Self-calibration switch array for direction-finding communication system

Abstract

The invention discloses a self-calibration switch array for a direction-finding communication system, and relates to the technical field of communication processing. Comprising a calibration signal generation module, a switching control module and an antenna signal processing module. The calibration signal generation module uses a 100M constant-temperature crystal oscillator as a reference, generates a calibration signal through a VCO oscillation phase-locked circuit, and enters an antenna path after frequency and amplitude are adjusted; the switching control module adopts an electronic switch to switch a path, and adopts a split-plate and split-cavity design to realize space shielding; the antenna signal processing module sequentially carries out amplitude limiting, filtering, amplification and other processing on antenna signals, the microstrip phase regulator regulates the phase, the numerical control attenuator controls the signal strength, and finally the processed signals are output. Interference of external calibration signals is avoided, and the sensitivity of an antenna receiving system is improved; the system structure is simplified and the cost is reduced; the calibration signal frequency and amplitude can be internally adjusted, and the integration level is high; the frequency fine tuning and interference evaluation module optimizes the performance, and ensures the stable and efficient operation of the direction-finding communication system.

Description

Technical Field

[0001] The present invention relates to the technical field of direction-finding communication switch arrays, and in particular to a self-calibration switch array for a direction-finding communication system. Background Art

[0002] Direction-finding systems play a crucial role in modern communications technology, widely used in key areas such as military, aerospace, and radio monitoring. The core function of a direction-finding system is to determine the direction of a signal's origin by receiving and analyzing it. As a key component, the switch array network has a decisive impact on system performance.

[0003] In traditional direction-finding communication systems, the calibration signal for the switch array network is often supplied externally. This external calibration signal supply approach presents numerous drawbacks. From an electromagnetic compatibility perspective, the simultaneous presence of the external signal at the calibration input and the external signal received by the antenna in the receiving system can easily lead to electromagnetic interference. For example, when the frequency of the external calibration signal is close to certain frequencies of the antenna receiving signal, harmonic interference can be generated, causing waveform distortion in the received signal and severely impacting signal quality. This not only disrupts the normal operation of the antenna receiving system but can also reduce system sensitivity, significantly compromising the direction-finding communication system's ability to detect weak signals. In complex electromagnetic environments, such as those encountered in military confrontations, this interference can prevent the system from accurately finding direction or even produce erroneous direction-finding results, impacting operational decision-making.

[0004] Furthermore, supplying calibration signals externally increases system complexity and cost. To ensure a stable supply of calibration signals, complex signal source equipment and transmission cables are required. These devices not only take up space but also require regular maintenance and calibration, increasing system operating costs. Furthermore, the line loss and signal attenuation associated with connecting multiple devices are not negligible, further reducing the quality of the calibration signal and impacting the calibration accuracy of the switch array network.

[0005] With the continuous advancement of technology, the performance requirements for direction-finding communication systems are becoming increasingly stringent. In the 5G and future 6G communication era, communication frequency bands are continuously expanding, and signal complexity is increasing dramatically, placing stricter demands on direction-finding accuracy and system response speed. Traditional switch array networks that use external calibration signals are no longer able to meet these new demands. In the field of intelligent transportation, vehicle-to-vehicle communication requires fast and accurate direction finding to achieve efficient communication between vehicles and safe driving assistance. The calibration delay and accuracy issues of traditional methods are becoming a bottleneck hindering technological development.

[0006] Therefore, the development of a new switch array network technology is urgent. This technology needs to address the electromagnetic interference, system complexity, and high cost issues caused by traditional external calibration signals, and improve the overall performance of direction-finding communication systems to meet the needs of evolving communication technologies. Summary of the Invention

[0007] The present invention proposes a self-calibrating switch array for a direction-finding communication system to solve the problems mentioned in the prior art.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a self-calibrating switch array for a direction-finding communication system, comprising:

[0009] Calibration signal generation module: The front stage uses a constant temperature crystal oscillator as the frequency reference, and generates a calibration signal through a VCO oscillation phase-locked circuit. After amplification, filtering, amplitude control and power division, it enters the antenna path to achieve self-calibration; the VCO oscillation phase-locked circuit outputs a frequency f VCO and the crystal frequency f crystal The relationship satisfies the formula f VCO =N×f crystal , where N is the frequency multiplication factor, which is adjusted according to the frequency requirement of the calibration signal. The amplitude control link adjusts the amplitude of the calibration signal according to the formula A=A0×G, where A0 is the initial amplitude and G is the gain factor;

[0010] Switching control module: composed of electronic switches, used to realize the switching between the calibration path and the antenna path. The calibration path and the antenna path adopt a separate board and cavity design;

[0011] The antenna signal processing module includes a limiter, filter, amplifier, switch path, digitally controlled attenuator, microstrip phase adjuster, two-stage amplifier, and equalizer, all connected in sequence. The limiter is located at the antenna signal input to protect the path components; the filter removes out-of-band interference from the antenna signal; the amplifier amplifies the antenna signal amplitude; the switch path switches the antenna signal between the antenna signal and the calibration signal; the digitally controlled attenuator adjusts the antenna signal strength; the microstrip phase adjuster is a self-simulating microstrip phase adjuster; the two-stage amplifier amplifies the signal amplitude; and the equalizer adjusts the signal amplitude range and ultimately outputs it.

[0012] Furthermore, the following modules are also included:

[0013] Frequency fine-tuning module: This module is based on a digitally controlled oscillator (DCO) and fine-tunes the calibration signal frequency by adjusting the DCO control code. The relationship between the frequency fine-tuning amount Δf and the control code C is Δf = k × C, where k is the frequency fine-tuning coefficient.

[0014] Signal interference assessment module: By collecting the spectrum data of the calibration signal and antenna signal, using the interference assessment formula Evaluate the degree of interference between the two, where S i-cal is the amplitude of the ith frequency component of the calibration signal, S i-ant is the amplitude of the i-th frequency component of the antenna signal, and n is the total number of frequency components. When the interference value I exceeds the set threshold, the system automatically adjusts the parameters of the switching control module to optimize the calibration signal generation module.

[0015] Furthermore, the frequency and amplitude of the calibration signal generated by the calibration signal generating module are dynamically adjusted, and the adjustment of the frequency and amplitude is achieved by adjusting the parameters of the VCO oscillation phase-locked circuit and the amplitude control link.

[0016] Furthermore, the isolation of the electronic switch in the switching control module is greater than a preset threshold, and the preset threshold is set according to the electromagnetic compatibility requirement of the direction finding communication system.

[0017] Furthermore, the microstrip phase adjuster in the antenna signal processing module is a self-simulating microstrip phase adjuster, which realizes precise compensatory adjustment of the phase consistency between antenna lines through simulation design.

[0018] Furthermore, the calibration signal generated by the calibration signal generating module is completely physically isolated from the antenna signal in space. In addition to the board-and-cavity design, the isolation is improved by adding a shielding layer in the circuit layout; the calibration signal generated by the calibration signal generating module is completely physically isolated from the antenna signal in space.

[0019] Furthermore, the adjustment accuracy of the digitally controlled attenuator in the antenna signal processing module meets the accuracy requirement of the direction finding communication system for signal strength adjustment, and the adjustment accuracy is set within a range according to system requirements.

[0020] A method for self-calibrating a switch array for a direction-finding communication system comprises the following steps:

[0021] Calibration signal generation steps: Using a constant temperature crystal oscillator as a reference, the VCO oscillation phase-locked circuit generates a calibration signal, and the amplitude is adjusted according to the amplitude control formula A = A0 + ΔA × f(t), where A is the adjusted amplitude, A0 is the initial amplitude, ΔA is the amplitude adjustment coefficient, and f(t) is a function that changes with time;

[0022] Antenna signal processing steps: The antenna signal is processed in sequence by the limiter, filter, amplifier, switch path, digitally controlled attenuator, microstrip phase adjuster, two-stage amplifier and equalizer. Through the signal processing process, the limiter protects the signal from excessive amplitude impact, the filter filters out interference frequency, the amplifier increases the signal strength, and the digitally controlled attenuator is processed according to the formula Adjust the signal amplitude, where A attenuated is the amplitude after attenuation, A originalis the original amplitude, dB is the attenuation decibel number;

[0023] Path switching steps: The electronic switch switches between the calibration path and the antenna path according to system requirements, using a dynamic switching mechanism with high isolation characteristics;

[0024] Frequency fine-tuning step: If there is a frequency fine-tuning module, the frequency of the calibration signal is fine-tuned according to the relationship between the control code C and the frequency fine-tuning amount Δf, Δf=k×C.

[0025] Furthermore, when generating a calibration signal, the VCO output frequency is determined according to a frequency formula. When processing antenna signals, a digitally controlled attenuator and a microstrip phase adjuster respectively adjust the signal strength and phase consistency according to system requirements.

[0026] Compared with the existing technology, the beneficial effects of the present invention are:

[0027] In terms of electromagnetic compatibility and system sensitivity, the self-generated calibration signal design revolutionizes the traditional external calibration signal supply model. Internally generating the calibration signal avoids electromagnetic interference caused by the simultaneous presence of an external signal and the antenna reception signal. Through a separate board and cavity design and the addition of a shielding layer, the calibration and antenna signals are effectively spatially shielded, significantly reducing mutual interference. This enables the antenna reception system to more clearly capture weak signals, effectively improving system sensitivity. For example, in military reconnaissance, weak enemy communication signals can be detected earlier and more accurately, providing critical intelligence support for operations. From the perspective of system complexity and cost, self-calibrating switch array technology significantly simplifies the system architecture. It eliminates the need for complex external calibration signal supply equipment and transmission cables, reduces the number of RF interfaces, and reduces equipment space and maintenance costs. Furthermore, reduced line loss and signal attenuation improve the quality of the calibration signal, indirectly enhancing system reliability. In the aerospace industry, this translates to reduced aircraft weight, lower energy consumption, and improved flight efficiency and endurance.

[0028] This technology offers significant advantages in functional integration and flexibility. By adjusting the parameters of the VCO oscillator phase-locked circuit and amplitude control, the frequency and amplitude of the calibration signal can be precisely adjusted within the switch array network, without relying on an external complete system. This not only improves the integration of the switch array network but also enhances the system's flexibility. The calibration signal can be rapidly adjusted to meet diverse direction-finding communication requirements in different communication scenarios and frequency bands. In radio monitoring, the calibration signal parameters can be quickly switched to accommodate signal monitoring tasks in different frequency bands, improving monitoring efficiency and accuracy.

[0029] Furthermore, the design of the frequency fine-tuning module and the signal interference assessment module further optimizes system performance. The frequency fine-tuning module ensures that the calibration signal frequency more accurately matches system requirements, while the signal interference assessment module monitors and reduces inter-signal interference in real time, ensuring stable and reliable system operation. This provides strong support for the widespread application and technological advancement of direction-finding communication systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic block diagram of a self-calibrating switch array for a direction-finding communication system proposed by the present invention;

[0031] Figure 2 This is a schematic block diagram of a self-calibration switch array method for a direction-finding communication system proposed by the present invention. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0034] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The present invention will be further described in detail below with reference to the accompanying drawings.

[0035] Reference Figure 1-2 : A self-calibrating switch array for a direction-finding communication system, comprising:

[0036] Calibration signal generation module: The front stage uses a 100M constant temperature crystal oscillator as the frequency reference, and generates a calibration signal through a VCO oscillation phase-locked circuit. After amplification, filtering, amplitude control and power division, it enters the antenna path to achieve self-calibration. The VCO oscillation phase-locked circuit output frequency f VCO and the crystal frequency f crystal The relationship satisfies the formula f VCO =N×f crystal (N is the frequency multiplication factor, which can be adjusted according to the calibration signal frequency requirement). The amplitude control link adjusts the calibration signal amplitude according to the formula A=A0×G (A0 is the initial amplitude, G is the gain factor).

[0037] Switching control module: Consists of high-isolation electronic switches, used to switch between the calibration path and the antenna path. The calibration path and antenna path adopt a separate board and cavity design to achieve spatial shielding of the calibration and antenna signals.

[0038] Antenna signal processing module: This includes a limiter, filter, amplifier, switch path, digitally controlled attenuator, microstrip phase adjuster, two-stage amplifier, and equalizer, all connected in sequence. The limiter is placed at the antenna signal entrance to protect the path components; the filter removes out-of-band interference from the antenna signal; the amplifier amplifies the antenna signal amplitude; the switch path switches the antenna signal between the antenna signal and the calibration signal; the digitally controlled attenuator adjusts the antenna signal strength, with an adjustment accuracy that meets the signal strength adjustment accuracy requirements of the direction-finding communication system and can be set within a certain range according to system requirements; the microstrip phase adjuster is a self-simulating microstrip phase adjuster that achieves precise compensatory adjustment of the phase consistency between antenna lines; the two-stage amplifier further amplifies the signal amplitude; and the equalizer adjusts the signal amplitude range and ultimately outputs it.

[0039] The present invention also includes the following modules:

[0040] Frequency fine-tuning module: This module is based on a digitally controlled oscillator (DCO) and fine-tunes the calibration signal frequency by adjusting the DCO's control code. The relationship between the frequency fine-tuning amount Δf and the control code C is Δf = k × C (k is the frequency fine-tuning coefficient), which allows the calibration signal frequency to more accurately match system requirements.

[0041] Signal interference assessment module: This module collects the spectrum data of the calibration signal and antenna signal and uses the interference assessment formula (S i-cal is the amplitude of the ith frequency component of the calibration signal, S i-ant The system uses the amplitude of the antenna signal's i-th frequency component (where n is the total number of frequency components) to assess the degree of interference between the two signals. When the interference value I exceeds a set threshold, the system automatically adjusts the operating state of the switching control module or optimizes the parameters of the calibration signal generation module to reduce inter-signal interference, thereby accurately calculating the degree of interference between the two signals. This process effectively reduces inter-signal interference, ensuring signal purity and stability in the direction-finding communication system, improving communication quality and reliability, and reducing communication errors and data loss caused by signal interference.

[0042] In this invention, the calibration signal generation module generates an adjustable frequency and amplitude of the calibration signal. This is achieved by adjusting the parameters of the VCO oscillator phase-locked circuit and the amplitude control circuit. This frequency and amplitude adjustment function of the calibration signal generation module is extremely valuable. Technicians can precisely adjust the relevant parameters in the VCO oscillator phase-locked circuit to change the frequency of the calibration signal according to actual needs. Simultaneously, they can adjust the parameters of the amplitude control circuit to achieve the desired amplitude of the calibration signal. This flexible adjustment capability allows the calibration signal to better adapt to the different operating scenarios and requirements of the direction-finding communication system, improving the accuracy and effectiveness of calibration and providing reliable calibration signal support for precise system operation.

[0043] In the present invention, the high-isolation electronic switch in the switching control module has an isolation greater than a preset threshold, which is set according to the electromagnetic compatibility requirements of the direction-finding communication system to minimize interference between the calibration signal and the antenna signal. In actual operation, the high-isolation electronic switch effectively isolates the calibration signal from the antenna signal, minimizing interference between the two. It acts as a solid barrier, preventing crosstalk between the signals, maintaining the independence and stability of the system signals, improving the system's anti-interference capabilities, and ensuring stable and reliable operation of the direction-finding communication system even in complex electromagnetic environments.

[0044] In the present invention, the microstrip phase adjuster in the antenna signal processing module is a self-simulating microstrip phase adjuster. This uses simulation design to achieve precise compensatory adjustment of phase consistency between antenna lines. In direction-finding communication systems, phase consistency between antenna lines is crucial for signal reception and processing. The self-simulating microstrip phase adjuster can precisely adjust the phase differences between antenna lines based on the actual system conditions, ensuring phase accuracy during signal transmission and processing, improving signal reception quality and direction-finding accuracy, and providing strong support for the system's high-precision direction-finding.

[0045] In the present invention, the calibration signal generated by the calibration signal generation module is completely physically isolated from the antenna signal. In addition to the split-board, split-cavity design, isolation is further enhanced by adding a shielding layer to the circuit layout. The split-board, split-cavity design physically separates the two signals, while the added shielding layer acts like a protective layer, preventing leakage and interference. This multiple isolation measure significantly improves signal isolation, reduces signal interaction, ensures system signal purity and stability, and contributes to the overall performance of the direction-finding communication system.

[0046] In this invention, the adjustment accuracy of the digitally controlled attenuator in the antenna signal processing module meets the signal strength adjustment accuracy requirements of the direction-finding communication system. This adjustment accuracy can be set within a certain range based on system requirements. In practical applications, technicians can flexibly adjust the parameters of the digitally controlled attenuator to precisely control signal strength according to different communication environments and signal strength requirements. This enables the system to better adapt to different operating conditions, improves the flexibility and adaptability of signal processing, and ensures the stable and efficient operation of the direction-finding communication system in various scenarios.

[0047] The present invention also discloses a self-calibration switch array method for a direction-finding communication system, comprising the following steps:

[0048] Calibration signal generation steps: Using a 100MHz oven-controlled crystal oscillator as a reference, a VCO oscillator phase-locked circuit generates a calibration signal. The amplitude is adjusted according to the amplitude control formula A = A0 + ΔA × f(t) (where A is the adjusted amplitude, A0 is the initial amplitude, ΔA is the amplitude adjustment coefficient, and f(t) is a time-varying function). The signal then enters the antenna path via the power splitter. This step ensures the stability and adjustability of the calibration signal. Using the 100MHz oven-controlled crystal oscillator as a reference ensures a high-precision frequency reference. The unique amplitude control formula allows for flexible amplitude adjustment based on actual needs, making the calibration signal more compatible with subsequent system processing and providing a reliable signal source for accurate calibration.

[0049] Antenna signal processing steps: The antenna signal is processed in sequence by the limiter, filter, amplifier, switch path, digitally controlled attenuator, microstrip phase adjuster, two-stage amplifier and equalizer. Through the creative signal processing process, the limiter protects the signal from excessive amplitude impact, the filter filters out interference frequency, the amplifier increases the signal strength, and the digitally controlled attenuator is processed according to the formula (A attenuated is the amplitude after attenuation, A original The antenna's phase regulator precisely adjusts the signal amplitude (where dB is the original amplitude and dB is the attenuation decibel), and the microstrip phase adjuster precisely compensates the phase. This series of processing effectively achieves comprehensive protection, filtering, amplification, adjustment, and output of the antenna signal, improving signal quality and stability.

[0050] Path Switching Procedure: A high-isolation electronic switch switches between the calibration and antenna paths based on system requirements. Leveraging high isolation and an intelligent switching mechanism, it acts like a precision valve, accurately directing signal flow in different operating modes. This prevents interference between calibration and antenna signals, ensuring signal purity and accuracy in all operating states and improving overall system performance and reliability.

[0051] Frequency fine-tuning steps: If a frequency fine-tuning module is available, fine-tune the calibration signal frequency based on the relationship between the control code C and the frequency fine-tuning amount Δf: Δf = k × C. This formula provides an accurate quantitative basis for frequency fine-tuning. The control code can be changed to achieve fine adjustment of the calibration signal frequency as needed, ensuring that the calibration signal frequency is highly matched to system requirements. This further improves calibration accuracy and system adaptability, ensuring that the direction-finding communication system can achieve high-precision signal processing and direction-finding functions even in complex environments.

[0052] This self-calibrating switch array signal processing method offers several advantages. In the signal generation process, a high-precision reference and flexible amplitude control ensure the quality of the calibration signal. In the signal processing flow, the various components work together and are precisely adjusted using a creative formula, significantly improving the quality of the antenna signal. The precision of path switching avoids signal interference, and the precise quantization of frequency fine-tuning enhances the system's adaptability to different scenarios. Overall, the combination of these steps and the creative formula improves the system's stability, accuracy, and reliability, enabling it to better cope with complex and changing communication environments, realize high-precision direction-finding communication capabilities, and provide strong technical support for applications in related fields.

[0053] Signal interference assessment and adjustment steps: The signal interference assessment module uses the formula The interference value is calculated, and when the interference value I exceeds the set threshold, the system parameters are adjusted. This quantitative method provides an accurate basis for the system to judge the interference situation, enabling the system to promptly and accurately detect the existence and severity of interference problems.

[0054] When interference exceeds a set threshold, the system automatically adjusts its parameters. This mechanism is highly intelligent and autonomous. It can quickly respond to changes in interference without requiring excessive human intervention, significantly saving manpower and time. For example, if changes in the external electromagnetic environment cause increased interference, the system can quickly respond by adjusting the operating state of the switching control module or calibrating the parameters of the signal generation module to reduce interference between signals.

[0055] From a system performance perspective, this system effectively improves the interference resistance and stability of the direction-finding communication system. By timely adjusting parameters, it reduces the impact of signal interference on communication quality, lowers the bit error rate, and ensures the accuracy and reliability of signal transmission. This enables the system to maintain excellent performance in complex and changing electromagnetic environments. Whether in dense urban signal environments or in industrial areas with unique interference sources, it ensures normal direction-finding communication, providing stable and efficient communication support for related applications.

[0056] In this invention, when generating a calibration signal, the VCO output frequency is determined according to a frequency formula. When processing antenna signals, a digitally controlled attenuator and a microstrip phase adjuster adjust signal strength and phase consistency, respectively, according to system requirements. When generating the calibration signal, the VCO (voltage-controlled oscillator) output frequency is determined according to a carefully designed frequency formula. This frequency formula comprehensively considers multiple parameters, including the system's reference frequency, the required frequency offset, and environmental factors. A 100MHz oven-controlled crystal oscillator (OCR) serves as a high-precision frequency reference, providing a stable foundation for frequency generation of the entire calibration signal. Based on this foundation, the frequency formula accurately calculates the VCO's output frequency based on the system's specific operating requirements and external environmental changes. For example, when the system is in different operating modes or faces different signal transmission requirements, the frequency formula adjusts the calculation parameters accordingly, ensuring that the VCO output frequency precisely matches the system's frequency requirements. This precise frequency determination ensures the frequency stability and accuracy of the calibration signal, providing a reliable prerequisite for subsequent signal calibration and processing. The digitally controlled attenuator and microstrip phase adjuster play a key role in processing antenna signals. The digitally controlled attenuator strictly regulates signal strength according to system requirements. Using a precise attenuation control algorithm, it adjusts antenna signal strength to the optimal range required by the system. By monitoring and calculating the input signal in real time, the digitally controlled attenuator precisely controls the amount of attenuation, preventing the adverse effects of excessive or weak signals on subsequent system processing. For example, if the received antenna signal strength is too high, the digitally controlled attenuator quickly reduces the signal strength according to the set attenuation rules, ensuring that the signal is within the operating range of subsequent processing components and preventing distortion or damage caused by signal overload.

[0057] The microstrip phase adjuster focuses on phase alignment between antenna lines. Through advanced simulation design and precise control mechanisms, it accurately compensates for phase differences between antenna lines. In practical direction-finding communication systems, phase alignment between antenna lines is crucial for signal reception and processing. By precisely adjusting the phase alignment between antenna lines, the signals received by each antenna remain highly consistent in phase, thereby improving signal synthesis quality and direction-finding accuracy.

[0058] In summary, in the self-calibrating switch array signal processing method for direction-finding communication systems, the precise frequency determination when generating the calibration signal and the precise adjustment of signal strength and phase consistency by the digitally controlled attenuator and microstrip phase adjuster during antenna signal processing greatly improve the performance and reliability of the system, laying a solid foundation for achieving high-precision direction-finding communication.

[0059] The above are only preferred specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A self-calibrating switch array for a direction-finding communication system, characterized in that: include: Calibration signal generation module: The front stage uses a 100M constant temperature crystal oscillator as the frequency reference, and generates a calibration signal through a VCO oscillation phase-locked circuit. After amplification, filtering, amplitude control and power division, it enters the antenna path to achieve self-calibration; VCO oscillation phase-locked circuit output frequency f VCO and the crystal frequency f crystal The relationship satisfies the formula f VCO =N×f crystal , where N is the frequency multiplication factor, which is adjusted according to the frequency requirement of the calibration signal. The amplitude control link adjusts the amplitude of the calibration signal according to the formula A=A0×G, where A0 is the initial amplitude and G is the gain factor; Switching control module: It is composed of electronic switches and is used to switch between the calibration path and the antenna path. The calibration path and the antenna path adopt a separate board and cavity design; Antenna signal processing module: includes a limiter, filter, amplifier, switch path, digitally controlled attenuator, microstrip phase adjuster, two-stage amplifier and equalizer connected in sequence. The limiter is set at the antenna signal entrance to protect the path components; The filter removes out-of-band interference from the antenna signal; the amplifier amplifies the antenna signal amplitude; The switch path switches between the antenna signal and the calibration signal; the digitally controlled attenuator adjusts the antenna signal strength, the microstrip phase adjuster is a self-simulating microstrip phase adjuster, and the two-stage amplifier amplifies the signal amplitude; The equalizer adjusts the amplitude range of the signal and finally outputs it.

2. A self-calibrating switch array for a direction-finding communication system according to claim 1, characterized in that: Also includes: Frequency fine-tuning module: Based on the digitally controlled oscillator DCO, the calibration signal frequency is fine-tuned by adjusting the DCO control code; The relationship between the frequency fine-tuning amount Δf and the control code C is Δf=k×C, where k is the frequency fine-tuning coefficient.

3. The self-calibrating switch array for a direction-finding communication system according to claim 1, wherein: Also includes: Signal interference assessment module: By collecting the spectrum data of the calibration signal and antenna signal, using the interference assessment formula Evaluate the degree of interference between the two, where S i-cal is the amplitude of the ith frequency component of the calibration signal, S i-ant is the amplitude of the i-th frequency component of the antenna signal, and n is the total number of frequency components. When the interference value I exceeds the set threshold, the system automatically adjusts the parameters of the switching control module to optimize the calibration signal generation module.

4. The self-calibrating switch array for a direction-finding communication system according to claim 1, wherein: The frequency and amplitude of the calibration signal generated by the calibration signal generating module are dynamically adjusted, and the adjustment of the frequency and amplitude is achieved by adjusting the parameters of the VCO oscillation phase-locked circuit and the amplitude control link.

5. The self-calibrating switch array for a direction-finding communication system according to claim 1, wherein: The isolation degree of the electronic switch in the switching control module is greater than a preset threshold value, and the preset threshold value is set according to the electromagnetic compatibility requirement of the direction finding communication system.

6. The self-calibrating switch array for a direction-finding communication system according to claim 1, wherein: The microstrip phase adjuster in the antenna signal processing module is a self-simulating microstrip phase adjuster, which realizes precise compensatory adjustment of the phase consistency between antenna lines through simulation design.

7. The self-calibrating switch array for a direction-finding communication system according to claim 1, wherein: The calibration signal generated by the calibration signal generating module is completely physically isolated from the antenna signal in space. In addition to the separate board and separate cavity design, the isolation is improved by adding a shielding layer in the circuit layout; the calibration signal generated by the calibration signal generating module is completely physically isolated from the antenna signal in space.

8. The self-calibrating switch array for a direction-finding communication system according to claim 1, wherein: The adjustment accuracy of the digitally controlled attenuator in the antenna signal processing module meets the accuracy requirements of the direction-finding communication system for signal strength adjustment, and the adjustment accuracy is set within a range according to system requirements.

9. A method for using the self-calibrating switch array for a direction-finding communication system according to any one of claims 1 to 8, characterized in that: The following steps are involved: Calibration signal generation steps: Using a 100M constant temperature crystal oscillator as a reference, the VCO oscillation phase-locked circuit generates a calibration signal, and the amplitude is adjusted according to the amplitude control formula A = A0 + ΔA × f(t), where A is the adjusted amplitude, A0 is the initial amplitude, ΔA is the amplitude adjustment coefficient, and f(t) is a function that changes with time; Antenna signal processing steps: The antenna signal is processed in sequence by the limiter, filter, amplifier, switch path, digitally controlled attenuator, microstrip phase adjuster, two-stage amplifier and equalizer. Through the signal processing process, the limiter protects the signal from excessive amplitude impact, the filter filters out interference frequency, the amplifier increases the signal strength, and the digitally controlled attenuator is processed according to the formula Adjust the signal amplitude, where A attenuated is the amplitude after attenuation, A original is the original amplitude, dB is the attenuation decibel number; Path switching steps: The isolation electronic switch switches between the calibration path and the antenna path according to system requirements, using a dynamic switching mechanism based on isolation characteristics; Frequency fine-tuning step: If there is a frequency fine-tuning module, the frequency of the calibration signal is fine-tuned according to the relationship between the control code C and the frequency fine-tuning amount Δf, Δf=k×C.

10. The method for self-calibrating a switch array for a direction-finding communication system according to claim 9, characterized in that: When generating the calibration signal, the VCO output frequency is determined according to the frequency formula. When processing the antenna signal, the digitally controlled attenuator and microstrip phase adjuster adjust the signal strength and phase consistency according to the system requirements.

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