail power pre-decrease processing is implemented before the transmission signal is turned off, the tail signal energy is introduced into the constructed time gap band, and a drainage sequence for energy guided attenuation is generated; S500, the drainage sequence is used to drive the frequency spectrum gating mechanism to perform frequency rotation switching around the main frequency bandwidth, and a reverse frequency sweeping operation is applied in the frequency spectrum rotation process, so that the residual folded energy is released in sections in the constructed ring-shaped frequency spectrum channel, and dynamic regulation and dissipation of the frequency spectrum folded energy are realized.

2. The phased array radar antenna transmit-receive protection time test method of claim 1, wherein, The length of the mute time window is set to be less than the time interval of the pulse period, the rising edge response time of the high-sensitivity probe is less than the attenuation characteristic time of the transmission signal, and multiple electromagnetic wave reflection monitoring nodes are arranged in the transmission path to realize multi-angle synchronous observation of the tail wave energy, so as to ensure the corresponding accuracy of the residual scale line in the time axis and the space path.

3. The phased array radar antenna transmit-receive protection time test method of claim 1, wherein, Step S200 comprises: According to the constructed residual scale line, the main frequency bandwidth range is selected as the scanning target, the frequency band is divided into equally spaced scanning frequency points, and low-power detection waves are transmitted one by one to detect energy rising mutations; The detected frequency points are classified according to the energy intensity and time correspondence, a binary data structure of frequency and time is established, and an energy density index is calculated; The energy data of all frequency points are sorted and filtered, isolated noise interference signals are removed, and energy gathering areas with concentrated intensity and continuous frequency distribution are selected; The frequency and time boundary information of the energy accumulation area is used to generate a list of turn-back points, record the frequency interval, energy threshold level, decay time period, and residual echo scale mapping interval, which are used for subsequent avoidance time structure construction.

4. The phased array radar antenna transmit-receive protection time test method of claim 3, wherein, Step S300 includes: The frequency interval and energy accumulation time period recorded in the list of turn-back points are extracted as the starting basis of the reception action delay window, and a safety buffer time is added after the accumulation time period to determine the safe reception starting point; The delay windows corresponding to each frequency interval are uniformly mapped on the time axis to establish delay time slices and merge overlapping intervals to form a continuous time slot band; The reception control logic is adjusted according to the formed time slot band, the reception start action is delayed until the end of the slot band, and a reception window is extended after it to ensure data integrity; The time slot band is fine-tuned cycle by cycle based on the real-time collected energy accumulation data in the continuous pulse process to maintain the dynamic consistency of the avoidance time structure and the tail wave behavior.

5. The phased array radar antenna transmit-receive protection time test method of claim 4, wherein, When adjusting the reception start action, the delay control signal is synchronized and calibrated with the transmission off signal, the reception start time error is limited within the preset time range through a high-precision timing control unit, and the reception channel is kept closed in the time slot band to prevent tail wave energy interference, realizing stable triggering of the reception action after the energy completely decays.

6. The phased array radar antenna transmit-receive protection time test method of claim 5, wherein, Step S400 includes: The transition time for guiding energy decay is determined according to the constructed avoidance time structure, a continuously declining power pre-adjustment section is introduced at the end of the transmission pulse envelope to smoothly transition the energy to the start point of the time slot band; The pre-decline part of the transmission envelope curve is designed in combination with the power amplifier response capability and signal modulation characteristics to control the power to gradually decline from the peak value to the minimum value to avoid reflection interference; A frequency-selective decay channel is established during the pre-decline process to guide the tail wave energy into the time slot band through a directional coupler and complete energy absorption; After the drainage operation is completed, the drainage sequence and tail wave data are compared to verify the coupling consistency of the power decline curve and the avoidance time structure and confirm the spectral purity.

7. The phased array radar antenna transmit-receive protection time test method of claim 6, wherein, During the power pre-decline process, the energy guiding channel composed of an adjustable attenuator and a directional coupler realizes directional absorption of tail wave energy, the attenuator output end is connected to an electromagnetic dissipative device, which is used to absorb medium and low intensity signals during the power decline stage and prevent energy reflection to the transmission path, ensuring that the tail wave energy is completely attenuated in the time slot band and maintaining spectral stability.

8. The phased array radar antenna transmit-receive protection time test method of claim 7, wherein, Step S500 includes: A rotating spectral window is constructed according to the power decay trajectory and time distribution law in the drainage sequence, and periodic shifts are made on both sides of the main frequency bandwidth to form a frequency switching path; An inverse sweep operation is superimposed in the rotating spectral window to form a sweep structure that shrinks layer by layer from the outside to the inside of the spectral space to guide the tail wave energy to release towards the main frequency direction; After completing the frequency rotation and inverse sweep, the frequency switching path and the sweep trajectory are connected into a closed energy dissipation band through the construction of a ring-shaped spectral channel to realize segmented energy release; After the end of spectral energy release, the energy emptying in the spectral ring passband is confirmed through a time-frequency composite verification mechanism and the initial state of the next transmission cycle is restored.

9. A phased array radar antenna transmit-receive protection time test system for implementing the phased array radar antenna transmit-receive protection time test method of any of claims 1-8, characterized by, The application comprises a residual echo measurement module, an energy focusing analysis module, a receiving avoidance control module, a transmitting energy guiding module and a spectrum dynamic regulation module. The residual echo measurement module inserts a silence time window along the tail of the transmitting pulse, forms a silence area for accommodating the residual echo of the transmitting signal, constructs a time curve of the signal attenuation process, and draws a residual echo scale line of the residual energy path based on the time curve. The energy focusing analysis module performs a frequency-by-frequency scan within the main frequency bandwidth based on the residual echo scale line, extracts a backfolding gathering area of the residual energy in the spectrum space, records the relationship between the corresponding frequency point and the time point, and forms a backfolding point list containing the energy backfolding position. The receiving avoidance control module constructs a time gap band of the delayed receiving operation on the time axis according to the frequency point and time point data recorded in the backfolding point list, delays the receiving start action to the time interval after the residual energy is completely attenuated, forms an avoidance time structure for the transmitting-receiving switching, and adjusts the transmitting pulse envelope curve according to the avoidance time structure. The transmitting energy guiding module implements a tail power pre-decrease process before the transmitting signal is turned off, introduces the tail signal energy into the constructed time gap band, and generates a guiding sequence for the energy guiding attenuation. The spectrum dynamic regulation module drives the spectrum gating mechanism to perform a frequency rotation switching around the main frequency bandwidth by using the guiding sequence, simultaneously applies a reverse frequency sweep operation in the spectrum rotation process, makes the residual folded energy released in segments in the constructed ring-shaped spectrum channel, and realizes the dynamic regulation and dissipation of the spectrum folded energy.

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