A low-power-consumption high-power-density active phased array radar system

Abstract

The present application relates to active phased array radar system control technical field, disclose a kind of low-power high power density active phased array radar system, comprising: system controller logical division aperture T / R component is sentry subsystem and wake-up subsystem;Sentry subsystem is configured to adopt floodlight emission combined with digital beam forming parallel narrow-beam reception, and run moving target indication (MTI) logic processes coherent pulse train echo to suppress clutter, to detect moving target and determine its azimuth information;Wake-up subsystem is then configured to perform high-power narrow-beam confirmation according to azimuth information, the present application solves the information exchange problem between wide-area low-power monitoring and instantaneous high-precision aiming by transmitting and receiving asymmetric mechanism, so that sentry subsystem obtains receiving high resolution under floodlight emission, provides azimuth guidance for wake-up subsystem, avoids secondary search.

Description

Technical Field

[0001] This invention relates to a low-power, high-power-density active phased array radar system, belonging to the field of active phased array radar system control technology. Background Technology

[0002] Active phased array radar systems, with their high power density and beam agility, play a crucial role in radio detection and location. Their core capability lies in forming a high-gain narrow beam through the coherent superposition of numerous transceiver (T / R) components to perform long-range detection and precise target tracking. In current technological practices, whether performing wide-area search tasks or tracking specific targets, the system typically relies on the same complete set of aperture resources. This design, where search and tracking functions share the same resource pool, inherently limits operational efficiency when operating on platforms with strict power consumption and heat dissipation constraints. In actual operation, the vast majority of the radar system's operating time is consumed in wide-area search. In the search of wide-area airspace, where no targets exist for most of the time, existing systems must illuminate with near-peak power for each beam pointing during the search phase to ensure the detection of potential targets with the smallest radar cross-section at the maximum design range. This results in the system's power consumption being almost the same during the high proportion of air search time as it is when performing high-value effective tracking tasks. This binds the system's average power consumption to the requirements of its search function, which in turn is constrained by the peak power requirements under worst-case conditions. This coupling between search power consumption and tracking performance restricts the application of high-performance radar on power-sensitive platforms.

[0003] At the control logic level, existing technologies also have limitations. Some low-power radar designs focus on refining time-domain control rather than aperture resource management in phased array systems. For example, Chinese invention patent CN1906499B discloses a small-size, low-power, short-range radar and its control method that arbitrarily changes the delay between transmission and reception using high time resolution. The core of this patent lies in using a direct digital synthesizer (DDS) to control the time-domain delay between the transmission and reception trigger signals, thereby achieving high range resolution. However, this design approach is based on a traditional symmetrical pulse transmission and reception system, and its technological contribution lies in time resolution, i.e., how to precisely control the range gate. It does not address, nor can it resolve, the core contradiction of spatial resolution in phased array radar that this invention focuses on: how to obtain high-precision target azimuth information instantaneously while maintaining low power consumption through floodlight transmission. Therefore, this solution does not provide a way to decouple wide-area search power consumption from aperture. Effective resource scheduling mechanisms cannot resolve the information connection barrier between detection and targeting. Furthermore, a common design configuration in radar system design assumes that the system's receiving beam pattern should be symmetrical to its transmitting beam pattern. For example, when designing a wide-area search system, if floodlight transmission is used, the receiving system will also be configured with a matching floodlight reception. This symmetrical design creates a physical contradiction between wide-area coverage and instantaneous high spatial resolution. Under traditional floodlight systems, achieving wide-area coverage comes at the cost of sacrificing spatial resolution, making it impossible to instantly distinguish the precise location of targets within a wide area at the receiver. This low-resolution characteristic creates an inherent information connection barrier between the two consecutive actions of target detection and target targeting. The system is either forced to revert to a high-power, narrow-beam point-by-point scanning method or still needs to perform a costly secondary search after target detection, resulting in additional performance overhead.

[0004] Therefore, the technical problem to be solved by this invention is how to design a radar system operating architecture that can achieve low-power wide-area surveillance while maintaining high power density tracking capability, and solve the information connection problem between wide-area detection and narrow-beam precise handover. Summary of the Invention

[0005] This invention provides a low-power, high-power-density active phased array radar system. Its main purpose is to solve the problems of coupling wide-area search power consumption with high-power-density tracking performance, as well as the information connection barrier between floodlight detection and narrow-beam aiming in the prior art.

[0006] To achieve the above objectives, the present invention provides a low-power, high-power-density active phased array radar system, comprising:

[0007] The phased array radar consists of aperture T / R modules and a system controller. The system controller is configured to: dynamically divide the aperture T / R modules into a sentinel subsystem and a wake-up subsystem; instruct the sentinel subsystem to perform a floodlight transmission operation to illuminate a wide-area surveillance airspace; and in the receiving time slot immediately following the floodlight transmission, instruct the signal processor of the sentinel subsystem to perform digital beamforming operations on the received data from the aperture T / R modules to form N receiving narrow beam clusters in parallel within the wide-area surveillance airspace.

[0008] The system controller is also configured to: instruct the sentinel subsystem to transmit a set of coherent pulse trains; and the signal processor of the sentinel subsystem employs a lightweight moving target indication (MTI) logic to coherently process the echoes of the coherent pulse trains on the N receiving narrow beam cluster channels.

[0009] The wide-area presence detection operation rules of the sentinel subsystem are set as follows: only if the presence detection occurs on the 1st day after the lightweight moving target indication (MTI) logic processing. When the receiving narrow beam channel detects energy indicated as a moving target, it is determined that a potential target has been detected, and the first narrow beam channel... The system receives a narrow beam channel and determines its preset direction as the high-precision azimuth information of a potential target; and in response to wide-area presence detection, it activates the wake-up subsystem to operate at high power density and instructs it to form a pencil beam, setting the direction of the pencil beam only to be determined by the first... High-precision azimuth information determined by a narrow beam channel.

[0010] Preferably, the system controller is configured such that: when the signal processor of the command sentry subsystem uses the lightweight moving target indication (MTI) logic, it only performs double-pulse cancellation and triple-pulse cancellation operations; and commands the signal processor of the wake-up subsystem to execute the full-function measurement logic consisting of pulse compression and Doppler processing.

[0011] Preferably, the system controller is further configured to: send the received data of the sentinel subsystem in parallel to an interference covariance analysis logic unit during the operation of the sentinel subsystem; the interference covariance analysis logic unit is configured to: analyze the spatial correlation of the received data and determine whether there is an interference source and its direction of arrival; and when the interference source and its direction of arrival are determined, the system controller is configured to: calculate a set of receiving beamforming weights that form a receiving null in the direction of arrival of the interference source, and apply the receiving beamforming weights to the sentinel subsystem.

[0012] Preferably, the sentinel subsystem comprises 70% to 95% of the aperture T / R components, while the wake-up subsystem comprises 5% to 30% of the aperture T / R components; the sentinel subsystem and the wake-up subsystem operate asynchronously in timing.

[0013] Preferably, the system controller is further configured to: set an energy detection threshold for the wide-area presence detection operation rules of the sentinel subsystem; send the received data to a background processing unit in parallel; the background processing unit is configured to: perform incoherent long-time integration on the subthreshold signals in the received data that are below the energy detection threshold, and generate a static clutter background map; and the energy detection threshold is configured to be spatially adjusted according to the static clutter background map.

[0014] Preferably, the system controller is further configured to: after the wake-up subsystem performs target parameter measurement on the high-precision azimuth information, determine the signal-to-noise ratio of the measurement; and when the determination is that the signal-to-noise ratio is lower than a preset confirmation threshold, the system controller is configured to immediately instruct the sentinel subsystem and the aperture T / R component of the wake-up subsystem to perform logical merging, and perform an upgrade confirmation on the high-precision azimuth information using the full aperture and peak power density of the phased array radar.

[0015] Preferably, the system controller is further configured to: after the wake-up subsystem confirms the potential target and establishes a target track; transfer the target track tracking task to a tracking subsystem dynamically composed of aperture T / R components; and enable the sentinel subsystem and the wake-up subsystem to resume their wide-area presence detection and on-demand activation operating logic.

[0016] Preferably, the sentinel subsystem is further configured to calculate the signal-to-noise ratio margin of potential targets in wide-area presence detection; and the system controller is configured to: select a resource configuration scheme from a preset resource level library based on the signal-to-noise ratio margin; and instruct the wake-up subsystem to use a predetermined power aperture resource when using a pencil beam, according to the resource configuration scheme.

[0017] Preferably, the system controller is further configured to: after the wake-up subsystem successfully confirms the potential target, acquire the high-precision measurement parameters measured by the wake-up subsystem and the low-precision observation parameters observed by the sentinel subsystem at the time of triggering; perform long-term statistical analysis based on the information residual between the high-precision measurement parameters and the low-precision observation parameters, and determine whether there is a systematic drift in the operating parameters of the sentinel subsystem, wherein the systematic drift... By analyzing information residuals Perform long-term integral statistics To determine, For the first Secondary information residual, The number of events is used for statistical analysis; and based on the judgment results of systematic drift, the detection threshold and beamforming parameters of the sentinel subsystem are calibrated.

[0018] Preferably, the system controller is configured to instruct the aperture T / R component in the sentinel subsystem to operate at a power level 5% below its peak power; and to instruct the aperture T / R component in the wake-up subsystem to operate at 100% of its peak power.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. By logically and dynamically dividing the aperture T / R component of the phased array radar into a sentinel subsystem and a wake-up subsystem, and configuring an operating procedure for the sentinel subsystem with different transmit and receive beam patterns, this design enables the sentinel subsystem to perform low-power wide-area floodlight transmission to cover the surveillance airspace. In the subsequent receive time slot, it can utilize the aperture resources of its T / R component to generate multiple narrow receive beam clusters covering the same wide area in parallel through digital beamforming logic. Therefore, while maintaining low-power surveillance, the sentinel subsystem itself has the ability to instantly obtain the high-precision azimuth of potential targets, solving the information handover problem between wide-area detection and precision aiming.

[0021] 2. Based on the real-time high-precision azimuth information provided by the sentinel subsystem, the wake-up subsystem, once activated by the controller, does not need to perform any form of secondary search or sector scan. The high-power density pencil beam of the wake-up subsystem is configured to point only to that precise azimuth and perform a one-time fine target parameter measurement. This precise guidance working mode, from low-power detection to high-power confirmation, enables high-power resources to be truly called up on demand, avoiding the energy and time consumption caused by the additional search that traditional wide-beam detection systems must perform after the target is detected due to azimuth ambiguity.

[0022] 3. In operation, the sentinel subsystem of this scheme deeply reuses the transmission and reception functions of the same set of T / R components. During transmission, it uses this set of components to form a low-power wide beam for space illumination; during reception, it uses the large aperture characteristics of the same set of components to generate a high-resolution narrow beam cluster through digital beamforming logic for accurate direction finding. This heterogeneous design allows the system to simultaneously carry out the dual tasks of low-power illumination and high-precision direction finding without changing the hardware configuration, thus improving the efficiency of system resource utilization. This asynchronous partitioning mechanism of sentinel and wake-up, combined with the asymmetric operation procedure of the sentinel subsystem, establishes a sustainable low-power active surveillance operating state for the active phased array radar system. In this state, the system is freed from the traditional radar operation mode that must rely on periodic full-power scanning, and instead maintains continuous coverage of the entire surveillance airspace with lower average power consumption, while inherently retaining the ability to perform instantaneous high-power density confirmation of the azimuth of any suspicious target. This achieves the effective coexistence of wide-area surveillance capability and focused detection capability on a power-constrained platform. Attached Figure Description

[0023] Figure 1 This is a diagram showing the sentinel wake-up function logic and closed-loop data flow of the radar system of the present invention;

[0024] Figure 2 This is a calibration diagram showing the relationship between the wake-up resource level library and the signal-to-noise ratio margin in this invention;

[0025] Figure 3 This is a schematic diagram of the high-level implementation architecture of the Sentinel Wake-up Twin System of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the scope of protection of the invention.

[0027] This invention provides a low-power, high-power-density active phased array radar system, applicable to platforms with limited power consumption and heat dissipation, such as unmanned aerial vehicles, portable detection devices, or distributed aperture nodes. These platforms impose strict limitations on the system's average operating power consumption while simultaneously requiring high-power-density, precise detection and positioning capabilities under specific conditions. The hardware foundation of this system includes an active phased array radar antenna array composed of numerous aperture transceiver (T / R) components, and a system controller serving as the system's control hub. The system controller is typically implemented using a field-programmable gate array (FPGA) or a dedicated signal processing chip, and its internal... The control procedures used to execute the operating logic of this invention have been optimized. The core function of the system controller lies in its configuration to dynamically and asymmetrically partition the physical resources of the aperture T / R components. During system operation, it dynamically and logically divides the physical aperture T / R components into a sentinel subsystem and a wake-up subsystem. This logical partitioning is not a physical division, but is achieved by the system controller sending different control commands (including power status, phase weighting, and operating timing) to different T / R component addresses. In a typical system configuration, the system controller can be configured to logically allocate 70% to 95% of the aperture T / R components. The remaining 5% to 30% is allocated to the sentinel subsystem, while the wake-up subsystem is designated as the sentinel subsystem. These two logical subsystems are configured to operate asynchronously, meaning the wake-up subsystem remains inactive and dormant most of the time, activating only upon receiving a specific trigger from the sentinel subsystem. The sentinel subsystem's operating procedure addresses the technical challenge of balancing wide-area coverage with instantaneous high resolution requirements. To this end, the system controller is configured to instruct the sentinel subsystem to execute an asymmetric transmit / receive operating mechanism: during the transmit phase, the system controller instructs the aperture T / R component of the sentinel subsystem to operate in a low-power state, for example, below its peak power. The system applies 5% of the power to these components and applies a coarse phase weighting to the synthesized transmit beam, causing it to form a floodlight transmission operation. This floodlight beam illuminates a predetermined wide-area surveillance airspace with low power density. Immediately following the floodlight transmission, in the receive time slot, the system controller performs a receive path multiplexing operation. It instructs the signal processor of the sentinel subsystem (e.g., the digital beamforming (DBFN) logic unit within the FPGA) to perform digital beamforming operations in parallel on the acquired received data, utilizing the large-aperture receiving advantage of the same set of aperture T / R components. Essentially, this operation involves the signal processor multiplying the same set of raw received data in parallel by... Groups (e.g.) Different weighting coefficients are used to instantaneously and in parallel form in the digital domain. A narrow beam cluster for receiving, this The receiving narrow beams are closely arranged in space, together forming a complete and high-resolution coverage of the wide-area surveillance airspace.

[0028] Furthermore, to address the masking effect of strong stationary clutter (such as ground and building echoes) on low-energy moving targets (such as small UAVs) during detection (especially in low-altitude or ground applications), the sentinel subsystem does not simply perform energy detection; the system controller is configured to instruct the sentinel subsystem to emit a coherent pulse train, such as three consecutive phase-controlled pulses, when performing floodlight emission; correspondingly, the signal processor of the sentinel subsystem is instructed to... On each channel of the parallel receiving narrow beam cluster, a lightweight moving target indication (MTI) logic is employed to coherently process the echoes of the coherent pulse train. The lightweight MTI logic is specifically configured to perform only computationally inexpensive three-pulse cancellation operations, for example, for the first... One receiving narrow beam channel, its MTI processing output It consists of three consecutive echo pulses received on this channel. , , go through The coherent subtraction operation yields the following formula: , , For three consecutive received echo signals; this operation makes the signal from stationary clutter (its The echo energy of the target approaches zero after coherent subtraction, while the echo energy from the moving target (whose echo energy decreases due to phase change) is much higher. The energy (if there are differences) is preserved; the system controller is also configured to instruct the sentinel subsystem to use at least two different pulse repetition frequencies within a complete monitoring cycle when emitting the coherent pulse train. and During alternating or grouped transmissions, the signal processor of the sentry subsystem is configured to respectively... Corresponding echo pulse train and The corresponding echo pulse trains independently execute the lightweight moving target indication (MTI) logic, and in the wide-area presence detection operation rules, perform an OR logic decision on the output energy of the two independent MTI logic processing channels, that is, if the output energy of either PRF channel exceeds the MTI output threshold... At any given time, it is determined that a potential target has been detected; based on the above mechanism, the wide-area presence detection operation rules of the sentinel subsystem are set as follows: the signal processor only indicates the MTI logic processing for lightweight moving targets. The output energy of each channel is used for energy detection and decision; only when the output energy of the first channel is determined... One (e.g.) The system determines that a potential target has been detected only when the residual energy indicating a moving target on the narrow beam channel exceeds a preset energy detection threshold. At this point, the system controller completes one information handover; it does not require any secondary search but directly transmits the data. The preset direction (a high-resolution angle value) of a receiving narrow beam channel is used to determine the high-precision azimuth information of a potential target.

[0029] The wake-up subsystem is activated based on the high-precision azimuth information provided by the sentinel subsystem; the system controller is configured to activate only in response to the sentinel subsystem (e.g., at the [timeframe]). The wake-up subsystem is activated to operate at high power density only when wide-area presence detection is triggered by the first channel (channel number 1), and is instructed to operate at 100% peak power (e.g., by the remaining 10% of the T / R components). The controller allocates the aperture resources of the wake-up subsystem to instantaneously form a high-gain, high-power-density pencil beam, and the direction of this pencil beam is uniquely and precisely set to be determined by the first channel (channel number 1). The receiving narrow beam channel determines the high-precision azimuth information (i.e., the direction of beam 137); the wake-up subsystem then performs a refined measurement on this precise direction, and its signal processor is instructed to execute a full-function measurement logic consisting of pulse compression and Doppler processing (e.g., full-function FFT operation) to obtain the target's precise parameters (such as high-precision range, velocity, etc.); to further improve the system's operational stability in complex environments, the system controller of this invention can also integrate multiple adaptive procedures; for example, the system controller can be configured to send its received data in parallel to an interference covariance analysis logic unit when the sentry subsystem is running; this logic unit determines whether the received data is spatially correlated between array elements by analyzing the spatial correlation between the received data. The system controller is configured to detect the presence of a targeted interference source and its direction of arrival. When an interference source is identified, the system controller autonomously calculates a set of receiving beamforming weights that create a receiving null in the direction of arrival of the interference source. These weights are then applied to the digital beamforming operation of the sentinel subsystem, thereby maintaining the sentinel subsystem's low-power operation while autonomously suppressing interference. Simultaneously, to address system parameter drift caused by environmental changes (such as temperature) or device aging during detection, the system controller can also be configured to execute a closed-loop self-calibration logic. Specifically, after the wake-up subsystem successfully confirms a potential target, the system controller is configured to simultaneously acquire high-precision measurement parameters (e.g., precise azimuth) obtained by the wake-up subsystem. ), and the sentinel subsystem at the time of triggering, i.e. The observed parameters observed in the first channel, for example, the first channel. nominal orientation of the channel The controller is based on the information residual between high-precision measurement parameters and observation parameters. Long-term statistical analysis was conducted, and the information residuals were analyzed. Long-term integral statistics are used to determine whether systematic drift exists. ,in, For the first Secondary information residual, The number of events for statistical analysis; and based on systematic drift. Based on the judgment results, the receiving beamforming parameters of the sentinel subsystem are autonomously and minutely calibrated.

[0030] To further enhance the detection stability of the sentinel subsystem in complex environments, the system controller can also be configured to execute a background processing procedure based on received data stream multiplexing; under this procedure, the signal processor of the sentinel subsystem is configured to parallel process its received data from... A copy of each narrow beam cluster channel, which can be received before or after the execution of the Lightweight Moving Target Indication (MTI) logic, is sent to a background processing unit; the background processing unit is configured to process received data below the energy detection threshold or the MTI output threshold. The subthreshold signal undergoes incoherent long-time integration; specifically, the unit maintains an integrated energy value for each angle-range resolution cell in the wide-area surveillance airspace by averaging the subthreshold echo energy falling into the cell over a long period (e.g., tens of seconds or minutes); since moving targets have short dwell times within a resolution cell, their energy is smoothed out under long-time integration, while stationary clutter sources such as mountains and building clusters persist, and their energy gradually accumulates through integration; the background processing unit generates and periodically updates a static clutter background map, for example, every minute, reflecting the spatial distribution of stationary clutter energy within the surveillance airspace; and the energy detection threshold or... used by the sentry subsystem for wide-area presence detection... Instead of being a globally fixed value, it is configured to dynamically and spatially adapt to the static clutter background map. In angle-distance cells that are indicated as strong clutter regions in the static clutter background map, the corresponding detection threshold is automatically raised, while in low clutter regions, the threshold is kept low, thereby achieving a balance between clutter suppression and target detection sensitivity in different regions.

[0031] The background processing unit is also configured to, while performing incoherent long-time integration on subthreshold signals below the energy detection threshold in the received data to generate the static clutter background map, simultaneously perform long-time coherent processing on the same set of subthreshold signals at each angle-range unit to estimate the power-weighted spectral width of their Doppler spectra. The background processing unit is based on the spectral width Does it exceed a preset non-static threshold? The system controller is then configured to generate and update a dynamic clutter feature map, which characterizes the presence of non-stationary clutter sources such as weather or sea clutter in the monitored airspace. The system controller is further configured to adaptively adjust the MTI logic of the sentinel subsystem based on the static clutter background map and the dynamic clutter feature map. Specific adjustment methods include: in areas where the dynamic clutter feature map indicates non-stationary clutter, adjusting the cancellation order of the lightweight moving target indication MTI logic from three pulses to two pulses, or independently increasing the MTI output threshold in that area. The system controller is configured to implement a hierarchical resource allocation mechanism to ensure that even when facing targets at extremely long ranges or with extremely low radar cross-sections (RCS), such targets may trigger the sentinel subsystem, but the wake-up subsystem still has detection capability despite insufficient signal-to-noise ratio. This mechanism works as follows: after the wake-up subsystem performs target parameter measurements on the high-precision azimuth information, the controller makes a decision on the measured signal-to-noise ratio (SNR). When the SNR is determined to be below a preset confirmation threshold, the system controller does not immediately discard the target. Instead, it is configured to immediately instruct the sentinel subsystem and the wake-up subsystem to logically merge their aperture T / R components and perform an upgrade confirmation on the high-precision azimuth information using the full aperture (100% T / R component) and peak power density of the phased array radar. This allows the system to maintain low-power operation during normal operation while retaining the peak detection performance required to deal with specific threats.

[0032] Example 1: In a specific application scenario, an unmanned aerial vehicle (UAV) equipped with the radar system of this invention performs tasks on a terrain with complex mountainous terrain under power-constrained conditions. The objective challenge of wide-area surveillance within a sector lies in ensuring the detection of low-altitude, low-radar-cross-section (RCS) moving targets amidst strong, large-area ground clutter while maintaining low average power consumption to extend UAV endurance. Upon system startup, the system controller configures 90% of the aperture T / R modules as sentinel subsystems and 10% as wake-up subsystems, keeping the latter inactive. The sentinel subsystems then enter their low-power active surveillance mode, with their controller instructing 90% of the T / R modules to perform a floodlight transmission operation at 5% below peak power. This transmitted beam covers the entire area, including mountains. Wide-area surveillance airspace; in the immediate following receive time slot, the sentry subsystem's signal processor utilizes the received data acquired by the 90% aperture T / R module to perform digital beamforming operations in parallel. Generated within the wide-area surveillance airspace Each of the 256 receiving narrow beam clusters is used for receiving. At the same time, since the sentry subsystem transmits a coherent pulse train, the signal processor then applies lightweight moving target indication (MTI) logic, i.e., three-pulse cancellation operation, in parallel to the echo data on the channels of these 256 receiving narrow beam clusters. Under this coherent processing, the strong clutter echoes from the vast mountains (stationary targets) are suppressed in all 256 channels due to coherent subtraction, and the output energy after MTI processing is lower than the preset energy detection threshold.

[0033] During this operational period, a low RCS moving target entered the wide-area surveillance airspace and happened to be located at the [missing information - likely a location name]. Within the coverage area of ​​the narrow beam receiver; although the original echo energy of the target is much lower than the clutter echo of the mountain, due to its motion, there is a phase change between the echo and the coherent pulse train, resulting in non-zero residual energy after the lightweight moving target indication MTI logic processing on channel 137. This residual energy exceeds the energy detection threshold; the wide-area presence detection operation rule of the sentinel subsystem is triggered, and the system controller determines that a potential target has been detected in the narrow beam receiver channel 137, and immediately determines the preset direction of the channel (a high-resolution angle value) as the high-precision azimuth information of the potential target; in response to this detection, the system controller immediately activates the wake-up subsystem (10% of the T / R component) to operate at 100% peak power. The wake-up subsystem is instructed to form a high-power-density pencil beam, and the direction of this pencil beam is precisely set to the high-precision azimuth information determined by the narrow beam channel of receiver number 137. The wake-up subsystem performs a fine-grained target parameter measurement only at this azimuth. Its signal processor runs full-function measurement logic (pulse compression and Doppler processing) to obtain the fine parameters of the low RCS moving target, and then hands over the target track to a dynamically configured tracking subsystem. After that, the wake-up subsystem immediately returns to the inactive state, while the sentinel subsystem resumes its low-power wide-area presence detection operation logic. The entire detection and confirmation process avoids high-power full-space scanning, and the system's high-power-density resources are only instantaneously called upon when the moving target triggers high-precision azimuth information.

[0034] Example 2: To objectively quantify the operational performance of the radar system of the present invention in terms of power consumption and detection capabilities, the following comparative experiment was conducted. The experimental platform consisted of an active phased array radar prototype containing 1000 aperture T / R modules. The prototype was uniformly controlled by an FPGA-based system controller, which could be configured to run different detection modes. The experimental environment was constructed using a target simulator and a clutter generator. The clutter generator was used in the monitored airspace... A strong stationary clutter signal with a signal-to-noise ratio (CNR) of 40 dB is injected in the azimuth direction to simulate strong ground echoes. The target simulator is in the monitored airspace at + A moving target signal with a signal-to-noise ratio (SNR) of 15 dB was injected azimuthally. The total monitoring time of the experiment was set to 600 seconds. The moving target signal appeared at the 300-second mark of the experiment and lasted for 10 seconds. For performance comparison, control group A, control group B, control group C, and the prototype of this invention were set up. All four groups of experiments were run on the same experimental platform and environment. Their operation configurations are as follows: Control group A: Traditional narrow beam scanning method was used. The system controller instructed all 1000 T / R components to operate at 100% peak power, and the entire monitoring airspace was covered by beam step scanning. Control group B: Symmetric floodlight method was used. The system controller instructed all 1000 T / R components to perform floodlight transmission at 5% low power, and matched floodlight reception was used during reception. The signal processor only executed energy detection logic. Control group C: Asymmetric transmit and receive method without MTI was used. The system controller instructed 900 T / R components (90% aperture) to perform floodlight transmission at 5% low power, and digital beamforming was performed during reception to generate A narrow beam cluster is received, but the signal processor only performs energy detection logic on the narrow beam channel and is configured to trigger a wake-up subsystem consisting of 100 T / R components (10% aperture) when energy is detected; In the prototype of this invention: using the complete operating mode of this invention, the system controller instructs 900 T / R components (90%) to form a sentinel subsystem, which performs coherent pulse train floodlight transmission at 5% low power and performs digital beamforming generation during reception. A narrow beam cluster was received, and lightweight moving target indication (MTI) logic (three-pulse cancellation) was performed on all channels. 100 T / R components (10%) were instructed to form a wake-up subsystem, which remained inactive until activated to perform a pencil beam confirmation at 100% peak power upon detecting high-precision azimuth information of a moving target after processing the sentinel subsystem's MTI logic. During a 600-second test, the detection performance and system power consumption of the four groups were recorded. For comparison, the average power consumption of control group A (full power scan) was set to 100% as the baseline. The test results for each group are shown in Table 1.

[0035] Table 1: Comparison of performance and power consumption under different operating modes.

[0036]

[0037] The analysis of the experimental data is shown in Table 1. Control group A was able to detect the target, but its average power consumption was the highest, at 100%. Control group B had low power consumption (5%), but its floodlight reception method lacked spatial resolution and clutter suppression capabilities; the 15dB target signal was overwhelmed by 40dB clutter, resulting in target loss. Although control group C used asymmetric narrow-beam reception with high spatial resolution, its simple energy detection logic could not distinguish between stationary clutter and moving targets, leading to its failure to detect the target. The narrow beam receiving in the azimuth direction is continuously triggered by 40dB of clutter, activating the wake-up subsystem at high frequency (>1000 times), causing its average power consumption to surge to 95%. Simultaneously, the target signal is also interfered with by clutter, failing to achieve stable detection. The sentinel subsystem of this invention's sample provides high spatial resolution through its asymmetric transmit / receive mechanism, while its built-in lightweight moving target indication (MTI) logic, in coherent processing (e.g., ), making The output energy of the azimuth clutter channel approaches zero (is suppressed), while The output energy of the azimuth moving target channel was retained and exceeded the energy detection threshold; this enabled the sentinel subsystem of the present invention to be untriggered by strong clutter during the entire 600-second test, and was only triggered by the moving target once at t=300 seconds to wake up the subsystem; the test results show that the present invention can detect low signal-to-noise ratio moving targets (SNR=15dB) in a strong clutter background (CNR=40dB), while its relative average power consumption is only 5.2%.

[0038] To further verify the key role of the lightweight moving target indication (MTI) logic (rather than simple energy detection) in solving the technical problems in the background art, the following comparative example 1 is set up.

[0039] Comparative Example 1: This comparative example uses a system configuration that is basically the same as that of Example 1, namely, a radar prototype containing 1000 aperture T / R modules. Through a system controller, 90% of its aperture T / R modules (900 modules) are logically configured as a sentinel subsystem, and 10% of its aperture T / R modules (100 modules) are configured as a wake-up subsystem. The key difference from the present invention is that the operating procedure of the sentinel subsystem in this comparative example is modified: although the sentinel subsystem still adopts a transmit-receive asymmetric mechanism, that is, instructing the 900 T / R modules to perform floodlight transmission at 5% low power and perform digital beamforming during reception. N narrow beam clusters are generated in parallel; however, their signal processors are instructed not to execute the lightweight moving target indication (MTI) logic of this invention, but instead degenerate into an energy detection logic that only performs energy detection on the raw received echoes of the N narrow beam cluster channels; once the energy of any channel exceeds a preset energy detection threshold (which cannot distinguish whether the echo is from stationary clutter or a moving target), the system determines that a potential target has been detected and immediately triggers the activation wake-up subsystem; this configured system is placed in a controlled test in a simulated strong clutter environment, consistent with the environment used in Example 2: through a clutter generator in the monitored airspace A strong stationary clutter signal with a signal-to-noise ratio (CNR) of 40 dB is injected in the azimuth (to simulate strong echo sources such as mountains or large buildings in Example 1); simultaneously, at t=300 seconds, the target simulator is used to monitor the + A moving target signal with a signal-to-noise ratio (SNR) of 15dB was injected into the azimuth, and the total monitoring time of the experiment was set to 600 seconds.

[0040] During the 600-second test, the operating status and detection performance of the comparative system were recorded. The results are as follows: At the start of the test (t=0 seconds), the sentinel subsystem immediately detected a 40dB strong energy echo in the narrow beam receiving channel at 0° azimuth (corresponding to a strong static clutter source). Since the sentinel subsystem only executes energy detection logic, this 40dB clutter energy far exceeds the preset energy detection threshold, causing the system to immediately determine that a potential target has been detected and activate the wake-up subsystem (10% aperture, 100% peak power) to detect the target. Azimuth is confirmed using a pencil beam; because the stationary clutter signal is continuously injected, the energy detection logic of the sentinel subsystem is affected. The azimuth was continuously triggered by clutter. System logs show that during the 600-second test, the wake-up subsystem was activated frequently (over 1000 activation events were recorded), and the wake-up subsystem was almost in a long-term running state; at t=300 seconds, it was located at + A 15dB moving target signal appears in the azimuth direction. Although its 15dB energy may exceed the energy detection threshold, the system is always in a state of being detected. In a state of continuous busy confirmation caused by high-frequency triggering of strong clutter at 40dB azimuth, system resources are occupied by false alarms for an extended period, resulting in... The signals of real moving targets appearing in the azimuth were submerged, failing to achieve stable detection. Calculations showed that, under this comparative operating mode, the relative average power consumption of the wake-up subsystem surged to approximately 95% due to high-frequency activation by clutter (this value is based on the power consumption of the traditional narrow-beam full-power scanning method as 100%). Experimental results indicate that if only the asymmetric transmit / receive (floodlight transmission + narrow-beam reception) technical path is adopted, without the crucial lightweight moving target indication (MTI) logic processing stage of this invention, although the system possesses high spatial resolution, its energy detection logic cannot distinguish between stationary clutter and moving targets. In a strong clutter background, this will lead to a surge in false alarm rates, frequently activating the high-power wake-up subsystem, causing its average power consumption to degrade to almost the same level as the traditional full-power scanning (95% vs 100%), and failing to effectively detect moving targets, thus failing to solve the technical problems existing in the background technology.

[0041] Example 3: This example combines Figures 1 to 3 This describes a low-power, high-power-density active phased array radar system, such as... Figure 1 As shown, the system controller executes dynamic logic partitioning and control procedures, logically dividing the aperture T / R component physical resource pool into a sentinel subsystem and a wake-up subsystem. The sentinel subsystem performs floodlight transmission for low-power illumination in the wide-area surveillance airspace, then forms N receiving narrow beam clusters in parallel through digital beamforming (DBF), and uses lightweight moving target indication (MTI) logic to process coherent pulse train echoes to suppress clutter. Subsequently, it detects the energy of moving targets through wide-area presence detection logic. The threshold of this detection logic is dynamically adjusted by a background processing unit, which performs non-linear processing based on the received data. Coherent long-time integration is used to generate a static clutter background map. When a target is detected, the sentinel subsystem outputs high-precision azimuth information to trigger activation, thereby activating the wake-up subsystem to operate at high power density and instructing it to perform high-power pencil beam confirmation. This confirmation is only directed to the high-precision azimuth to avoid secondary searches and outputs refined target parameters. At the same time, the low-precision observation parameters provided by the sentinel subsystem and the high-precision measurement parameters provided by the wake-up subsystem are sent to the long-time statistical analysis closed-loop self-calibration logic unit. This unit determines systematic drift by analyzing information residuals and outputs calibration beamforming parameters to correct the digital beamforming (DBF) of the sentinel subsystem.

[0042] like Figure 2As shown in the chart, this graph illustrates different resource levels, from level 1 to level 5, and reveals the trends of three key parameters as the resource level increases: the minimum identifiable SNR (dB) (represented by the bar chart) decreases with increasing resource level; the T / R component usage percentage (represented by the dashed line and corresponding to the right Y-axis) increases with increasing resource level; and the signal-to-noise ratio margin threshold (dB) (represented by the solid line and corresponding to the left Y-axis) decreases with increasing resource level. This margin threshold is used by the sentinel subsystem to select a matching resource configuration scheme from the library based on the observed signal-to-noise ratio margin when triggering wake-up. Figure 3 As shown, the system controller FPGA / signal processor divides the T / R component logic into a sentinel subsystem and a wake-up subsystem. The sentinel subsystem contains, for example, 70%-95% of the T / R components and operates at low power, for example, 5% peak power. Its signal processing logic performs floodlight transmission for wide-area coverage and, upon reception, performs digital beamforming of N narrow beams, MTI logic three-pulse cancellation, and moving target detection clutter suppression to determine the i-th beam with high-precision azimuth and trigger the wake-up subsystem. The wake-up subsystem contains, for example, 5%-30% of the T / R components and is activated to operate at high power density, for example, 100% peak power. It receives azimuth information transmission, forms a pencil beam for precise aiming, and performs full-function measurement logic pulse compression + Doppler processing to complete the measurement of refined target parameters such as distance, velocity, RCS, and target track establishment.

[0043] Example 4: This example illustrates a calibration procedure for determining key operating parameters and thresholds in the radar system of the present invention, enabling the system to be configured into a reliable and efficient operating state before deployment. The calibration process is conducted in a controlled test environment, using a signal generator, target simulator, and standard noise source to perform excitation and response measurements on the constructed radar prototype system (including the system controller and aperture T / R components). First, the energy detection threshold calibration procedure for the sentinel subsystem is performed. In the initial state definition of this procedure, the target is the sentinel subsystem (configured at 90% aperture, operating in 5% low-power floodlight transmission, digital beamforming parallel narrow beam reception mode, with MTI logic temporarily disabled), and the enabling environment is an injection environment with a known average power level. The test environment for Gaussian white noise signals; the calibration steps are as follows: First, the system controller instructs the sentinel subsystem to run in a pure noise environment and record its... A single receiving narrow beam cluster channel covers a period of time (coverage) The first step involves analyzing the energy values ​​output by each detection unit; the second step involves statistically analyzing the energy values ​​of each channel and calculating its probability density function; the third step involves calculating the false alarm probability based on a preset value. (Set as) The corresponding energy detection threshold is calculated based on a noise statistical model (such as Rayleigh distribution or chi-square distribution). This threshold is then stored in the system controller as the base energy detection threshold for the sentinel subsystem in non-MTI mode; if the measured average power of a certain channel noise is -90dBm and its distribution conforms to a Rayleigh distribution, in order to achieve The calculated energy detection threshold It is set at -76.2dBm.

[0044] Secondly, the output threshold calibration procedure for the lightweight moving target indication (MTI) logic of the sentinel subsystem is performed; the initial state is defined as follows: the target is still the sentinel subsystem (90% aperture, 5% low power), at which point the coherent pulse train transmission and the lightweight moving target indication (MTI) logic are activated (three-pulse cancellation); the enabling environment includes injecting a stationary clutter signal with a known CNR (CNR=40dB). (Direction) and moving target signal with known SNR (SNR=15dB to +15) (Azimuth, with a specific Doppler frequency shift); Calibration steps: First, the system controller instructs the sentinel subsystem to operate in this mixed signal environment and record all... The output signal of each channel after MTI processing The second step is to calculate the power of the MTI output signal for each channel. The third step is to analyze 0. Statistical distribution of output power in azimuth (clutter) channel and +15 The fourth step is to set an MTI output threshold, representing the output power value of the azimuth (target) channel. The threshold is selected to ensure the output power of the target channel. Greater than The probability of detection () Meets design requirements () ), while also increasing the output power of the clutter channel Greater than The probability (false alarm probability of clutter) ) below an acceptable level ( ); By measurement, if the target channel MTI output power is -80dBm and the statistical mean of the residual power in the clutter channel is -95dBm, then the MTI output threshold is... It can be set to -85dBm; Threshold replacement This serves as the basis for determining the wide-area presence detection operation rules of the sentinel subsystem when MTI logic is enabled; secondly, the confirmation threshold calibration procedure for the wake-up subsystem is performed; initial state definition: the target is the wake-up subsystem (configured at 10% aperture), operating in 100% peak power pencil beam mode, executing full-function measurement logic; the enabling environment is a test environment with only injected target signal, whose parameters (distance, RCS) are set to the weakest target condition that the system needs to reliably confirm; calibration steps: first, the system controller instructs the wake-up subsystem to perform multiple measurements on the weakest target signal; second, record the signal-to-noise ratio (SNR) value obtained from each measurement; third, analyze the statistical distribution (mean) of these SNR values. and standard deviation Step 4: Set the confirmation threshold The threshold is set to ensure that the confirmation probability of the weakest target reaches the required level (99.9%), while considering a certain SNR fluctuation tolerance; one setting method is to... Settings Nearby; if the average SNR for the weakest target is measured to be 13 dB with a standard deviation of 0.5 dB, then the threshold is confirmed. It can be set to 11.5dB; this The threshold is stored in the system controller and used in the signal-to-noise ratio decision-making stage of the hierarchical resource allocation mechanism.

[0045] Finally, the procedure for setting key parameters in the closed-loop self-calibration logic is presented; this procedure is based on prior analysis of the drift characteristics of internal system parameters; the parameter setting steps are as follows: First, set the number of events for long-term statistical analysis. ; The smoothness of the statistical balance of the value and the timeliness of the drift response are determined based on the expected rate of change of the phase stability of the aperture T / R component with temperature and time. If the expected systematic angular drift rate is slow, The first step is to set a wake-up event time of 1000 successful wake-ups; the second step is to set up systemic drift. The threshold for judgment, i.e., the size of the zero window, is set based on the system's tolerance for angle measurement accuracy. For example, if the system requires an angle error of less than 0.1... The threshold used to determine drift can then be set to ± When calculated When the window is exceeded, the system controller triggers a calibration of the sentinel subsystem's received beamforming parameters; these parameters ( The zero-window threshold is set during system initialization. By executing the above series of calibration procedures, the key operating thresholds and parameters of the low-power, high-power-density active phased array radar system are determined based on objective measurements and engineering trade-offs, reducing uncertainties in the implementation process and enabling the system to stably and reliably execute its sentinel wake-up asynchronous operation logic in actual deployment as designed.

[0046] Example 5: To determine the operating parameters of the proportional wake-up resource allocation mechanism under different target characteristics and environments, it is necessary to pre-construct a preset resource level library and its mapping relationship with the signal-to-noise ratio margin. This construction process follows an offline calibration procedure. This procedure is executed in a simulation environment or controlled field test. The initial state is defined as follows: the target is the wake-up subsystem (configured with a specific proportional aperture, such as 10% T / R components), and the environment is enabled to generate standard target signals with different radar cross sections, different distances, and different velocities. The calibration steps are as follows: First, define a set of discrete wake-up resource configuration schemes. Each scheme represents a resource level, specifically defining the number of T / R components called, the percentage of transmit power, and the length of coherent accumulation time. In the example, level 1 (lowest resource) is configured to call 5% T / R components, 50% power, and the shortest pulse train. Level N (highest resource) is configured to call all T / R components (10%) of the wake-up subsystem, 100% power, and the longest pulse train. Second, for each resource level configuration, through simulation or actual measurement, determine whether it can achieve a preset confirmation probability (set) The lower limit of the target signal strength for successfully performing refined target parameter measurements, i.e., the minimum verifiable signal-to-noise ratio corresponding to this level. The third step, based on the results of the second step, is to reverse-engineer the different... The required signal-to-noise ratio margin range for the corresponding sentinel subsystem; in specific calculations, if level k can be confirmed... The target of dB, and the detection threshold of the sentinel subsystem corresponding to dB, then the signal-to-noise ratio margin It must be greater than or equal to 2dB; by repeating this process for all resource levels, a mapping table is established between the signal-to-noise ratio margin range observed by the sentinel subsystem and the wake-up resource level configuration scheme to be invoked. This table is then embedded in the system controller and used to query and select the appropriate resource configuration scheme based on the signal-to-noise ratio margin calculated by the sentinel subsystem during online operation.

[0047] To ensure the sentinel subsystem's autonomous avoidance capability in interference-prone environments and the pointing accuracy of its digital beamforming, a pre-calibration and parameter generation procedure is performed before deployment or during periodic maintenance. For interference suppression, it is necessary to acquire the array manifold vector or calibrated channel response data required for calculating the receive null weights. This process is completed in a microwave anechoic chamber or open field using a standard signal source. The steps include: first, illuminating the array at different angles using a signal source with known azimuth; second, recording the response amplitude and phase of each T / R component channel of the sentinel subsystem to this signal source; third, constructing the array's response model, i.e., the array manifold, based on these response data. When running online, the interference covariance analysis logic unit estimates the direction of incoming interference. Subsequently, the system controller uses pre-stored array manifold data to calculate a specific set of receiving beamforming weights through an adaptive beamforming algorithm. One specific algorithm involves solving a constrained optimization problem. Under the constraint of zero directional response, maximize the desired signal direction or minimize the noise output; for the sentinel subsystem. The pointing accuracy of each receiving narrow beam cluster is also calibrated using a standard signal source with a known direction. By adjusting the complex weighting coefficients used in the DBFN operation, the actual maximum response direction of each receiving narrow beam cluster is made consistent with its preset pointing direction. The calibrated complex weighting coefficients are stored in the system controller.

[0048] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A low-power, high-power-density active phased array radar system, characterized in that, include: The phased array radar consists of aperture T / R modules and a system controller. The system controller is configured to: dynamically divide the aperture T / R modules into a sentinel subsystem and a wake-up subsystem; instruct the sentinel subsystem to perform a floodlight transmission operation to illuminate a wide-area surveillance airspace; and in the receiving time slot immediately following the floodlight transmission, instruct the signal processor of the sentinel subsystem to perform digital beamforming operations on the received data from the aperture T / R modules to form N receiving narrow beam clusters in parallel within the wide-area surveillance airspace. The system controller is also configured to: instruct the sentinel subsystem to transmit a set of coherent pulse trains; and the signal processor of the sentinel subsystem employs a lightweight moving target indication (MTI) logic to coherently process the echoes of the coherent pulse trains on the N receiving narrow beam cluster channels. The wide-area presence detection operation rules of the sentinel subsystem are set as follows: only if the presence detection occurs on the 1st day after the lightweight moving target indication (MTI) logic processing. When the receiving narrow beam channel detects energy indicated as a moving target, it is determined that a potential target has been detected, and the first narrow beam channel... The preset direction of a receiving narrow beam channel is determined as the high-precision azimuth information of a potential target; Furthermore, in response to wide-area presence detection, the wake-up subsystem is activated to operate at high power density and instructed to form a pencil beam, with the direction of the pencil beam only set to be from the first... High-precision azimuth information determined by a narrow beam channel.

2. The low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The system controller is configured such that: when the signal processor of the command sentry subsystem uses the lightweight moving target indication (MTI) logic, it only performs double-pulse cancellation and triple-pulse cancellation operations; and it commands the signal processor of the wake-up subsystem to execute the full-function measurement logic consisting of pulse compression and Doppler processing.

3. The low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The system controller is also configured to: send the received data of the sentinel subsystem in parallel to an interference covariance analysis logic unit during the operation of the sentinel subsystem; the interference covariance analysis logic unit is configured to: analyze the spatial correlation of the received data and determine whether there is an interference source and its direction of arrival; and when the interference source and its direction of arrival are determined, the system controller is configured to: calculate a set of receiving beamforming weights that form a receiving null in the direction of arrival of the interference source, and apply the receiving beamforming weights to the sentinel subsystem.

4. The low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The sentinel subsystem comprises 70% to 95% of the aperture T / R components, while the wake-up subsystem comprises 5% to 30% of the aperture T / R components; the sentinel subsystem and the wake-up subsystem operate asynchronously in timing.

5. The low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The system controller is also configured to: set an energy detection threshold for the wide-area presence detection operation rules of the sentinel subsystem; send the received data to a background processing unit in parallel; the background processing unit is configured to: perform incoherent long-time integration on the subthreshold signals in the received data that are below the energy detection threshold, and generate a static clutter background map; and the energy detection threshold is configured to be spatially adjusted according to the static clutter background map.

6. The low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The system controller is also configured to: after the wake-up subsystem performs target parameter measurement on the high-precision azimuth information, determine the signal-to-noise ratio of the measurement; and when the determination is that the signal-to-noise ratio is lower than a preset confirmation threshold, the system controller is configured to immediately instruct the sentinel subsystem and the aperture T / R component of the wake-up subsystem to perform logical merging, and perform an upgrade confirmation on the high-precision azimuth information with the full aperture and peak power density of the phased array radar.

7. The low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The system controller is also configured to: after the wake-up subsystem confirms a potential target and establishes a target track; transfer the target track tracking task to a tracking subsystem dynamically composed of aperture T / R components; and enable the sentinel subsystem and the wake-up subsystem to resume their wide-area presence detection and on-demand activation operating logic.

8. A low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The sentinel subsystem is also configured to calculate the signal-to-noise ratio margin of potential targets in wide-area presence detection; and the system controller is configured to select a resource configuration scheme from a preset resource level library based on the signal-to-noise ratio margin; and instruct the wake-up subsystem to use a predetermined power aperture resource when using pencil beams, according to the resource configuration scheme.

9. A low-power, high-power-density active phased array radar system according to claim 1, characterized in that, The system controller is also configured to: after the wake-up subsystem successfully confirms the potential target, acquire the high-precision measurement parameters measured by the wake-up subsystem, and the low-precision observation parameters observed by the sentinel subsystem at the time of triggering; Based on the information residuals between high-precision measurement parameters and low-precision observation parameters, long-term statistical analysis is performed to determine whether there is systematic drift in the operating parameters of the sentinel subsystem. By analyzing information residuals Perform long-term integral statistics To determine, For the first Secondary information residual, The number of events for statistical analysis; Based on the results of the systematic drift assessment, the detection threshold and beamforming parameters of the sentinel subsystem are calibrated.

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