CN-122015851-A - Portable anti-interference medium wave Takangtai station evaluation system

CN122015851ACN 122015851 ACN122015851 ACN 122015851ACN-122015851-A

Abstract

The invention discloses a portable anti-interference medium wave Takangtai station evaluation system which comprises a radio frequency front end module and a digital signal processing module, wherein the radio frequency front end module is used for receiving and transmitting radio frequency signals and converting the radio frequency signals, the digital signal processing module comprises an FPGA, a built-in digital signal processing module, an inquiry pulse generating module, a time sequence control and data eliminating module, the integrated evaluation system is designed to realize the deep sharing and multiplexing of hardware resources such as a radio frequency channel, a signal processing unit, a power module and the like, the data eliminating module based on a transmitting time sequence automatically activates a protection window during the process of transmitting the inquiry pulse by equipment, real-time identification and elimination of generated invalid navigation information are carried out, and the final evaluation result is ensured to be completely dependent on effective data of a receiving period, so that the accuracy and reliability of station evaluation data are improved.

Inventors

ZANG BO
LIU ZHENLONG
Long Lulan
GUO YUXUAN
WU WEI
JI HONGBING

Assignees

西安电子科技大学

Dates

Publication Date: 20260512
Application Date: 20260130

Claims (9)

1. A portable anti-interference medium wave tacon station assessment system, the system comprising: the radio frequency front-end module is used for receiving and transmitting radio frequency signals and converting the radio frequency signals, and setting an ADC (analog to digital converter) for carrying out signal transmission after frequency conversion, wherein the radio frequency signals comprise medium wave signals and Takang signals; the digital signal processing comprises an FPGA, wherein a digital signal processing module, an inquiry pulse generating module, a time sequence control and data eliminating module are arranged in the FPGA; the system comprises a digital signal processing module, an inquiry pulse generating module, a timing control and data eliminating module, a digital signal processing module, a timing control and data eliminating module and a control module, wherein the digital signal processing module is used for carrying out digital processing on an analog signal to acquire navigation parameters; And the control management module is connected with the radio frequency front-end module and the digital signal processing and is used for controlling and monitoring.
2. The portable anti-interference medium wave tacon station assessment system according to claim 1, wherein said radio frequency front end module comprises a medium wave antenna, a tacon antenna, a medium wave up-conversion channel, a tacon down-conversion channel and a tacon up-conversion channel; The output end of the Takang antenna is connected with the Takang down-conversion channel through a circulator, the Takang down-conversion channel is connected with the ADC, the ADC is connected with the digital signal processing receiving end, the input end of the Takang antenna is connected with the Takang up-conversion channel through the circulator, and the Takang up-conversion channel is connected with the output end of the digital signal processing through a DAC.
3. The portable anti-interference medium wave tacon station evaluation system according to claim 2, wherein the medium wave antenna comprises a loop antenna and a vertical antenna, and is configured to receive a medium wave navigation signal in a frequency band of 150kHz-1700kHz, wherein the cosine signal and the sine signal of the loop antenna are amplified, respectively subjected to balanced modulation by using a low frequency sine signal and a low frequency cosine signal, and then are combined with the received signal of the vertical antenna to output the medium wave navigation signal after being superimposed.
4. The portable anti-interference medium wave tacon station evaluation system according to claim 2, wherein the medium wave up-conversion channel is specifically a quadratic frequency conversion superheterodyne architecture, and is used in combination with a digital phase-locked loop and automatic gain control to up-convert the medium wave navigation signal to a preset medium frequency point.
5. The portable anti-interference medium wave tacon station assessment system according to claim 2, wherein said circulator is phase-matched to the tacon antenna.
6. The portable anti-interference medium wave tacon station evaluation system according to claim 2, wherein the tacon up-conversion channel is configured to up-convert the interrogation pulse output by the DAC to a tacon operating frequency point to output a radio frequency signal in a tacon transmitting stage, and send the radio frequency signal to a tacon antenna through a circulator, so as to implement bidirectional communication with the tacon system.
7. The portable anti-interference medium wave tacon station assessment system according to claim 1, wherein said digital signal processing comprises medium wave signal processing and tacon signal processing; The medium wave signal processing specifically comprises the steps that a digital signal sampled by an ADC (analog-to-digital converter) is subjected to envelope detection and sampling processing, filtered by a band-pass filter, multiplied by a sine signal and a cosine signal respectively to carry out phase discrimination, and then direct current components obtained by low-pass filtering are subjected to arctangent to obtain azimuth angle information; The Takang signal processing specifically comprises the steps that a Takang signal sampled by an ADC (analog-to-digital converter) is firstly converted into a baseband signal through digital down conversion, the baseband signal is subjected to pulse identification and decoding to obtain rectangular pulses, and the rectangular pulses are respectively subjected to main and auxiliary reference pulse group identification, peak detection and band-pass filtering to obtain angle information of the Takang signal.
8. The portable anti-interference medium wave tacon station evaluation system according to claim 1, wherein the interrogation pulse generation module specifically adopts a direct digital waveform synthesis technology, and the generated interrogation pulse is output to a tacon up-conversion channel through a DAC and is output through a circulator and a tacon antenna.
9. The portable anti-interference medium wave tacon station assessment system according to claim 1, wherein said timing control and data rejection module specifically comprises clock synchronization and data optimization; The clock synchronization is completed by a digital phase-locked loop; The data optimization specifically comprises time sequence control, data processing, data screening and data fusion, wherein the time sequence control is used for monitoring the state of a transmitting enabling signal in real time and coordinating the working time sequence of each module through a time sequence state machine, the data processing is used for carrying out effective and ineffective real-time identification on data during the period of transmitting an inquiry pulse through setting a transmitting protection period judging process, the data screening is used for receiving effective data and eliminating ineffective data, the data fusion is used for receiving the effective data to carry out parameter calculation and result optimization, and finally accurate navigation parameters are output.

Description

Portable anti-interference medium wave Takangtai station evaluation system Technical Field The invention relates to the field of radio navigation evaluation, in particular to a portable anti-interference medium wave Takangtai station evaluation system. Background In the field of aviation radio navigation, a medium wave navigation station and a Takang navigation station are two indispensable ground infrastructures, the medium wave navigation station works in a 150kHz-1700kHz frequency band, and reliable navigation guidance and homing guidance are provided for an aircraft by virtue of the ground wave propagation characteristics and good low-altitude performance, so that the medium wave navigation station is particularly important in military navigation. The Takang system is a short-range polar coordinate type radio navigation system and works in a super-high frequency band of 962 MHz-1213 MHz. The system provides accurate distance and azimuth information for airborne equipment through an inquiry-response mechanism, and plays an irreplaceable role in tactical formation, navigation and the like. CN205450264U discloses a TACAN monitoring device, which comprises a radio frequency channel module, a digital signal processing and control module and a display control module which are made into a portable integrated box, wherein an on-site instrument antenna receives a TACAN signal, pulse parameter measurement is carried out in an FPGA/DSP, and navigation parameter information such as azimuth, distance, identification code and the like is directly output. The ground station or the airborne equipment can be rapidly checked without disassembling the machine, but the receiving and transmitting of the ground station or the airborne equipment share a very high frequency band, the time slot control is simple, if the distance between the tested station and the monitoring equipment is less than 50m, the emission leakage can directly enter the receiving channel, so that the ground station or the airborne equipment is blocked by the receiving channel, and the distance zero drift or the azimuth jitter occurs. And the isolation index of the duplexer is not described, a circulator and a filter are still required to be additionally arranged on engineering, otherwise, the field precision requirement is difficult to meet. CN107817389a discloses a signal acquisition and measurement device of a medium-wavelength navigator, which takes a vector signal generator, a high-speed digitizer and a signal measurement unit as cores, wherein the vector signal generator can assist in calibration, the high-speed digitizer is responsible for acquiring output signals of the navigator and storing the output signals into a data memory, a radio frequency signal sampling unit and an AD sampling unit in the signal measurement unit perform secondary accurate sampling, and the data are presented through a display unit after being processed by a single chip microcomputer, so that the protection performance is improved by adopting a professional chassis as a whole. But the device is integrated in the case, so that the device is poor in portability and is not suitable for field emergency detection scenes. CN110971250B discloses a single-channel co-frequency interference detection and separation method, firstly, performing time domain and frequency domain analysis on the received signal, identifying parameters and time distribution of various interference signals such as single tone and co-frequency modulation, and then combining time sequence characteristics of tacon transmission pulse, positioning interference signal interval in transmission period, stripping invalid data by signal separation algorithm, and reserving signal of reception period for evaluation. The interference identification link is required to extract various interference parameters at the same time, has high requirement on hardware operation capability, and is easy to generate errors in parameter extraction aiming at transient strong interference such as Takang emission pulse, so that part of effective data can be removed by mistake or part of interference data is not completely separated. With the continuous development of aviation navigation technology, higher requirements are put forward on performance evaluation and maintenance guarantee of navigation stations, two sets of special equipment of a medium wave tester and a Takang tester which are mutually independent are generally adopted in the existing evaluation scheme, and the architecture of the discrete special equipment not only causes resource waste and poor portability, but also is more critical in being incapable of effectively solving the inherent technical problems in the evaluation of the Takang system. When the Takang device transmits an inquiry pulse, a strong transmitting signal can generate serious interference on a receiving channel of the Takang device, and the characteristic of the same-frequency receiving and transmitti