A tacan detector

Abstract

The utility model relates to a tower cannon detector technical field, and it relates to a tower cannon detector, including main control module, power module, radio frequency processing module, power measurement and envelope detection module and attenuation control module, main control module is connected with radio frequency processing module, power measurement and envelope detection module, attenuation control module electricity respectively, power module is main control module, radio frequency processing module, power measurement and envelope detection module, attenuation control module provide working power supply, the utility model not only can simulate tower cannon ground station, precision ranging station and air / air mode signal, still have power measurement and envelope detection function, can carry out comprehensive test to the multiple performance indexes of tower cannon airborne equipment, covers the direction, distance and radio frequency parameter.

Description

Technical Field

[0001] This utility model relates to the field of TACAN testing instruments, and specifically to a TACAN testing instrument. Background Technology

[0002] TACAN, as an important aviation navigation device, is widely used in both military and civil aviation. Working in conjunction with ground beacon stations, it provides aircraft with accurate position and distance information, serving as a crucial means to ensure flight safety and improve navigation efficiency. During routine aircraft maintenance and system calibration, ground-based TACAN signal simulators are typically used to perform functional testing and performance verification of the airborne equipment.

[0003] Existing TACAN signal simulators only support the simulation and verification of two basic navigation functions: distance and bearing. They cannot cover the testing requirements of key RF parameters such as RF output power and envelope modulation quality in TACAN systems. In addition, current equipment generally lacks flexible power adjustment and envelope analysis capabilities, making it impossible to perform precise testing and debugging of airborne equipment performance in multiple scenarios and complex environments.

[0004] Furthermore, existing systems have limitations in functional module division and power management, making it difficult to achieve precise coordination and efficient energy consumption control among internal modules. For example, traditional systems often employ a single-structure design for processing RF modulation, envelope signal synthesis, and signal attenuation adjustment, lacking modularity, controllability, and scalability. For rapid field testing needs, current equipment is bulky, has low integration, and is inconvenient to carry and deploy, failing to meet the technical requirements of rapid response and multi-functional parallel processing in on-site testing.

[0005] In summary, existing TACAN signal simulation equipment has significant shortcomings in terms of human-computer interaction, radio frequency parameter analysis capabilities, modular system design, and portability. A new type of TACAN detector with radio frequency parameter detection function, precise control, high integration, and applicability to various operating scenarios is needed to solve the above technical problems. Summary of the Invention

[0006] This invention addresses the problems of existing TACAN detectors, such as limited testing functions, inability to quantitatively analyze radio frequency indicators, and low system integration. It proposes a comprehensive, adjustable TACAN detector with radio frequency detection capabilities that is easy to use.

[0007] This utility model is achieved through the following technical solution:

[0008] A TACAN detector includes: a main control module, a power supply module, an RF processing module, a power measurement and envelope detection module, and an attenuation control module; the main control module is electrically connected to the RF processing module, the power measurement and envelope detection module, and the attenuation control module respectively; the power supply module provides operating power to the main control module, the RF processing module, the power measurement and envelope detection module, and the attenuation control module.

[0009] Furthermore, the power module includes a DC-DC converter and a power on / off control circuit. The input terminal of the DC-DC converter is connected to an external power adapter, and the output terminal is connected to the main control module, the radio frequency processing module, the power measurement and envelope detection module, and the attenuation control module, respectively.

[0010] Furthermore, the radio frequency processing module includes a carrier generation circuit, an envelope generation circuit, an OOK modulation circuit, and an AM modulation circuit; the output terminal of the carrier generation circuit is connected to the input terminal of the OOK modulation circuit, and the output terminal of the OOK modulation circuit is connected to the input terminal of the AM modulation circuit; the output terminal of the envelope generation circuit is connected to the input terminal of the AM modulation circuit; and the output terminal of the AM modulation circuit is connected to the attenuation control module.

[0011] Furthermore, the carrier generation circuit uses a direct digital synthesizer chip, the output of which is connected to the input of a current-to-voltage converter, and the output of the current-to-voltage converter is connected to the input of a low-pass filter; the envelope generation circuit includes two DDS phase accumulators, which output 15Hz and 135Hz sine wave signals respectively, and are connected to the AM modulation circuit through a low-pass filter.

[0012] Furthermore, the power measurement and envelope detection module includes an L-band detector, a logarithmic detector, a pulse limiting circuit, and a hysteresis comparator; the input terminal of the L-band detector is connected to the signal output terminal of the airborne equipment, and the output terminal is sequentially connected to the logarithmic detector, the pulse limiting circuit, and the hysteresis comparator; the output terminal of the logarithmic detector is connected to the main control module, and the output terminal of the hysteresis comparator is connected to the main control module.

[0013] Furthermore, the attenuation control module includes an electrically adjustable attenuator and a fixed attenuator; the input terminal of the electrically adjustable attenuator is connected to the output terminal of the RF processing module, and the output terminal is connected to an external test interface through the fixed attenuator; the control terminal of the electrically adjustable attenuator is connected to the main control module.

[0014] Furthermore, it also includes an operation display module, which is a touch screen connected to the main control module via an internal bus, and the power input terminal of the touch screen is connected to the output terminal of the power module.

[0015] Furthermore, the main control module includes an MCU and an FPGA. The MCU is connected to the FPGA via an SPI interface. The FPGA is connected to the envelope generation circuit, the OOK modulation circuit, and the AM modulation circuit of the radio frequency processing module, respectively.

[0016] The beneficial effects of this utility model are:

[0017] (1) The TACAN detector proposed in this utility model can not only simulate TACAN ground station, precision distance measuring station and air / air mode signals, but also has power measurement and envelope detection functions, and can comprehensively test multiple performance indicators of TACAN airborne equipment, covering azimuth, distance and radio frequency parameters;

[0018] (2) The TACAN detector proposed in this utility model realizes the precise generation, modulation and intensity adjustment of radio frequency signals by integrating circuits such as electrically adjustable attenuator, logarithmic detector and DDS frequency synthesizer, and can perform quantitative analysis and controllable adjustment of key radio frequency parameters such as output power;

[0019] (3) The TACAN tester proposed in this utility model is suitable for in-situ testing in the field and maintenance calibration in the field. It supports TACAN system testing of multiple aircraft models, has good versatility and environmental adaptability, and is particularly suitable for the ever-changing and complex combat or training environment.

[0020] (4) The present invention proposes a TACAN detector, the power module is equipped with a DC-DC converter and a voltage monitoring circuit, so as to realize stable output of power supply from different modules and real-time monitoring of voltage status, thereby improving the overall energy efficiency management capability and system reliability.

[0021] (5) The present invention proposes a TACAN detector that uses DDS and filters to generate high-quality carrier and envelope signals, and combines OOK and AM modulation circuits to ensure the accuracy and consistency of analog signals and improve the reliability of test results. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is an overall block diagram of a Tacon detector proposed in this utility model;

[0024] Figure 2 This is a block diagram of the power supply module of a TACAN detector proposed in this utility model;

[0025] Figure 3 The power module circuit principle of the TACAN detector proposed in this utility model Figure 1 ;

[0026] Figure 4 The power module circuit principle of the TACAN detector proposed in this utility model Figure 2 ;

[0027] Figure 5 The principle of the main control module of the TACAN detector proposed in this utility model Figure 1 ;

[0028] Figure 6 The principle of the main control module of the TACAN detector proposed in this utility model Figure 2 ;

[0029] Figure 7 This invention provides a schematic diagram of the OOK modulation circuit for the radio frequency processing module of a TACAN detector.

[0030] Figure 8 This utility model presents a schematic diagram of the AM modulation circuit for the radio frequency processing module of a TACAN detector.

[0031] Figure 9 This is a block diagram of the carrier generation circuit of a TACAN detector proposed in this utility model;

[0032] Figure 10 This is a block diagram of the envelope signal generation circuit of a TACAN detector proposed in this utility model;

[0033] Figure 11 This is a schematic diagram of the envelope signal generation circuit of a TACAN detector proposed in this utility model;

[0034] Figure 12 This is a schematic diagram of the pulse shaping circuit of a TACAN detector proposed in this utility model;

[0035] Figure 13 This is a circuit diagram of a power measurement and envelope detection module for a TACAN detector proposed in this utility model;

[0036] Figure 14 This is a schematic diagram of the attenuation control circuit of a TACAN detector proposed in this utility model. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are only used to explain this utility model and are not intended to limit this utility model. Example

[0038] This embodiment proposes a specific implementation method for a TACAN detector.

[0039] refer to Figure 1 A TACAN tester comprises a main control module, a power supply module, an operation display module, an RF processing module, a power measurement and envelope detection module, and an attenuation control module. Each module has a clear functional division and works together to form a complete hardware system architecture, enabling various physical layer testing operations on TACAN airborne equipment.

[0040] refer to Figures 2-4 The power module provides multiple operating voltage inputs for the entire device. It includes a DC-DC voltage converter, a power-on / off control circuit, and a voltage measurement circuit. The power module is powered by an external 27V DC power supply or an 8.4V lithium battery. Optionally, a standard power adapter converting 220V AC input to 27V DC can be used. This adapter uses existing technology products that meet industry standards and has a power redundancy of over 30%. The DC-DC module converts the input DC voltage into three operating voltages: +12V, +5V, and +3.3V, supplying power to the main control module, RF processing module, power measurement module, and operation display module, respectively. The power module includes a voltage measurement circuit, and the voltage signals are acquired by the microcontroller's built-in AD converter. The four voltage values ​​are transmitted to the main control module via an internal bus to enable real-time monitoring and anomaly detection of the system's power status.

[0041] refer to Figures 5-6 The main control module is the control core of this detector. Internally, it includes a processor, power management interface, signal control interface, and system communication interface. The processor coordinates the entire system's operation flow, executes hardware interaction tasks, and connects to the operation display module, RF processing module, power measurement and envelope detection module, and attenuation control module via a control bus, enabling centralized control and status feedback for each module. The main control module and operation display module constitute the device's human-machine interface, supporting touch and button operation. Based on user-input commands such as channel selection, power setting, and tone control, the controller sends control instructions to the corresponding modules through the interface, while simultaneously collecting operational feedback from each module and displaying it in real-time on the display module.

[0042] refer to Figures 7-8 The radio frequency processing module is used to synthesize and modulate key elements such as carrier, envelope, and pulse in the detection signal. The module includes a carrier signal generation circuit, an envelope signal generation circuit, a pulse shaping circuit, an OOK modulation circuit, and an AM modulation circuit.

[0043] refer to Figure 9The carrier signal is generated using DDS technology, and the output is a multi-frequency, current-type differential signal. After being processed by current / voltage conversion and low-pass filter, it is sent to the modulation circuit.

[0044] refer to Figures 10-11 The envelope signal generation circuit uses a DDS digital-to-analog chip to output 15Hz and 135Hz sine waves, which are then filtered by a filtering circuit and provided to the AM modulation circuit for amplitude modulation.

[0045] refer to Figure 12 The pulse shaping circuit generates TACAN primary and secondary reference pulse coding format signals, which are sent to the OOK modulation circuit for the first modulation. The modulated signal is then combined with the envelope signal and sent to the AM modulation circuit for composite modulation, ultimately forming a composite radio frequency signal that conforms to the TACAN signal standard for subsequent power adjustment and output.

[0046] refer to Figure 13 The power measurement and envelope detection module is used to perform power and envelope recovery processing on the RF signal received from the device under test (DUT). This module includes an L-band detector, a limiting and shaping comparator, and a logarithmic detector. The signal transmitted by the DUT is attenuated by an external attenuator and then sent to the L-band detector to restore the envelope signal. This envelope signal is an analog signal superimposed with noise and interference, and needs to be shaped by a voltage comparator. The positive feedback characteristic of the hysteresis comparator enhances anti-interference capability and stabilizes the signal waveform output. The logarithmic detector can convert RF input signals in the range of 1MHz to 6GHz into a linear dB voltage output, and uses progressive compression technology on a cascaded amplifier to achieve accurate logarithmic consistency. The VOUT pin can be connected to a set voltage to realize the standardized conversion of signal amplitude. The resulting output voltage is connected to the ADC interface of the main control module for signal strength display and sensitivity testing.

[0047] refer to Figure 14 The attenuation control module, used to adjust the strength of the RF output signal, mainly consists of an electronically adjustable attenuator and an external fixed attenuator. The electronically adjustable attenuator supports a 40dB dynamic adjustment range, achieving a power output from -15dBm to -50dBm; its control port is driven by a control word output from the main control module, enabling power level adjustment. The fixed attenuator has an attenuation of 40dB, used to attenuate the modulated signal to a range that meets the sensitivity test requirements of the TACAN airborne equipment receiver. The attenuated RF signal is then output to an external interface for testing.

[0048] In this embodiment, the power supply module, main control module, display module, RF processing module, power measurement module, and attenuation module of the TACAN detector form a complete hardware closed-loop control relationship. The signal path is clear, and the structural modules are reasonably distributed, which meets the functional requirements of TACAN equipment testing for high-frequency signal control, accurate power output, signal modulation and synthesis, and envelope recognition. Example

[0049] This embodiment proposes a function of a TACAN detector based on embodiment 1.

[0050] The TACAN detector in this embodiment has the following functions:

[0051] A TACAN detector includes a main control MCU, an FPGA, a power supply module, an RF processing module, a power measurement module, an attenuation control module, and an operation interface for communication with a host computer.

[0052] The main control MCU communicates with the host computer to receive various functional commands, including channel configuration, azimuth setting, distance setting, identification tone control, power measurement, and attenuation adjustment. The main control MCU is connected to the FPGA module, RF processing module, power measurement module, and attenuation control module via multiple data and control lines to coordinate and implement function calls and status feedback.

[0053] The MCU has a channel frequency information storage area to store the transmit and receive frequencies corresponding to 252 channels from 1X to 126X and from 1Y to 126Y. When it receives a channel configuration command from the host computer, the MCU looks up the frequency information based on the stored data and outputs a control signal to the RF processing module to control it to switch to the corresponding RF output frequency.

[0054] The azimuth simulation function is completed by the MCU and FPGA working together. After the MCU receives the azimuth setting command from the host computer, it transmits the current azimuth value or azimuth change rate parameter in the command to the FPGA. The FPGA synthesizes the simulated azimuth signal based on the received data for subsequent modulation. The MCU can read the current azimuth value output by the FPGA in real time and upload it to the host computer through the interface.

[0055] The distance simulation function is similar in structure to the orientation function. After the MCU receives the current distance or distance change rate command, it processes the data and transmits it to the FPGA. The FPGA outputs a simulated distance signal based on this signal. The MCU periodically reads the distance value and feeds it back to the host computer to realize dynamic distance simulation.

[0056] The recognition tone function is executed by the FPGA. After the MCU receives the recognition tone on or off command from the host computer, it sends the control signal to the FPGA. The FPGA outputs a continuous recognition tone or Morse code recognition tone signal, or an interrupt output, according to the received status control command. The MCU records and feeds back the current recognition tone status synchronously.

[0057] The power measurement function is performed by the FPGA to sample the received radio frequency signal in real time. The FPGA has a built-in power detection module to obtain the input power level. The measured power signal is read by the MCU, filtered and converted to units, and the processing result is uploaded and displayed when a request is received from the host computer.

[0058] The sensitivity adjustment function is directly controlled by the main control MCU to control the electronically controlled attenuator in the RF processing module. After receiving the attenuation configuration command from the host computer, the MCU outputs the corresponding control word to the attenuation control module to change the attenuation in the signal output path and achieve fine control of the output power.

[0059] In the above embodiments, the MCU and each functional module form a closed signal interaction path through a unified control bus and data channel, which ensures that the system functions respond in a timely manner and has a high degree of structural integration, meeting the requirements of analog capability, precision control and signal stability in the TACAN detection scenario.

[0060] The azimuth and range analog signals are generated collaboratively by the MCU and FPGA. By controlling the relative phase or delay between the primary and secondary reference pulses, a digital control signal is formed and input to the RF processing module. The RF processing module generates the corresponding RF signal through processes such as carrier modulation and envelope synthesis. This signal is then output to the airborne equipment after its power is adjusted by the attenuation control module. The echo signal from the airborne equipment is acquired and processed by the power measurement module and fed back to the main control module for closed-loop testing and status determination.

[0061] In this embodiment, the output power of the TACAN transceiver is gradually reduced from -55dBm, -60dBm, -65dBm, -70dBm, -75dBm, -80dBm, -85dBm, to -90dBm until the airborne equipment does not respond. At this point, the output power of the transceiver is the receiving sensitivity of the airborne equipment, and the PP value displayed during the test is the peak power of the signal transmitted by the TACAN transceiver.

[0062] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A TACAN detector, characterized in that, include: The system comprises a main control module, a power supply module, an RF processing module, a power measurement and envelope detection module, and an attenuation control module. The main control module is electrically connected to the RF processing module, the power measurement and envelope detection module, and the attenuation control module. The power supply module provides operating power to the main control module, the RF processing module, the power measurement and envelope detection module, and the attenuation control module.

2. The TACAN detector according to claim 1, characterized in that, The power module includes a DC-DC converter and a power on / off control circuit. The input terminal of the DC-DC converter is connected to an external power adapter, and the output terminal is connected to the main control module, the radio frequency processing module, the power measurement and envelope detection module, and the attenuation control module, respectively.

3. The TACAN detector according to claim 1, characterized in that, The radio frequency processing module includes a carrier generation circuit, an envelope generation circuit, an OOK modulation circuit, and an AM modulation circuit; the output terminal of the carrier generation circuit is connected to the input terminal of the OOK modulation circuit, and the output terminal of the OOK modulation circuit is connected to the input terminal of the AM modulation circuit; the output terminal of the envelope generation circuit is connected to the input terminal of the AM modulation circuit; and the output terminal of the AM modulation circuit is connected to the attenuation control module.

4. A TACAN detector according to claim 3, characterized in that, The carrier generation circuit uses a direct digital synthesizer chip, whose output is connected to the input of a current-to-voltage converter, and the output of the current-to-voltage converter is connected to the input of a low-pass filter; the envelope generation circuit includes two DDS phase accumulators, which output 15Hz and 135Hz sine wave signals respectively, and are connected to the AM modulation circuit through a low-pass filter.

5. A TACAN detector according to claim 1, characterized in that, The power measurement and envelope detection module includes an L-band detector, a logarithmic detector, a pulse limiting circuit, and a hysteresis comparator. The input of the L-band detector is connected to the signal output of the airborne equipment, and the output is sequentially connected to the logarithmic detector, the pulse limiting circuit, and the hysteresis comparator. The output of the logarithmic detector is connected to the main control module, and the output of the hysteresis comparator is connected to the main control module.

6. A TACAN detector according to claim 1, characterized in that, The attenuation control module includes an electrically adjustable attenuator and a fixed attenuator; the input of the electrically adjustable attenuator is connected to the output of the RF processing module, and the output is connected to an external test interface through the fixed attenuator; the control terminal of the electrically adjustable attenuator is connected to the main control module.

7. A TACAN detector according to claim 1, characterized in that, It also includes an operation display module, which is a touch screen and is connected to the main control module via an internal bus. The power input terminal of the touch screen is connected to the output terminal of the power module.

8. A TACAN detector according to claim 1, characterized in that, The main control module includes an MCU and an FPGA. The MCU is connected to the FPGA via an SPI interface. The FPGA is connected to the envelope generation circuit, the OOK modulation circuit, and the AM modulation circuit of the radio frequency processing module, respectively.

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