An interferometer internal correction method based on anomaly monitoring

Abstract

The present invention discloses an interferometer internal calibration method based on abnormal monitoring, comprising the following steps: S1, preheating the device for a period of time before the device leaves the factory, performing multiple internal calibration operations after preheating, and obtaining the internal calibration table Mi corresponding to the temperature monitoring chip at different temperatures; S2, performing the first internal calibration operation before the device leaves the factory and works normally, obtaining and applying the internal calibration table A, and recording the temperature Ti of the temperature monitoring chip at this time; S3, triggering a new internal calibration operation under certain conditions; S4, the new internal calibration operation is: after performing internal calibration on several randomly selected frequency points, comparing the internal calibration result C with the internal calibration table A and the internal calibration table Mi corresponding to the temperature Ti for the corresponding frequency point calibration data, modifying and applying the internal calibration table A according to the comparison result; S5, repeating steps S3 to S4 until the device ends operation. The present invention greatly improves the adaptability of the system to temperature changes.

Description

Technical Field

[0001] The invention belongs to the technical field of radio direction finding, and in particular relates to an interferometer internal correction method based on abnormality monitoring. Background Art

[0002] Interferometer system is widely used in the field of direction finding due to its simple composition and high direction finding accuracy. As the simplest direction finding method, it is also the basis of other direction finding methods.

[0003] The main sources of error in this direction-finding method include the nonlinear effect of the radome, antenna installation errors, the antenna's response to waves from different directions, and the deterioration of the internal calibration table due to module temperature changes. The effect of the radome can be reduced by improving the design of the radome and calibrating it together with the antenna; the antenna installation error can also be reduced by improving the installation accuracy; the antenna's response to waves from different directions can be solved through all-round external calibration. However, the deterioration of the internal calibration table is caused by device temperature changes, device nonlinearity, etc., and it takes a great price to solve its adverse effects.

[0004] Current electronic equipment often ignores the impact of this factor, and only performs an internal calibration before the equipment is put into use or before the equipment works normally, and assumes that the calibration table will not change in the following period of time. However, as the operating temperature rises, the actual value of the internal calibration table may change, resulting in a deterioration in the direction finding accuracy in field experiments.

[0005] Adding internal calibration during normal working hours can effectively deal with the above problems. However, internal calibration takes a certain amount of time, and the normal operation of the system will be suspended during the internal calibration process, which will inevitably cause a decrease in the interception probability and affect the customer experience.

[0006] Therefore, a new internal correction method is needed to improve the environmental and signal adaptability of the interferometer system, which is of great significance to improving the direction finding accuracy. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention provides an interferometer internal calibration method based on abnormality monitoring to solve the internal calibration problem of the interferometer system in actual work.

[0008] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is: an interferometer internal correction method based on abnormality monitoring, comprising the following steps:

[0009] S1. Before the equipment leaves the factory, the equipment is preheated for a period of time. After preheating, multiple internal calibration operations are performed to obtain the internal calibration table Mi corresponding to different temperatures Ti of the temperature monitoring chip;

[0010] S2. After the device leaves the factory and before normal operation, the first internal calibration operation is performed to obtain and apply the internal calibration table A, and the temperature Ti of the temperature monitoring chip at this time is recorded;

[0011] S3, triggering a new internal correction under certain conditions;

[0012] S4, new internal calibration: after performing internal calibration on several randomly selected frequency points, compare the internal calibration result C with the internal calibration table A and the internal calibration table Mi corresponding to the temperature Ti for the corresponding frequency calibration data, and modify the internal calibration table A according to the comparison result and apply it;

[0013] S5. Repeat steps S3 to S4 until the device stops running.

[0014] Further: in the extension device, a temperature monitoring chip is provided in the AD acquisition module / correction source module / module exterior.

[0015] Further: the condition in step S3 is:

[0016] During normal operation, the main control module reads the temperature of the temperature monitoring chip in real time, and starts an internal correction every time the temperature change exceeds a certain temperature threshold;

[0017] Or during normal operation, internal calibration can be started at regular intervals.

[0018] Furthermore: the temperature threshold is 1°C, the time interval is 10 minutes, and the values ​​can be adjusted according to actual conditions.

[0019] Furthermore: the internal correction is to extract some frequency points for internal correction, and the extraction method is random extraction within the working frequency band to ensure that the probability of each frequency point being extracted is the same, and at the same time ensure that all working frequency points can be covered after multiple internal correction frequency point extractions.

[0020] Furthermore: the number of extracted frequency points is 2 to 3, and the number of frequency points can be adjusted to other values ​​according to the real-time requirements of the device.

[0021] Further: the comparison method is specifically:

[0022] When (CA)>Th and (C-Mi)>Th, Th is the significance threshold, and a complete internal correction is restarted to obtain the internal correction table B, which is used to replace the internal correction table A;

[0023] When (CA) <= Th, the internal correction table A remains unchanged;

[0024] When (CA)>Th and (C-Mi)<=Th, a complete internal correction is no longer performed, and the internal correction table Mi corresponding to the temperature of the temperature monitoring chip is directly used instead of the internal correction table A.

[0025] Furthermore: the complete internal calibration is to perform an internal calibration on each frequency point within all working frequency bands.

[0026] The beneficial effects of the present invention are:

[0027] 1. The present invention starts the second internal calibration according to the temperature change situation obtained in real time by the main control module or at a certain time interval, which can effectively reduce the number of times the internal calibration is started and maximize the normal working time of the system.

[0028] 2. The new internal correction mentioned in S3 of the present invention adopts a method of correcting only a few frequency points, which can effectively improve the correction speed, speed up the correction process, and avoid affecting normal work as much as possible.

[0029] 3. The new internal calibration mentioned in S3 of the present invention compares the calibration result C with the original calibration table A and the pre-calibration table Mi corresponding to the temperature Ti, and uses the significance of the difference as the basis for whether to retain the calibration table A, replace the calibration table A with Mi, or start a complete internal calibration again. It can start a new complete internal calibration in time when the actual internal calibration value changes, and at the same time, it can minimize the number of complete internal calibrations, reduce the calibration workload, and greatly improve the system's adaptability to temperature changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The schematic diagram of the interferometer internal correction DETAILED DESCRIPTION

[0031] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0032] like Figure 1 As shown, the device is working in normal working state. There is a temperature monitoring chip in the acquisition module. If the module does not have this chip, the temperature of the FPGA in the module or the temperature of other temperature monitoring chips in other modules or extension devices can be used as an approximate substitute.

[0033] An interferometer internal correction method based on abnormality monitoring comprises the following steps:

[0034] S1. Before the equipment leaves the factory, the equipment is preheated for a period of time, and after preheating, multiple internal calibration operations are performed to obtain the internal calibration table Mi corresponding to different temperatures of the temperature monitoring chip;

[0035] S2. After the device leaves the factory and before normal operation, the first internal calibration operation is performed to obtain and apply the internal calibration table A, and the temperature Ti of the temperature monitoring chip at this time is recorded;

[0036] S3. Trigger a new internal correction operation under certain conditions; the condition is to meet any of the following conditions.

[0037] 1) During normal operation, the main control module reads the temperature of the temperature monitoring chip in real time. When the temperature changes by more than a certain threshold, such as every increase or decrease of 1°C (the value is determined according to the actual situation), a new internal calibration is started.

[0038] 2) During normal operation, a new internal calibration is started at a certain time interval, such as every 10 minutes (the value is determined based on actual conditions).

[0039] S4, new internal calibration: after performing internal calibration on several randomly selected frequency points, compare the internal calibration result C with the internal calibration table A and the internal calibration table Mi corresponding to the temperature Ti for the corresponding frequency calibration data, and modify the internal calibration table A according to the comparison result and apply it;

[0040] The new internal correction here is to extract some frequency points (for example, 2 to 3) for internal correction.

[0041] The extraction method is to randomly extract within the working frequency band to ensure that the probability of each frequency point being extracted is the same. At the same time, it is ensured that all working frequency points can be covered after multiple internal correction frequency point extractions.

[0042] If there are large phase differences, that is, (CA)>Th and (C-Mi)>Th (Th is the significance threshold, which is determined according to the actual situation and is temporarily set at 1°), it means that the current internal correction table has a large difference from the initial internal correction table A and the pre-internal correction table Mi, and a complete internal correction should be restarted to obtain the internal correction table B to replace the original correction table A.

[0043] If the difference between C and A is very small, that is, (CA) <= Th, it is considered that the actual correction table has not changed significantly. At this time, the original correction table A is still applicable to the current situation, and A remains unchanged.

[0044] If the difference between C and A is large, that is, (CA)>Th, but the difference between C and Mi is small, that is, (C-Mi)<=Th, then it is considered that the internal correction table A no longer meets the requirements, but the pre-correction table Mi can still adapt to the current temperature changes, then no complete internal correction is performed, and Mi corresponding to the temperature of the temperature monitoring chip is directly used to replace the correction table A.

[0045] Complete internal calibration is to perform an internal calibration on every frequency point within all working frequency bands.

[0046] S5. Repeat steps S3 to S4 until the device stops running.

[0047] By monitoring the temperature change of the temperature monitoring chip or setting a certain time interval to start a new internal calibration, and the new internal calibration adopts a calibration method of several frequency points, the calibration time can be significantly reduced, and the normal working time of the system can be guaranteed to the greatest extent. By comparing the calibration value C of several frequency points of the new internal calibration with the original calibration table A and the pre-calibration table Mi, the abnormality of the calibration can be quickly discovered, so as to decide whether to start a complete internal calibration to update the internal calibration table, so that the interferometer direction finding can be more adaptable to changes in factors such as temperature, which is of great significance to improving the performance of the equipment.

Claims

1. An interferometer internal correction method based on abnormality monitoring, characterized in that: The following steps are involved: S1. Before the equipment leaves the factory, the equipment is preheated for a period of time, and after preheating, multiple internal calibration operations are performed to obtain the internal calibration table Mi corresponding to different temperatures of the temperature monitoring chip; S2. After the device leaves the factory and before normal operation, the first internal calibration operation is performed to obtain and apply the internal calibration table A, and the temperature Ti of the temperature monitoring chip at this time is recorded; S3, triggering a new internal correction operation under certain conditions; S4, the new internal correction operation is: after performing internal correction on several randomly selected frequency points, the internal correction result C is compared with the internal correction table A and the internal correction table Mi corresponding to the temperature monitoring chip temperature Ti for the corresponding frequency point correction data, and the internal correction table A is modified and applied according to the comparison result; S5, repeat steps S3 to S4 until the device stops running; The internal correction is to extract some frequency points for internal correction, and the extraction method is to randomly extract within the working frequency band to ensure that the probability of each frequency point being extracted is the same, and at the same time ensure that all working frequency points can be covered after multiple internal correction extractions; The comparison method is specifically as follows: When |CA|>Th and |C-Mi|>Th, Th is the significance threshold, then a complete internal correction should be restarted to obtain the internal correction table B, which is used to replace the original internal correction table A; When |CA|<=Th, the internal correction table A remains unchanged; When |CA|>Th and |C-Mi|<=Th, no complete internal correction is performed, and the internal correction table Mi corresponding to the temperature Ti of the temperature monitoring chip is directly used instead of the internal correction table A; The complete internal calibration is to perform an internal calibration on each frequency point within all working frequency bands.

2. The interferometer internal correction method based on abnormality monitoring according to claim 1, characterized in that: In the extension device of the interferometer, a temperature monitoring chip is provided in the AD acquisition module, the correction source module or outside the module.

3. The interferometer internal correction method based on abnormality monitoring according to claim 1, characterized in that: The conditions in step S3 are: During normal operation, the main control module reads the temperature of the temperature monitoring chip in real time, and starts an internal correction every time the temperature change exceeds a certain temperature threshold; Or during normal operation, internal calibration can be started at regular intervals.

4. The interferometer internal correction method based on abnormality monitoring according to claim 3, characterized in that: The temperature threshold and time interval can be adjusted according to actual conditions.

5. The interferometer internal correction method based on abnormality monitoring according to claim 4, characterized in that: The temperature threshold is 1° C., and the time interval is 10 minutes.

6. The interferometer internal correction method based on abnormality monitoring according to claim 5, characterized in that: The number of extracted frequency points can be adjusted according to the real-time requirements of the device.

7. The interferometer internal correction method based on abnormality monitoring according to claim 6, characterized in that: The number of extracted frequency points is 2~3.

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