Transmit phased array self-excitation positioning and elimination method

Abstract

The application provides a transmitting phased array self-excitation positioning and eliminating method, and relates to the field of phased array detection. The method combines and outputs each antenna subarray of an antenna array to a first port of a test instrument through a first combining network, and combines and outputs each power amplification component to a second port of the test instrument through a second combining network; the physical distance between the antenna array and the power amplification component is set, the gain singular point is extracted by acquiring a transmission characteristic curve; if the singular point exists, the self-excitation judgment value is calculated based on the test gain at the singular point, the space loss and the preset allowance; if the judgment value meets the preset condition, the low-frequency and radio frequency signal leakage points in the system are sequentially investigated and shielded; finally, the components in the latter stage circuit are sequentially connected for step-by-step verification. The application avoids repeated blind disassembly of the whole machine, does not need to rely on a special microwave darkroom, and significantly improves the safety, output efficiency and flexibility of debugging and troubleshooting.

Description

Technical Field

[0001] This invention relates to the field of phased array detection technology, and more specifically, to a method for self-excitation localization and elimination of a transmitting phased array. Background Technology

[0002] Currently, multi-element transceiver systems, represented by active phased arrays, are widely used in numerous fields. With the further development of electronic technology, the requirements for system size, weight, and dimensions on various platforms are becoming increasingly stringent. This inevitably promotes the continuous improvement of the integration of active phased arrays, resulting in increasingly dense arrangement of internal components and wiring. Simultaneously, to achieve superior system performance, transmitting phased arrays are also developing towards higher power and higher efficiency. Under this trend of high integration and high power, the radio frequency (RF) or low-frequency signals after inter-stage interconnection are highly susceptible to leakage through spatial coupling or gaps. When the leaked signal is received and amplified again by the front-end circuit, forming a positive feedback loop, it can trigger severe RF self-oscillation. Electromagnetic compatibility and RF self-oscillation issues not only lead to system waveform distortion and component burnout, but their impact on the final performance of the entire system is also becoming increasingly serious, becoming a major pain point restricting the development of high-power phased array systems.

[0003] Because high-power microwave radiation poses a significant health risk, the industry strictly prohibits the direct power-on debugging and testing of high-power phased array transmitters in open-plan office environments to ensure the safety of testing personnel. Typical phased array systems are extremely complex, usually consisting of multiple layers of components, including antenna arrays, transceiver (TR) components, multi-layered RF routing, power supply components, and control circuits. Traditional troubleshooting procedures often require a lengthy and complex assembly and sealing process before the entire system can be moved to a dedicated microwave anechoic chamber for overall performance testing. Microwave anechoic chambers are expensive and scarce testing resources. If a self-oscillation problem only emerges during the overall system testing phase, testing personnel will face significant troubleshooting difficulties. Since the system is already assembled and its internal working state is invisible, engineers need to spend considerable time troubleshooting and identifying the source of the self-oscillation, which not only wastes valuable anechoic chamber resources but also severely reduces testing efficiency.

[0004] Even more challenging is that traditional troubleshooting methods struggle to systematically and accurately isolate and pinpoint potential low-frequency and RF self-oscillation sources in antennas, power amplifiers, driver layers, and routing layers. In extreme cases, due to the difficulty in accurately locating specific connector gaps or housing leaks in a single operation, repeated blind disassembly and reassembly of the extremely complex device are often required. This not only easily causes secondary physical damage to delicate RF components and structural parts but also significantly extends the product development and production cycle. Therefore, finding a highly versatile, adaptable, and simple method for locating and eliminating self-oscillations in transmit phased arrays, while ensuring the safety of test personnel from electromagnetic radiation and reducing reliance on dedicated large-scale testing environments such as microwave anechoic chambers, to avoid repeated disassembly and reassembly and improve test output efficiency, has become a pressing technical challenge for those skilled in the art. Summary of the Invention

[0005] The present invention aims to solve at least one of the aforementioned technical problems existing in the prior art.

[0006] Therefore, the present invention provides a method for self-excited positioning and elimination of a phased array.

[0007] This invention provides a method for self-excitation localization and elimination of a phased array transmitter, comprising: Each antenna subarray of the antenna array is combined and output to the first port of the test instrument via a first combining network, and each power amplifier component is combined and output to the second port of the test instrument via a second combining network. Set the physical distance between the antenna array and the power amplifier component, control the power amplifier component to be in an unexcited transmission state, and obtain the transmission characteristic curve through the test instrument to extract the gain singularity. If the gain singularity exists, then the self-oscillation judgment value is calculated based on the test gain at the singularity, the spatial loss determined by the physical distance and the test frequency, and the preset margin. If the self-excitation determination value meets the preset conditions, then the low-frequency signal leakage points and radio frequency signal leakage points in the system are investigated in sequence, and shielding materials are used for shielding treatment until the self-excitation determination value corresponding to the affected gain singularity point no longer meets the preset conditions. After eliminating the self-oscillation of the previous stage circuit, the subsequent stage circuit components are connected in sequence and the RF load is changed to perform self-oscillation troubleshooting of the subsequent stage circuit components until the self-oscillation troubleshooting of all subsequent stage circuit layers is completed.

[0008] The self-excited positioning and elimination method for the transmitting phased array according to the above technical solution of the present invention may also have the following additional technical features: In the above technical solution, before the antenna subarrays of the antenna array are combined and output through the first combining network, the method further includes: individually testing each active functional unit of the phased array to confirm whether there is self-oscillation; if self-oscillation occurs in a single stage, the state of the link gain adjustment circuit is adjusted and fixed to eliminate single-stage self-oscillation.

[0009] In the above technical solution, the antenna array is divided into m row or column antenna subarrays, and each subarray includes n element antennas; the first combining network includes m first radio frequency n combiners and one first radio frequency m combiner; the second combining network includes m second radio frequency n combiners and one second radio frequency m combiner; where n is a positive integer greater than or equal to 1, and m is a positive integer greater than or equal to 2.

[0010] In the above technical solution, the step of combining and outputting the individual antenna subarrays of the antenna array to the first port of the test instrument via a first combining network includes: Each antenna subarray is connected to the corresponding first RF n combiner, and the n unit antennas are combined. The output signals of the m first RF n combiners are then combined into one channel by the first RF m combiner and connected to the transmit port of the vector network analyzer; The step of combining and outputting the various power amplification components via a second combiner network to the second port of the test instrument includes: Each power amplifier component is connected to the corresponding second RF n combiner to combine the n RF signals; The output signals of the m second RF n combiners are then combined into one channel by the second RF m combiner and connected to the receiving port of the vector network analyzer.

[0011] In the above technical solution, before the steps of combining and outputting the individual antenna subarrays of the antenna array through the first combining network to the first port of the test instrument, and combining and outputting the individual power amplification components through the second combining network to the second port of the test instrument, a gain normalization step is further included: Connect the corresponding ports of each first RF n-combiner to the second RF n-combiner; The common terminals of the first RF m combiner, which combines each of the first RF n combiners, and the second RF m combiner, which combines the second RF n combiners, are respectively connected to the test instrument. The gain of the test instrument is normalized in the required test frequency band; After gain normalization is completed, disconnect the connection between the first RF n-combiner and the second RF n-combiner.

[0012] In the above technical solution, the method for calculating the self-excitation determination value is as follows:

[0013] Where S represents the self-excitation determination value; L represents the test gain at the singular point; I represents the space loss; and I represents the preset margin, which ranges from 3 to 5. The method for calculating the space loss is as follows:

[0014] Where d represents the physical distance between the antenna array and the power amplifier components; f represents the frequency.

[0015] In the above technical solution, the self-excitation determination value satisfying the preset condition means that the self-excitation determination value is greater than 0, and the self-excitation determination value no longer satisfying the preset condition means that the self-excitation determination value is not greater than 0.

[0016] In the above technical solution, the step of investigating low-frequency signal leakage points in the system and using shielding materials for shielding treatment includes: Wrap the low-frequency signal connector with conductive cloth for shielding and observe whether the transmission characteristic curve shows any self-excitation point following the change. If the affected self-excitation determination value still meets the preset condition, the number of wrapping layers is increased until the self-excitation determination value no longer meets the preset condition.

[0017] In the above technical solution, the step of investigating radio frequency signal leakage points in the system and using shielding materials for shielding treatment includes: The potential leakage points are tentatively blocked or shielded using flat plate absorbing material, and the changes in the transmission characteristic curve are observed to find the location of the radio frequency signal leakage point. After locating the leak, cover the self-excited area of ​​the RF circuit with absorbing material, or cover the outside of the leakage point with shielding metal foil tape. If the affected self-excitation determination value still meets the preset conditions, the number of pasting layers is increased until the self-excitation determination value no longer meets the preset conditions.

[0018] In the above technical solution, the downstream circuit components include an RF driver component and an RF router; the RF driver component is divided into k layers according to the actual physical layout for step-by-step investigation and processing, where k is a positive integer greater than or equal to 1; the RF router is divided into j layers according to the actual physical layout for step-by-step investigation and processing, where j is a positive integer greater than or equal to 1.

[0019] In summary, due to the adoption of the above-mentioned technical features, the beneficial effects of the present invention are: First, the innovative phased array self-oscillation troubleshooting method of this invention can be effectively applied to engineering practice, avoiding personal injury to test personnel caused by high-power self-oscillation during R&D and production, while also preventing radiation pollution to the environment. Second, the streamlined method of this invention ensures that engineers can complete the location and troubleshooting of self-oscillation by following a predetermined procedure, without repeatedly disassembling and reassembling the entire device. This approach allows test personnel to complete phased array debugging in one go, greatly saving troubleshooting time and effectively shortening the product development cycle.

[0020] Furthermore, the method proposed in this invention can adapt to any environment. Unlike traditional high-power transmission testing, which requires a microwave anechoic chamber, this method does not require a dedicated testing location, thus greatly improving the efficiency and flexibility of debugging and testing. Regarding testing costs, the requirements for this invention are simple, requiring only a vector network analyzer and an RF power divider or combiner. Since the testing components are not consumable and can be reused multiple times, this is a method with low implementation difficulty and extremely low application cost.

[0021] Meanwhile, the solution of this invention can accurately locate and eliminate various potential sources of self-oscillation, such as circuit levels, connectors, and structural components, achieving comprehensive investigation and handling of high-power transmission self-oscillation. Finally, the method proposed in this invention has excellent versatility and is well applicable to various phased array systems with different architectures and forms.

[0022] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0023] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the principle topology of a self-excited localization and elimination method for a phased array transmitter proposed in this invention. Figure 2 This is a flowchart of a self-excited localization and elimination method for a phased array transmitter proposed in this invention. Detailed Implementation

[0024] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0026] The following reference Figure 1 and Figure 2 This describes a method for self-excitation localization and elimination of a phased array transmission according to some embodiments of the present invention.

[0027] Some embodiments of this application provide a method for self-excitation localization and elimination of a phased array.

[0028] The first embodiment of this invention proposes a method for locating and eliminating self-oscillation in a transmitting phased array. Typically, self-oscillation occurs due to spatial coupling leakage of radio frequency or low-frequency signals after inter-stage interconnection, which is then received by the front-end circuit, forming a positive feedback loop. To address this problem at its root, this method utilizes a reasonable process and an external testing network to achieve comprehensive safety checks from both low-frequency and radio frequency dimensions.

[0029] Specifically, the following steps are included: Each antenna subarray of the antenna array is combined and output to the first port of the test instrument via a first combining network, and each power amplifier component is combined and output to the second port of the test instrument via a second combining network. Set the physical distance between the antenna array and the power amplifier component, control the power amplifier component to be in an unexcited transmission state, and obtain the transmission characteristic curve through the test instrument to extract the gain singularity. If the gain singularity exists, then the self-oscillation judgment value is calculated based on the test gain at the singularity, the spatial loss determined by the physical distance and the test frequency, and the preset margin. If the self-excitation determination value meets the preset conditions, then the low-frequency signal leakage points and radio frequency signal leakage points in the system are investigated in sequence, and shielding materials are used for shielding treatment until the self-excitation determination value corresponding to the affected gain singularity point no longer meets the preset conditions. After eliminating the self-oscillation of the previous stage circuit, the subsequent stage circuit components are connected in sequence and the RF load is changed to perform self-oscillation troubleshooting of the subsequent stage circuit components until the self-oscillation troubleshooting of all subsequent stage circuit layers is completed.

[0030] Figure 1The diagram illustrates the principle topology of this method. In some embodiments, the entire system under test and test network are mainly divided into an antenna array, a testing and configuration layer, a power layer, a driver layer, a routing layer, and power supply and control components responsible for power supply and logic management. The antenna array typically includes multiple antenna elements. Classified by column or row, the entire actual antenna array can be divided into m row or column antenna subarrays, each subarray containing n antenna elements. Here, to meet the basic requirements of the array, n is defined as a positive integer greater than or equal to 1, and m is defined as a positive integer greater than or equal to 2. To construct the test loop without fully assembling the entire device, a first combining network and a second combining network are innovatively introduced in the testing and configuration layer. The first combining network includes m first RF n combiners and one first RF m combiner (i.e.,... Figure 1 The RF m combiner 1 shown is an example. The second combining network includes m second RF n combiners and one second RF m combiner (i.e., Figure 1 The RF m-combiner shown is 2). The power layer at the back end contains power amplification components, which often include an n-channel final-stage high-power amplifier and matching RF connectors. It is mainly responsible for amplifying the RF signals output by the RF drive components and then outputting them to the aforementioned antenna array for transmission into external space.

[0031] Combination Figure 2 The flowchart shown illustrates in detail the troubleshooting and elimination steps in some embodiments of the present invention. The first step in the troubleshooting is to perform static and dynamic tests on each active functional unit individually to confirm whether self-oscillation occurs in the single-stage state. Normally, self-oscillation does not occur when the component is in a single-stage state. However, if self-oscillation occurs in a single-stage state due to an unreasonable internal link gain design, the tester can adjust and solidify the state of the link gain adjustment circuit to eliminate single-stage self-oscillation at its source before proceeding to the next step, system-level verification. After confirming that the single-stage is normal, the system gain normalization step is formally initiated. The tester needs to physically connect the corresponding ports of each first RF n-combiner and second RF n-combiner strictly according to the channel sequence. Subsequently, the vector network analyzer is set to the required test frequency band. The transmit port of the vector network analyzer is connected to the common terminal of the first RF m-combiner that combines the first RF n-combiners, and the receive port of the vector network analyzer is connected to the common terminal of the second RF m-combiner that combines the second RF n-combiners. After the overall loop connection is completed, the vector network analyzer is subjected to gain normalization within the required test frequency band. The main purpose is to eliminate the insertion loss introduced by the fitting fixtures, combiners, and cables themselves, and to establish an accurate zero-point reference. After completing the strict gain normalization, the direct connection between each of the first RF n-combiners and the second RF n-combiner must be disconnected to prepare for physical isolation when connecting the actual RF components under test.

[0032] In some embodiments, after instrument normalization, the individual antenna subarrays of the actual antenna array need to be combined and output to the first port of the test instrument via a first combining network. Specifically, each antenna subarray is accurately connected to its corresponding first RF n combiner via a standard RF cable, completing the local combining of the n antenna elements. Then, the first RF m combiner of the main circuit combines the output signals of the m antenna subarrays into one and finally connects to the transmit port of the vector network analyzer. Based on the same topology principle, the individual power amplifier components are combined and output to the second port of the test instrument via a second combining network. Specifically, each power amplifier component is connected to its corresponding second RF n combiner via an RF cable, performing energy combining of the n RF signals. Then, the second RF m combiner combines the output signals of the m power amplifier components into one and feeds them back to the receive port of the vector network analyzer. After the entire test loop is constructed, the maximum straight-line physical distance between the antenna array and the power amplifier components in the current placement state is accurately measured and recorded; this physical distance is denoted as d. Next, the actual power supply and control components of the phased array are connected, and the RF input terminals of all power amplifier components are connected to standard RF loads. The phased array system is powered on normally and the logic control of the simulated working state is performed. By applying specific commands, the power amplifier components are forced to be in a pure transmission state without excitation in order to observe their static noise floor and spatial coupling characteristics.

[0033] In some embodiments, while maintaining the above-described device configuration and operating state, the transmission characteristic curve on the vector network analyzer screen, i.e., the S21 curve, is tested and recorded. Engineers need to carefully observe whether there are any peak-shaped gain singularities within the frequency band. If no gain singularities exist across the entire frequency band, it indicates good spatial isolation between the antenna array and the power amplifier components, with no risk of self-oscillation, allowing for direct connection and testing of deeper circuit levels. If a singularity is clearly present on the curve, a self-oscillation judgment value needs to be scientifically calculated based on the test gain at the singularity, the physical distance obtained from the aforementioned measurements, the spatial path loss determined by the test frequency, and the system's preset empirical margin. This self-oscillation judgment value quantifies the self-oscillation risk level and is denoted as S. Its calculation formula is:

[0034] Where S represents the self-excitation determination value; L represents the test gain at the singular point directly read by the cursor of the vector network analyzer; L represents the space loss calculated by the free space propagation theory formula; I represents the preset margin, which is 3-5 to ensure the rigor of the judgment. The method for calculating the space loss is as follows:

[0035] Where d represents the physical distance between the antenna array and the power amplifier component; f represents the specific test frequency corresponding to the singularity extracted by the vector network analyzer, and its unit is set to MHz.

[0036] In some embodiments, after obtaining the exact self-excitation judgment value S through mathematical calculation, it is necessary to further determine whether the calculated value meets the preset conditions for triggering an alarm. The preset conditions specifically refer to the judgment value S being greater than 0.

[0037] If the calculated S is not greater than 0, it indicates that although there are singularities in the spatial fluctuations, their coupling energy has been significantly attenuated by spatial losses, and is insufficient to form a positive feedback loop that could cause destructive self-oscillation under the tiny spacing of the actual phased array assembly. At this point, it can be safely determined that there is no substantial self-oscillation between the antenna array and the power amplifier components, and the investigation of the next stage circuit can proceed smoothly.

[0038] If the calculated judgment value S is greater than 0, it indicates that the system has formed a substantial closed-loop self-oscillation due to strong signal spatial leakage coupling. Hidden self-oscillation leakage points must be located and addressed sequentially according to procedures. The investigation process is systematically divided into two dimensions: low-frequency band and radio frequency band. The investigation team first focuses on low-frequency signal leakage points. Testers use conductive cloth with electromagnetic shielding properties to physically wrap and shield the low-frequency signal connectors within the system. Simultaneously, they must observe in real time whether the transmission characteristic curve of the vector network analyzer shows a corresponding decrease or disappearance of the self-oscillation point. If the gain value corresponding to the affected self-oscillation point changes with the shielding action, the S value after shielding is recalculated to see if it meets the safety threshold of less than or equal to 0. If the safety threshold is not met, i.e., the judgment value S after shielding is still greater than 0, the number of conductive cloth wrapping layers needs to be gradually increased, denoted as the number of wrapping layers p, where p is greater than or equal to 1, until the judgment value S corresponding to the low-frequency self-oscillation point is no greater than 0, thereby completely cutting off the low-frequency leakage path on the physical link.

[0039] After effectively eliminating potential low-frequency leakage, if other singular points on the curve still satisfy the criterion value S greater than 0, a deeper investigation of RF signal leakage points begins. Testers select planar absorbing materials suitable for the current test frequency band to tentatively shield or cover potential high-frequency leakage points such as exposed RF circuit boards, mating RF connectors, mechanical gaps in metal cascade components, and outer casings. By continuously observing the changes in the transmission characteristic curve on the vector network analyzer with the detection position and distance of the absorbing material, the physical location of the RF signal spatial leakage point can be accurately identified, much like radar. After successfully locating the RF self-excitation point, engineers use absorbing materials to permanently or semi-permanently cover the identified RF circuit self-excitation area, or use highly conductive shielding metal foil tape to tightly shield the mechanical leakage point, and then observe again whether the self-excitation point on the instrument screen has significantly decreased. At this point, the aforementioned formula is used again to calculate whether the self-excitation criterion value S after shielding the point is less than or equal to 0. If the conditions are not met, the number of layers of adhesive tape or covering material is gradually increased, denoted as layer number q, where q is greater than or equal to 1, until the self-oscillation judgment value corresponding to the affected high-frequency gain singularity no longer meets the preset condition of being greater than 0, thus completing the self-oscillation elimination task for all frequency bands within the current level.

[0040] In some embodiments, after thoroughly investigating the first-level antenna array and power amplifier components, it is necessary to continue with step-by-step security verification of subsequent circuit layers deeper into the system. After the self-oscillation of the previous stage circuit is confirmed to be eliminated, the tester connects the next stage circuit at the front end and removes the RF load that was originally safely connected to the input of the power amplifier component, and instead connects it to the input of the newly connected next stage circuit. After the load migration is completed, the aforementioned cyclic steps of obtaining the transmission characteristic curve, extracting abnormal singularities, calculating the self-oscillation judgment value, and classifying and eliminating them are repeated. In complex phased array systems, the subsequent circuit components often include RF driver components and RF routing networks. RF driver components generally include a large number of multi-channel RF channels, RF power amplifiers for signal preprocessing, high-precision digitally controlled attenuators, and delay-phase-shifting multifunctional devices for beamforming, etc. According to the actual internal physical three-dimensional layout, they can be divided into k layers for step-by-step investigation and processing, where k is a positive integer greater than or equal to 1. The RF routing network typically includes complex multi-channel RF switches and RF combiners for signal distribution. Based on its actual physical layout within the system, it can also be divided into j layers for progressive isolation verification and troubleshooting, where j is a positive integer greater than or equal to 1. The testing team needs to repeatedly cycle through connecting to subsequent units and testing various indicators until all electrical connections and self-oscillation checks of all subsequent circuit layers are completed. After passing all tests and confirming that there is no risk of self-oscillation positive feedback at any system level, engineers can safely disconnect all temporary test cables between the antenna array and the first matching and combining network, and between the power amplifier components and the second matching and combining network. The final step is to physically assemble and securely connect the antenna array to the internal power amplifier components and each control layer, successfully completing the fully enclosed and safe assembly of the entire phased array system.

[0041] In one specific embodiment, the self-oscillation localization and elimination method for transmitting phased arrays proposed in this invention, which has significant engineering value, was practically applied to the debugging and troubleshooting of a specific model of transmitting phased array production line. This specific model of large-scale transmitting phased array is structurally composed of a 2×4 array antenna array, a power amplifier component responsible for transmission, an RF drive component providing signals, an RF router distributing signals, and a power module and controller responsible for the underlying layers. To ensure the reliability of the test benchmark, the test engineer first conducted separate static power-on tests on the three core components—the power amplifier component, the RF drive component, and the RF router—to confirm that no self-oscillation occurred at the individual component level by reading basic data. Subsequently, the test bench setup phase began. In this embodiment, parameter m is fixed at 2, and parameter n is fixed at 4. The test personnel connected the trunk common terminals of the two first RF 4-way combiners to the two branch input terminals of RF 2-way combiner 1, and connected the common terminals of the two second RF 4-way combiners to the two input common terminals of RF 2-way combiner 2. To perform system-level insertion loss normalization, the corresponding output ports of each of the first RF 4-way combiners and the second RF 4-way combiners are connected back-to-back according to the corresponding order of the RF channels. After setting the vector network analyzer to cover the required broadband test frequency band, its core transmit port (PORT1) is connected to the final common terminal of RF 2-way combiner 1, and its receive port (PORT2) is connected to the final common terminal of RF 2-way combiner 2. The instrument's internal calibration program automatically completes the normalization calibration operation for the gain error of the entire tooling system.

[0042] In this specific embodiment, after the instrument indicates calibration is complete, the tester disconnects all temporary connections between the first and second RF four-way combiners to cut off the direct loop. Each actual antenna subarray is connected to the first RF four-way combiner via a low-loss RF cable, completing the primary RF combining of the four column antenna elements under that subarray. RF two-way combiner 1 then combines the combined output signals of these two antenna subarrays into a single main signal and connects it to the receiver of the test instrument. Simultaneously, a symmetrical operation is performed: each actual power amplifier component is connected to its corresponding second RF four-way combiner via a RF cable of the same specification, spatially combining the four generated RF signals. RF two-way combiner 2 then combines the output signals of these two power amplifier components into a single signal and connects it to the transmitter of the test instrument. Physically, the engineer measures and confirms on-site that the actual maximum straight-line physical distance d between the antenna array aperture surface and the power amplifier component surface at the current workstation is 50cm. After successfully completing the wiring for the power module and controller, the input terminal of the power amplifier component, originally connected to the antenna, was connected to a standard RF load with impedance matching. The entire phased array system was then powered on and its operating status was controlled normally. Specific software configuration ensured that the power amplifier component was in a pure transmit state with DC bias but no RF excitation. At this point, high-precision testing with a vector network analyzer was performed, and the current S21 transmission characteristic curve was recorded. Observation of the frequency band data revealed no abnormal gain singularities, indicating that, based on the testing principle, no spatial self-coupling phenomenon occurred at this first level.

[0043] The investigation continued along the system architecture, delving deeper into the circuitry. To ensure safety, the operator disconnected the power supply to the entire test system, removed the previously installed test load from the power amplifier component's input, and reconnected its wiring to the next-level core RF driver component. A matching load of the same specification was then connected to the driver component's input. After the system was safely powered back on, the instrument refreshed the test transmission characteristic curve. At this point, the tester discovered sharp abnormal gain singularities at frequencies f1 and f2 on the S21 curve. The self-oscillation judgment value S was rigorously calculated using the spatial coupling formula provided in this invention. In this embodiment, to ensure an extremely high safety threshold, the preset margin I was set to 4. After substituting the test parameters for the two frequencies into the formula, it was found that the judgment value S calculated at singularity f1... f1 =2, while the decision value S calculated at the singular point f2 is... f2=5. Since both values ​​exceeded the red line greater than the preset condition 0, it clearly indicates that substantial self-excited oscillations occurred in the upstream and downstream loops within the system. The system needs to be shut down to locate and eliminate internal electromagnetic self-excitement leakage points. Regarding the relatively low frequency f1, technicians, based on experience, initially determined that it might be due to coupling interference from low-frequency control cables or power cables. Therefore, a special electromagnetically conductive cloth was used to tightly wrap and shield the low-frequency multi-core signal connector on the drive component module. After the shielding operation was completed, it was observed in real-time that the self-excited point f1 on the transmission characteristic curve on the instrument screen showed a significant decrease in amplitude following the wrapping action. Recalculating the new data revealed that the judgment value S at this point... f1 The gain dropped significantly to -1dB, meeting the safety requirement of no more than 0, indicating that the low-frequency self-excitation path had been successfully identified and eliminated. For the other higher frequency, f2, technicians determined it to be a spatial leakage of high-frequency radio frequency signals. Operators used microwave-specific flat-panel absorbing material to conduct close-range scanning and blocking detection in the physical space surrounding the power amplifier component and the subsequent radio frequency drive component. During the detection, it was found that when the absorbing material was physically close to the mechanical connection gap between the metal housing of the power amplifier component and the metal housing of the radio frequency drive component, the gain peak fluctuation at the self-excitation point f2 on the instrument curve was the most intense and highly correlated. Thus, this probing method accurately pinpointed this tiny gap as the source of the high-frequency radio frequency signal spatial leakage.

[0044] After pinpointing the exact leak point in this embodiment, the structural engineer meticulously applied and shielded the leak point at the connection seam using shielding copper foil tape with excellent conductivity and electromagnetic shielding performance. After applying one layer of single-sided copper foil tape, the amplitude of the self-excitation point f2 on the instrument curve was observed to decrease by only 2dB. However, after recalculating the S value using the formula, it was found that it might still not reach the safety threshold standard of less than or equal to 0. Therefore, the operator increased the physical thickness of the shielding by adding another layer of copper foil tape of the same specification at the original location. The instrument was then retested, and the calculated judgment value S was found to be... f2 The degradation to 0dB was successfully achieved, perfectly meeting the safety preset condition that the judgment value is not greater than 0. This signifies that the extremely hidden RF self-oscillation risk of this array has been completely and safely eliminated. After ensuring the physical and electrical stability of this driver level, in-depth verification was then carried out on the lower-level routing components.

[0045] The main power supply was disconnected again, and the test load at the front-end input of the RF drive component was removed. Its signal path was then changed to connect to the next-level RF routing control module, and the final test load was connected to the bottom-level input of the RF routing module. After ensuring all cables were correct, the system was powered on, and the current global transmission characteristic curve was tested. The results showed that the characteristics were extremely smooth throughout the entire operating frequency band, and no new singularity spikes were found. This fundamentally proved that the multi-stage cascade self-oscillation risk of the entire phased array transmission system had been completely eliminated. After all procedures were completed and the indicators were qualified, all test cables were disconnected from the actual antenna array and the first RF 4-way combiner network of the fixture, and from the power amplifier component and the second RF 4-way combiner network of the fixture. Finally, the antenna array housing and the power amplifier component frame were securely and reliably connected and tightened with screws.

[0046] The aforementioned detailed and specific troubleshooting examples irrefutably demonstrate that the technical solution proposed by this invention can be scientifically, rationally, and feasiblely applied to various practical engineering troubleshooting scenarios of phased array transmission self-excitation. This eliminates the need for engineers to perform traditional, complex assembly of the entire machine and transport it to a microwave anechoic chamber for blind manual disassembly and assembly, thereby significantly improving the safety, troubleshooting convenience, and overall production output efficiency of the modern phased array system R&D and testing process.

[0047] In this specification, the illustrative expressions of the terms used do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0048] Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention shall be included within the scope of protection of this invention.

Claims

1. A method for self-excited positioning and elimination of a transmitting phased array, characterized in that, include: Each antenna subarray of the antenna array is combined and output to the first port of the test instrument via a first combining network, and each power amplifier component is combined and output to the second port of the test instrument via a second combining network. Set the physical distance between the antenna array and the power amplifier component, control the power amplifier component to be in an unexcited transmission state, and obtain the transmission characteristic curve through the test instrument to extract the gain singularity. If the gain singularity exists, then the self-oscillation judgment value is calculated based on the test gain at the singularity, the spatial loss determined by the physical distance and the test frequency, and the preset margin. If the self-excitation determination value meets the preset conditions, then the low-frequency signal leakage points and radio frequency signal leakage points in the system are investigated in sequence, and shielding materials are used for shielding treatment until the self-excitation determination value corresponding to the affected gain singularity point no longer meets the preset conditions. After eliminating the self-oscillation of the previous stage circuit, the subsequent stage circuit components are connected in sequence and the RF load is changed to perform self-oscillation troubleshooting of the subsequent stage circuit components until the self-oscillation troubleshooting of all subsequent stage circuit layers is completed.

2. The method for self-excited positioning and elimination of a phased array transmission according to claim 1, characterized in that, Before the antenna subarrays of the antenna array are combined and output through the first combining network, the method further includes: individually testing each active functional unit of the phased array to confirm whether there is self-oscillation; if self-oscillation occurs in a single stage, the state of the link gain adjustment circuit is adjusted and fixed to eliminate single-stage self-oscillation.

3. The method for self-excited positioning and elimination of a phased array transmission according to claim 2, characterized in that, The antenna array is divided into m row or column antenna subarrays, each subarray including n element antennas; the first combining network includes m first RF n combiners and one first RF m combiner; the second combining network includes m second RF n combiners and one second RF m combiner; where n is a positive integer greater than or equal to 1, and m is a positive integer greater than or equal to 2.

4. The method for self-excited positioning and elimination of a phased array transmission according to claim 3, characterized in that, The step of combining and outputting the individual antenna subarrays of the antenna array to the first port of the test instrument via a first combining network includes: Each antenna subarray is connected to the corresponding first RF n combiner, and the n unit antennas are combined. The output signals of the m first RF n combiners are then combined into one channel by the first RF m combiner and connected to the transmit port of the vector network analyzer; The step of combining and outputting the various power amplification components via a second combiner network to the second port of the test instrument includes: Each power amplifier component is connected to the corresponding second RF n combiner to combine the n RF signals; The output signals of the m second RF n combiners are then combined into one channel by the second RF m combiner and connected to the receiving port of the vector network analyzer.

5. The method for self-excited positioning and elimination of a phased array transmission according to claim 3, characterized in that, Before combining and outputting the individual antenna subarrays of the antenna array to the first port of the test instrument via the first combining network, and combining and outputting the individual power amplifier components to the second port of the test instrument via the second combining network, a gain normalization step is also included: Connect the corresponding ports of each first RF n-combiner to the second RF n-combiner; The common terminals of the first RF m combiner, which combines each of the first RF n combiners, and the second RF m combiner, which combines the second RF n combiners, are respectively connected to the test instrument. The gain of the test instrument is normalized in the required test frequency band; After gain normalization is completed, disconnect the connection between the first RF n-combiner and the second RF n-combiner.

6. The method for self-excited positioning and elimination of a phased array transmission according to claim 1, characterized in that, The method for calculating the self-excitation determination value is as follows: Where S represents the self-excitation determination value; L represents the test gain at the singular point; I represents the space loss; and I represents the preset margin, which ranges from 3 to 5. The method for calculating the space loss is as follows: Where d represents the physical distance between the antenna array and the power amplifier components; f represents the frequency.

7. The method for self-excited positioning and elimination of a phased array transmission according to claim 6, characterized in that, The self-excitation determination value satisfies the preset condition when the self-excitation determination value is greater than 0, and the self-excitation determination value no longer satisfies the preset condition when the self-excitation determination value is not greater than 0.

8. The method for self-excited positioning and elimination of a phased array transmission according to claim 1, characterized in that, The process of identifying and shielding low-frequency signal leakage points in the system includes: Wrap the low-frequency signal connector with conductive cloth for shielding and observe whether the transmission characteristic curve shows any self-excitation point following the change. If the affected self-excitation determination value still meets the preset condition, the number of wrapping layers is increased until the self-excitation determination value no longer meets the preset condition.

9. The method for self-excited positioning and elimination of a phased array transmission according to claim 1, characterized in that, The process of identifying and shielding radio frequency signal leakage points in the system includes: The potential leakage points are tentatively blocked or shielded using flat plate absorbing material, and the changes in the transmission characteristic curve are observed to find the location of the radio frequency signal leakage point. After locating the leak, cover the self-excited area of ​​the RF circuit with absorbing material, or cover the outside of the leakage point with shielding metal foil tape. If the affected self-excitation determination value still meets the preset conditions, the number of pasting layers is increased until the self-excitation determination value no longer meets the preset conditions.

10. The method for self-excited positioning and elimination of a phased array transmission according to claim 1, characterized in that, The subsequent circuit components include an RF driver component and an RF router; the RF driver component is divided into k layers according to the actual physical layout for step-by-step investigation and processing, where k is a positive integer greater than or equal to 1; the RF router is divided into j layers according to the actual physical layout for step-by-step investigation and processing, where j is a positive integer greater than or equal to 1.

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