Interferometer direction finding system
By reconfiguring the routing and switching network and software, the phase detection channel fault of the interferometer direction finding system is converted into a signal detection channel, which solves the problem of reduced signal detection and direction finding accuracy caused by the phase detection channel fault, and improves the reliability of the system and the ease of engineering implementation.
Patent Information
- Application Number
- CN202511408240.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-29
- Publication Date
- 2026-01-20
AI Technical Summary
In existing interferometer direction finding systems, the combination of high and low gain antennas means that the phase detection channel cannot function properly when it malfunctions, resulting in a decrease in signal detection and direction finding accuracy, and the engineering implementation cost is also high.
By reconfiguring the routing and switching network and software, the fault phase detection channel is converted into a signal detection channel, and the impact of the fault channel on signal detection and direction finding is reduced by adjusting the beam coverage of the main array antenna.
This improves the reliability of signal detection and direction finding even in the event of a phase detection channel failure, while reducing the complexity and cost of engineering implementation.
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Figure CN121364441A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the field of electronic reconnaissance, and particularly relates to an interferometer direction finding system. BACKGROUND
[0002] In the field of passive direction finding and positioning of electronic reconnaissance, the phase interferometer direction finding system is widely used in practical engineering to obtain target direction and position information.
[0003] The phase interferometer direction finding system generally requires that the antennas of different channels have the same antenna pattern and antenna gain. However, when a high-sensitivity reconnaissance target signal is required, a large-diameter or array receiving antenna is often used. If large-diameter or array antennas are used in multiple channels, the engineering implementation cost is high. Therefore, a combination of high and low gain antennas is an acceptable way in practical engineering. The main receiving channel can use a high-gain receiving antenna for target signal detection, discovery and basic parameter measurement. This channel is called the detection channel. The remaining receiving channels use low-gain antennas to form an interferometer direction finding system through a specific baseline configuration. The system uses pulse accumulation phase discrimination, high-precision phase difference extraction and other technologies to realize direction finding and positioning of the target radiation source. This channel is called the phase discrimination channel. The basic principle diagram is shown in Figure 1
[0004] For the engineering implementation of the interferometer direction finding system, the document “Interferometer Technology and Engineering Implementation” [J]. Space Electronic Countermeasures, 2019, 35(4): 16-19, studies a DFT-based accumulation phase discrimination method to solve the problem of different antenna gain of the main and auxiliary channels of the interferometer, analyzes the constraints that need to be met by the interferometer array, designs a segmented accumulation architecture that meets the real-time processing requirements in combination with the engineering practice, and verifies the effectiveness of the accumulation phase discrimination method proposed in this paper through simulation experiments. Subsequent research is needed to continue to study the phase correction under different antenna patterns, accumulation phase discrimination of ultra-wideband signals and other problems, and to promote the model application of the interferometer technology. The above-mentioned paper roughly discusses the engineering implementation of the asymmetric interferometer direction finding and positioning system, and the principle is feasible, but does not give a detailed design scheme, and does not involve the design method of channel routing switching. SUMMARY
[0005] The application aims at overcoming the problems in the prior art and discloses an interferometer direction finding system.
[0006] The application achieves the above-mentioned purpose by the following technical scheme. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system. The application discloses an interferometer direction finding system.
[0007] According to a preferred embodiment, the performance indicators of each frequency conversion channel of the frequency conversion unit 1 and the frequency conversion unit 2 are designed to be consistent.
[0008] According to a preferred embodiment, the number of down-conversion channels in the frequency conversion unit 1 and the frequency conversion unit 2 is designed redundantly, according to the maximum number of channels of the frequency conversion unit 1 or the frequency conversion unit 2.
[0009] According to a preferred embodiment, the signal detection unit and the phase discrimination unit are designed consistently in hardware, and the number of channels is designed redundantly, taking the maximum number of detection channels and phase discrimination channels.
[0010] According to a preferred embodiment, the signal detection unit is built-in with software capable of reconfiguring the chip and the link, and capable of performing software reconfiguration operation as needed; the phase discrimination unit is built-in with software capable of reconfiguring the chip and the link, and capable of performing software reconfiguration operation as needed.
[0011] According to a preferred embodiment, the direction finding unit is designed to be capable of receiving data from both the signal detection unit and the phase discrimination unit, and capable of automatically distinguishing the data sources for processing.
[0012] The foregoing main scheme of the present application and each further selected scheme thereof can be freely combined to form multiple schemes, all of which are the schemes that can be adopted and claimed by the present application. Those skilled in the art can understand that there are multiple combinations according to the existing technology and common knowledge after understanding the schemes of the present application, all of which are the technical schemes claimed by the present application, and are not listed here.
[0013] The beneficial effects of the present application are as follows: Through the small number of channel redundancy, software reconfigurable design, and the use of routing switching network, the present application can realize the function exchange of the signal detection channel and the phase discrimination channel of the interferometer direction finding system back end, that is, the failure of the phase discrimination channel can be transferred to the detection channel. Combined with the flexible selection of the main array antenna beam coverage, the failure channel has no impact or very limited impact on the entire beam coverage area reconnaissance, and finally the impact of the failure of a channel of the phase discrimination channel is minimized. The present application can improve the reliability of the interferometer direction finding system, and can be popularized to the system design of various configurations of phase interferometer direction finding systems, multi-channel radar systems, multi-channel communication systems, etc. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 is the implementation principle diagram of the interferometer direction finding system; Figure 2 is the signal flow diagram of the working condition 1 of the interferometer direction finding system of the present application; Figure 3Fig. 2 is a signal flow diagram of the interferometer direction finding system of the present application in working condition 2; Figure 4 Fig. 3 is a basic architecture diagram of the signal processing board in the interferometer direction finding system of the present application. DETAILED DESCRIPTION
[0015] The advantages and effects of the present application can be easily understood by the skilled in the art from the above description. The present application can also be implemented or applied in other different specific embodiments, and the details in the description can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.
[0016] The present application discloses an interferometer direction finding system, which comprises the following units.
[0017] (1) Antenna unit The interferometer direction finding system comprises two types of antennas. One type is used for signal interception, parameter measurement, amplitude comparison direction finding, etc., and needs higher antenna gain to obtain higher signal detection sensitivity, which is called main array antenna, such as the antenna 1 in Figure 2 , 3 . The other type generally comprises several lower gain antennas, which form an interferometer antenna array according to specific baseline relationship, and are used for signal phase difference extraction, and are generally called interferometer antenna array, such as the antennas 21 to 2N in Figure 2 , 3 .
[0018] (2) Routing and switching network unit The routing and switching network unit is used for routing and switching the signals from the main array antenna and the interferometer antenna array. The routing and switching network unit needs to select the signals from the main array antenna to adapt to the down-conversion and direction finding processing of the back end.
[0019] Under normal circumstances, the main array antenna signal is output to the frequency conversion unit 1, and the interferometer antenna signal is output to the frequency conversion unit 2. Under abnormal circumstances, through the action of the routing and switching network unit, the main array antenna beam signal is output to the frequency conversion unit 2, and the interferometer antenna signal is output to the frequency conversion unit 1.
[0020] Specifically, the interferometer direction finding system involves two working modes, normal mode and abnormal mode, the normal mode, i.e. working condition 1, at this time the frequency conversion unit 1 processes the detection signal from the antenna 1, and the frequency conversion unit 2 processes the phase discrimination signal from the antenna 2, and the signal flow diagram of the working condition 1 is as shown in Figure 2 The abnormal mode, i.e. working condition 2 (when a certain channel of the rear end of the interferometer direction finding system fails to work normally), through the switching effect of the routing switching network on the antenna signal, the frequency conversion unit 2 processes the detection signal from the antenna 1 at this time, and the frequency conversion unit 1 processes the phase discrimination signal from the antenna 2, that is, the fault channel is placed in the channel corresponding to the antenna 1 detection signal, and the signal flow diagram of the working condition 2 is as shown in Figure 3 At this time, one of the signal detection channels of the working condition 2 is faulty, but through reasonable selection of the range of the antenna beam coverage, the influence of the fault channel on signal detection, parameter measurement and amplitude comparison direction finding can be minimized.
[0021] (3) Frequency conversion unit The function of the frequency conversion unit is to perform down-conversion processing on the signal, convert the received radio frequency signal to intermediate frequency output, and provide sampling and processing for the signal processing unit. In order to ensure the interchangeability of the frequency conversion unit 1 and the frequency conversion unit 2, the performance indicators of each frequency conversion channel of the frequency conversion unit 1 and the frequency conversion unit 2 are generally designed to be completely consistent, and the number of down-conversion channels in the frequency conversion unit 1 and the frequency conversion unit 2 is generally designed redundantly, according to the maximum number of channels of the frequency conversion unit 1 or 2.
[0022] (4) Digital processing unit The digital processing unit includes a signal detection unit, a phase discrimination unit and a direction finding unit.
[0023] The signal detection unit mainly realizes interception and parameter measurement of the main array antenna signal, etc., and forms a detection channel pulse description word; the unit inside it contains a software reconfigurable chip and a link, which can be reconfigured according to needs.
[0024] The phase discrimination unit mainly realizes phase difference extraction of the interferometer antenna signal, etc., and forms a phase difference result of a phase discrimination channel; the unit inside it contains a software reconfigurable chip and a link, which can be reconfigured according to needs.
[0025] The signal detection unit and the phase discrimination unit generally adopt a cooperative working mode, the signal detection result can guide the phase difference extraction of the phase discrimination channel, and the amplitude comparison result of the detection channel can further solve the ambiguity of the interferometer direction finding. The signal detection unit and the phase discrimination unit are generally completely consistent in hardware design, both have software reconfiguration capability, and the number of channels is redundantly designed, generally taking the maximum number of detection channels and phase discrimination channels.
[0026] The basic architecture of the signal processing board which can interchange the functions of detection and phase discrimination in the signal detection unit and the phase discrimination unit is shown in Fig. 1. Figure 4 The memory 1 is generally used as the buffer area for the processing of signal detection, parameter measurement and signal phase discrimination, and the memory 2 is generally used for storing the reconfigurable software. The loading control software is used for loading management of the reconfigurable chip.
[0027] The direction finding unit is mainly used for calculating the incoming direction of the signal by using the phase difference result of the phase discrimination channel and combining the amplitude ratio result of the detection channel. The direction finding unit is generally designed to receive data from the signal detection unit and the phase discrimination unit, and can automatically distinguish the data source for processing.
[0028] Application case In a certain interferometer direction finding system, the antenna 1 (main array antenna) adopts a 24-beam coverage design, and 7 beams are used for instantaneous coverage. When used, 7 signals are selected from the 24 main array detection signals and output to the back-end processing. The antenna 2 uses 7 low-gain antennas to form an interferometer antenna array, and the number of signal processing channels of the back-end phase discrimination channel is 7, that is, the number of channels of the frequency conversion unit 1 and the frequency conversion unit 2 in the above is 7, and the number of AD channel samples of the detection unit and the phase discrimination unit is also 7.
[0029] Under normal circumstances (working condition 1), the 7 main array detection signals are output to the signal detection unit through the frequency conversion unit 1, and the 7 signals are sufficient to form an amplitude difference, and can form a preliminary amplitude ratio direction finding result. The 7 phase discrimination signals are output to the phase discrimination unit through the frequency conversion channel 2 to form an interferometer channel phase difference, and the phase difference is used for inverse calculation and combined with the amplitude ratio result to measure the azimuth angle of the signal.
[0030] Under abnormal conditions (working condition 2), it is assumed that one of the 7-phase channels in working condition 1 fails, for example, one of the frequency conversion channels in frequency conversion unit 2 fails, at this time, the phase difference of the phase detection channel lacks one channel of data, and the calculation of the interferometer direction finding result will be seriously affected. At this time, because the 7 processing channels corresponding to the main array signal are normal, the 7 main array detection signals are output to frequency conversion unit 2 through the routing switching network, the 7 phase detection signals are output to frequency conversion unit 1, and the original signal detection unit software is reconstructed as phase detection software, and the original phase detection unit is reconstructed as signal detection software. That is, the failed channel is placed in the detection channel, and the phase detection signal processing channel is ensured to be normal. For the main array detection signal, 7 channels are needed from 24 beams for instant selection for use in the back-end processing, because one channel of the back-end processing channel fails, so one channel of the corresponding signal cannot be processed. However, 7 channels are selected from 24 beams, and one beam is selected for multiplexing. In one selection condition, a certain space domain corresponds to the failed channel of the back-end, but in another selection mode, the space domain corresponding to the back-end may be a normal channel, so by reasonably constructing the selection relationship of the main array antenna beam, the failure of the back-end processing channel can minimize the influence on the direction finding result.
[0031] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. An interferometer direction finding system, characterized by, The interferometer direction finding system comprises: an antenna unit comprising a main array antenna and an interferometer antenna array, wherein the main array antenna is used for signal interception, parameter measurement and amplitude comparison direction finding, and the interferometer antenna array is used for signal phase difference extraction; a routing and switching network unit configured to route and switch signals from the main array antenna and the interferometer antenna array; the routing and switching process comprises: in a normal mode, a frequency conversion unit 1 processes the detection signals from the main array antenna, and a frequency conversion unit 2 processes the phase discrimination signals from the interferometer antenna array; in an abnormal mode, i.e. when a certain channel of the interferometer direction finding system backend fails to work normally, the frequency conversion unit 2 processes the detection signals from the main array antenna, and the frequency conversion unit 1 processes the phase discrimination signals from the interferometer antenna array, through the routing and switching of the routing and switching network unit; the frequency conversion unit comprises the frequency conversion unit 1 and the frequency conversion unit 2, which are configured to perform down-conversion processing on the signals transmitted by the routing and switching network unit, and convert the received radio frequency signals to intermediate frequency output for sampling and processing by a signal processing unit; the digital processing unit comprises a signal detection unit, a phase discrimination unit and a direction finding unit, the signal detection unit is configured to intercept and measure parameters of the main array antenna signals to form a detection channel pulse description word; the phase discrimination unit is configured to extract the phase difference of the interferometer antenna signals to form a phase discrimination channel phase difference result; the direction finding unit is configured to calculate the incoming direction of the signals by using the phase difference result of the phase discrimination channel and combining the amplitude comparison result of the detection channel.
2. The interferometer direction finding system of claim 1, wherein, The performance indicators of each frequency conversion channel of the frequency conversion unit 1 and the frequency conversion unit 2 are designed to be consistent.
3. The interferometer direction finding system of claim 2, wherein, The number of down-conversion channels in the frequency conversion unit 1 and the frequency conversion unit 2 is redundantly designed according to the maximum number of channels of the frequency conversion unit 1 or the frequency conversion unit 2.
4. The interferometer direction finding system of claim 1, wherein, The signal detection unit and the phase discrimination unit are designed to have consistent hardware, and the number of channels is redundantly designed to take the maximum number of detection channels and phase discrimination channels.
5. The interferometer direction finding system of claim 4, wherein, The signal detection unit is built-in with software capable of reconfiguring chips and links, and capable of performing software reconfiguration operation as needed; the phase discrimination unit is built-in with software capable of reconfiguring chips and links, and capable of performing software reconfiguration operation as needed.
6. The interferometer direction finding system of claim 1, wherein, The direction finding unit is designed to be capable of receiving data from the signal detection unit and the phase discrimination unit, and capable of automatically distinguishing the data sources for processing.