阅读说明：本技术 Sar收发链路相位抖动问题定位方法 (SAR transceiving link phase jitter problem positioning method ) 是由 矫远波 刘开雨 王宇 于 2019-08-01 设计创作，主要内容包括：本发明公开了一种SAR收发链路相位抖动问题定位方法,包括：获取第一收发链路对应的第一相位历程；所述第一收发链路是由调频信号源、可调衰减器和数据形成器连接组成的；判断所述第一相位历程是否存在相位抖动,得到第一判断结果；利用第一判断结果,确定所述调频信号源是否为故障单机。采用本发明的方案,能够定位导致SAR收发链路相位抖动问题的故障单机。(The invention discloses a method for positioning phase jitter problem of SAR (synthetic aperture radar) transceiving links, which comprises the following steps: acquiring a first phase process corresponding to a first transceiving link; the first transceiving link is formed by connecting a frequency modulation signal source, an adjustable attenuator and a data former; judging whether the first phase process has phase jitter or not to obtain a first judgment result; and determining whether the frequency modulation signal source is a single fault machine or not by using the first judgment result. By adopting the scheme of the invention, a fault single machine causing the phase jitter problem of the SAR transceiving link can be positioned.)

1. A Synthetic Aperture Radar (SAR) receiving and transmitting link phase jitter problem positioning method is characterized by comprising the following steps:

acquiring a first phase process corresponding to a first transceiving link; the first transceiving link is formed by connecting a frequency modulation signal source, an adjustable attenuator and a data former;

judging whether the first phase process has phase jitter or not to obtain a first judgment result;

and determining whether the frequency modulation signal source is a single fault machine or not by using the first judgment result.

2. The method of claim 1, wherein said determining whether said fm signal source is a faulty single-machine using said first determination comprises:

when the first judgment result represents that the first phase process has phase jitter, determining that the frequency modulation signal source is a single fault machine;

alternatively, the first and second electrodes may be,

and when the first judgment result represents that the first phase process has no phase jitter, determining that the frequency modulation signal source is not a single fault machine.

3. The method of claim 1, further comprising:

when the frequency modulation signal source is determined not to be a single fault machine, acquiring a second phase process corresponding to the second transceiving link; the second transceiving link is formed by connecting a first single machine in the first transceiving link; the first single machine is one of the following: radar receiver, microwave combination, pre-power amplifier;

judging whether the second phase process has phase jitter or not to obtain a second judgment result;

and determining whether the first single machine is a fault single machine or not by using a second judgment result.

4. The method according to claim 3, wherein said determining whether said first stand-alone is a faulty stand-alone by using the second determination result comprises:

when the second judgment result represents that phase jitter exists in the second phase process, determining that the first single machine is a fault single machine;

alternatively, the first and second electrodes may be,

and when the second judgment result represents that the second phase process has no phase jitter, determining that the first single machine is not a fault single machine.

5. The method of claim 3, further comprising:

when the first single machine is determined to be not a fault single machine, acquiring a third phase process corresponding to the third transceiving link; the third transceiving link is formed by connecting a second single machine in the second transceiving link; the second single machine is one of two single machines except the first single machine in the radar receiver, the microwave combination and the pre-power amplifier;

judging whether the third phase process has phase jitter or not to obtain a third judgment result;

and determining whether the second single machine is a fault single machine or not by using a third judgment result.

6. The method as claimed in claim 5, wherein said determining whether said second stand-alone is a faulty stand-alone by using a third determination result comprises:

when the third judgment result represents that the third phase process has phase jitter, determining the second single machine as a fault single machine;

alternatively, the first and second electrodes may be,

and when the third judgment result represents that the third phase process has no phase jitter, determining that the second single machine is not a fault single machine.

7. The method according to claim 5, wherein when it is determined that said second stand-alone is not a failed stand-alone, determining that a third stand-alone in a fourth transceiving link is a failed stand-alone; the third single machine is a single machine except the first single machine and the second single machine in the radar receiver, the microwave combination and the pre-power amplifier;

and the fourth transceiving link is formed by connecting the third single machine in the third transceiving link.

8. The method according to any one of claims 1 to 7, wherein it is determined that phase jitter is present in the respective phase history when the phase stability indicator of the respective phase history is determined to be greater than 0.5 °.

Technical Field

The invention relates to the field of Radar microwave remote sensing, in particular to a Synthetic Aperture Radar (SAR) receiving and transmitting link phase jitter problem positioning method.

Background

The double-base satellite-borne SAR is a technology which adopts formation satellites to form a base line and obtains surface elevation information through interference processing. The double stars fly repeatedly independently or in formation, and the ground surface deformation is obtained by using a three-rail method. Specifically, as shown in fig. 1, a satellite navigates through the same target area for multiple times, and observes the same target area for multiple times over a long time, and uses the phase information included in the obtained SAR complex image sequence to obtain the accurate deformation information of the earth's surface occurring within the observation time by using an advanced signal processing method. The interference imaging processing has the characteristic of being sensitive to phase information and requires good phase stability of radar emission signals.

The operating principle of the SAR transceiving link is shown in fig. 2, a linear frequency modulation signal output by a frequency modulation signal source is input to a microwave combination after the power of the linear frequency modulation signal is adjusted by a pre-power amplifier and an adjustable attenuator, the input signal is output to a data former by the microwave combination through a radar receiver, and the data former converts the input microwave signal into a digital signal, namely radar data; and carrying out digital pulse compression processing on the radar data to further obtain the phase process of the transceiving link.

The overall design of the radar enables each single machine in the SAR receiving and transmitting link to meet the phase stability requirement, and in the debugging, testing and acceptance testing process of each single machine device, as shown in fig. 3, a vector network analyzer can be used for testing the transmitting phase of a frequency modulation signal source, a pre-power amplifier and the receiving phase of a radar receiver in the receiving and transmitting link to obtain phase nonlinearity and phase stability indexes in a working frequency band; the microwave combination in the transceiving link is a passive single machine, and the influence of the internal circuit on the phase characteristics can be ignored. In the single machine debugging, testing and acceptance testing stage of the application, index testing is carried out on the phase characteristics of each single machine, and the actually measured phase stability index is qualified (namely, the requirement of SAR interference imaging is met), and is within 0.2 degrees. However, in the integrated test stage of the transmitting-receiving link, the phase process of the transmitting-receiving link has a jitter problem, the phase stability index is degraded to 2 degrees, and the requirement of SAR interference imaging is not met.

In addition, the integrated test method of the transceiving link in the related art cannot locate a single fault machine causing the problem of phase process jitter.

Disclosure of Invention

In view of this, the embodiment of the present invention provides a method for positioning phase jitter problem of SAR transceiving link.

The technical scheme of the embodiment of the invention is realized as follows:

the embodiment of the invention provides a method for positioning phase jitter problem of an SAR (synthetic aperture radar) transceiving link, which comprises the following steps:

acquiring a first phase process corresponding to a first transceiving link; the first transceiving link is formed by connecting a frequency modulation signal source, an adjustable attenuator and a data former;

judging whether the first phase process has phase jitter or not to obtain a first judgment result;

and determining whether the frequency modulation signal source is a single fault machine or not by using the first judgment result.

In the foregoing solution, the determining whether the frequency modulation signal source is a single fault machine by using the first determination result includes:

when the first judgment result represents that the first phase process has phase jitter, determining that the frequency modulation signal source is a single fault machine;

alternatively, the first and second electrodes may be,

and when the first judgment result represents that the first phase process has no phase jitter, determining that the frequency modulation signal source is not a single fault machine.

In the above scheme, the method further comprises:

when the frequency modulation signal source is determined not to be a single fault machine, acquiring a second phase process corresponding to the second transceiving link; the second transceiving link is formed by connecting a first single machine in the first transceiving link; the first single machine is one of the following: radar receiver, microwave combination, pre-power amplifier;

judging whether the second phase process has phase jitter or not to obtain a second judgment result;

and determining whether the first single machine is a fault single machine or not by using a second judgment result.

In the foregoing solution, the determining whether the first single machine is a faulty single machine by using the second determination result includes:

when the second judgment result represents that phase jitter exists in the second phase process, determining that the first single machine is a fault single machine;

alternatively, the first and second electrodes may be,

and when the second judgment result represents that the second phase process has no phase jitter, determining that the first single machine is not a fault single machine.

In the above scheme, the method further comprises:

when the first single machine is determined to be not a fault single machine, acquiring a third phase process corresponding to the third transceiving link; the third transceiving link is formed by connecting a second single machine in the second transceiving link; the second single machine is one of two single machines except the first single machine in the radar receiver, the microwave combination and the pre-power amplifier;

judging whether the third phase process has phase jitter or not to obtain a third judgment result;

and determining whether the second single machine is a fault single machine or not by using a third judgment result.

In the foregoing solution, the determining whether the second stand-alone is a faulty stand-alone by using the third determination result includes:

when the third judgment result represents that the third phase process has phase jitter, determining the second single machine as a fault single machine;

alternatively, the first and second electrodes may be,

and when the third judgment result represents that the third phase process has no phase jitter, determining that the second single machine is not a fault single machine.

In the above scheme, when it is determined that the second stand-alone machine is not a failed stand-alone machine, it is determined that a third stand-alone machine in a fourth transceiving link is a failed stand-alone machine; the third single machine is a single machine except the first single machine and the second single machine in the radar receiver, the microwave combination and the pre-power amplifier;

and the fourth transceiving link is formed by connecting the third single machine in the third transceiving link.

In the above scheme, when the phase stability index of the corresponding phase history is determined to be greater than 0.5 °, it is determined that the corresponding phase history has phase jitter.

According to the technical scheme provided by the embodiment of the invention, a first phase process corresponding to a first transceiving link is obtained; the first transceiving link is formed by connecting a frequency modulation signal source, an adjustable attenuator and a data former; judging whether the first phase process has phase jitter or not to obtain a first judgment result; and determining whether the frequency modulation signal source is a single fault machine or not by using the first judgment result. According to the scheme of the embodiment of the invention, whether the phase process of the transceiving link has jitter is judged, and whether the single machine connected in the transceiving link is a fault single machine is determined according to the judgment result, so that the fault single machine causing the phase jitter problem of the SAR transceiving link can be positioned.

Drawings

FIG. 1 is a schematic diagram of multi-pass differential interference imaging of a satellite of a space-borne SAR;

fig. 2 is a schematic diagram of the operating principle of the SAR transceiving link;

FIG. 3 is a schematic diagram of phase testing of each unit of the SAR transceiver link;

FIG. 4 is a flowchart illustrating a method for locating a phase jitter problem of an SAR transceiver link according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a troubleshooting connection of a frequency modulated signal source in an embodiment of the invention;

FIG. 6 is a schematic diagram of a troubleshooting connection of a radar receiver in accordance with an embodiment of the present invention;

FIG. 7 is a schematic diagram of a troubleshooting connection of a microwave assembly in accordance with an embodiment of the present invention;

FIG. 8 is a flowchart of a problem location process of a transceiving link according to an embodiment of the present invention.

Detailed Description

The technical solution of the present invention is further described in detail with reference to the drawings and the specific embodiments of the specification.

In various embodiments of the invention, the phase jitter problem is positioned by adopting an elimination method in an integrated test state of an SAR transceiving link; specifically, a transceiving link connected with a frequency modulation signal source, an adjustable attenuator and a data generator is configured, and whether the frequency modulation signal source is a single fault machine is determined by judging whether the phase process of the transceiving link has jitter. After determining that the frequency modulation signal source is not a single fault (i.e. the fault of the frequency modulation signal source is eliminated), the pre-power amplifier, the microwave combination and the radar receiver are respectively connected to the transceiving link in any sequence to determine whether the pre-power amplifier, the microwave combination and the radar receiver are in fault.

In various embodiments of the present invention, the threshold value of the phase stability indicator for determining whether the phase histories of the transceiving links are jittered is set to 0.5 °, that is, when the phase stability indicator of the phase histories of the transceiving links is greater than 0.5 °, it is determined that the phase histories of the transceiving links are jittered, and when the phase stability indicator of the phase histories of the transceiving links is less than or equal to 0.5 °, it is determined that the transceiving links are stable (i.e., there is no jitter). In practical application, the phase stability index threshold may be other values, and may be set by the user according to the requirement.

The embodiment of the invention provides a method for positioning the phase jitter problem of an SAR (synthetic aperture radar) transceiving link, which comprises the following steps as shown in figure 4:

step 401: acquiring a first phase process corresponding to a first transceiving link;

here, the first transceiving link is formed by connecting a frequency modulation signal source, an adjustable attenuator and a data former.

Step 402: and judging whether the first phase process has phase jitter or not to obtain a first judgment result.

Step 403: determining whether the frequency modulation signal source is a single fault machine or not by utilizing a first judgment result;

when the first judgment result represents that the first phase process has phase jitter, determining that the frequency modulation signal source is a single fault machine;

and when the first judgment result represents that the first phase process has no phase jitter, determining that the frequency modulation signal source is not a single fault machine.

In an embodiment, the method further comprises:

when the frequency modulation signal source is determined not to be a single fault machine, acquiring a second phase process corresponding to the second transceiving link; the second transceiving link is formed by connecting a first single machine in the first transceiving link; the first single machine is one of the following: radar receiver, microwave combination, pre-power amplifier;

judging whether the second phase process has phase jitter or not to obtain a second judgment result;

determining whether the first single machine is a fault single machine or not by using a second judgment result;

when the second judgment result represents that phase jitter exists in the second phase process, determining that the first single machine is a fault single machine;

and when the second judgment result represents that the second phase process has no phase jitter, determining that the first single machine is not a fault single machine.

In an embodiment, the method further comprises:

when the first single machine is determined to be not a fault single machine, acquiring a third phase process corresponding to the third transceiving link; the third transceiving link is formed by connecting a second single machine in the second transceiving link; the second single machine is one of two single machines except the first single machine in the radar receiver, the microwave combination and the pre-power amplifier;

judging whether the third phase process has phase jitter or not to obtain a third judgment result;

determining whether the second single machine is a fault single machine or not by using a third judgment result;

when the third judgment result represents that the third phase process has phase jitter, determining that the second single machine is a fault single machine;

and when the third judgment result represents that the third phase process has no phase jitter, determining that the second single machine is not a fault single machine.

In an embodiment, when it is determined that the second standalone is not a faulty standalone, it is determined that a third standalone in a fourth transceiving link is a faulty standalone;

the third single machine is a single machine except the first single machine and the second single machine in the radar receiver, the microwave combination and the pre-power amplifier;

and the fourth transceiving link is formed by connecting the third single machine in the third transceiving link.

The present invention will be described in further detail with reference to the following application examples.

In the SAR transceiving link phase jitter problem positioning method of the application embodiment, whether a frequency modulation signal source is a single fault machine is checked first; then checking whether the radar receiver is a single fault machine; then, whether the microwave combination is a single fault machine is checked; finally, according to the above checking result, directly determining whether the pre-power amplifier is a single fault machine; the method specifically comprises the following steps:

step 1: and judging whether the frequency modulation signal source is a single fault machine.

Specifically, as shown in fig. 5, a frequency modulation signal source, an adjustable attenuator, and a data former are connected to form a transceiving link, so that a chirp signal output by the frequency modulation signal source is output to the data former through the adjustable attenuator; the adjustable attenuator is used for attenuating the power of the linear frequency modulation signal, so that the signal output to the data former meets the power requirement of the input signal of the data former; the data former converts the input microwave signal into digital signal, and performs digital pulse compression processing on the digital signal to further obtain the phase history of the transceiving link.

Here, if the phase history is stable (i.e., no jitter is present), it can be determined that the fm signal source is not faulty; if the phase history has jitter (i.e. the phase stability index is greater than 0.5), it can be determined that the frequency modulation signal source is a fault single machine.

Step 2: and judging whether the radar receiver is a single fault machine.

Specifically, after determining that the fm signal source is not a single fault, as shown in fig. 6, connecting the radar receiver to the transceiving link in step 1, so that the chirp signal output by the fm signal source is output to the data former through the adjustable attenuator and the radar receiver; the adjustable attenuator is used for attenuating the power of the linear frequency modulation signal, so that the signal output to the radar receiver meets the power requirement of the input signal of the radar receiver; the data former converts the input microwave signal into digital signal, and performs digital pulse compression processing on the digital signal to further obtain the phase history of the transceiving link.

Here, if the phase history is stable (i.e., there is no jitter), it can be determined that the radar receiver is not faulty; if the phase history has jitter (i.e. the phase stability index is greater than 0.5), it can be determined that the radar receiver is a faulty single machine.

And step 3: and judging whether the microwave combination is a single fault machine.

Specifically, after it is determined that the radar receiver is not a single fault unit, as shown in fig. 7, the microwave combination is connected to the transceiving link in step 2, so that the chirp signal output by the fm signal source is output to the data generator through the adjustable attenuator, the microwave combination and the radar receiver; the adjustable attenuator is used for attenuating the power of the linear frequency modulation signal, so that the signal output to the microwave combination meets the power requirement of the microwave combination input signal; the data former converts the input microwave signal into digital signal, and performs digital pulse compression processing on the digital signal to further obtain the phase history of the transceiving link.

Here, if the phase history is stable (i.e., there is no jitter), it can be determined that the microwave combination is not faulty; if there is jitter in the phase history (i.e., the phase stability index is greater than 0.5 deg.), it can be determined that the microwave combination is a faulty single machine.

And 4, step 4: and (3) after determining that the frequency modulation signal source, the radar receiver and the microwave combination have no faults, connecting the pre-power amplifier to the transceiving link in the step (3), and when the transceiving link has a fault of phase jitter, directly determining that the pre-power amplifier is a single fault machine according to an elimination method because the faults of the frequency modulation signal source, the radar receiver and the microwave combination are eliminated.

The technical solution of the application embodiment is further described in detail with reference to the flow chart.

As shown in fig. 8, the method for locating a single fault by using the elimination method in the SAR transceiver link formed by connecting the frequency modulation signal source, the pre-power amplifier, the adjustable attenuator, the microwave combination, the radar receiver and the data former specifically includes the following steps:

step 801: the fm signal source, the adjustable attenuator, and the data former are connected to form a transceiver link, the phase history of the transceiver link is determined, and then step 802 is performed.

Step 802: judging whether the phase process is stable; if not, determining that the frequency modulation signal source fails; if yes, go to step 803.

Step 803: the radar receiver is connected to the transceiving link, the phase history of the transceiving link is determined, and then step 804 is performed.

Step 804: judging whether the phase process is stable; if not, determining that the radar receiver fails; if yes, go to step 805.

Step 805: the microwave combination is connected to the transceiving link, the phase history of the transceiving link is determined, and then step 806 is performed.

Step 806: judging whether the phase process is stable; if not, determining that the microwave combination fails; if yes, go to step 807.

Step 807: and according to the elimination method, the failure of the pre-power amplifier is positioned.

In practical application, a user can check the faults of the pre-power amplifier, the microwave combination and the radar receiver according to the needs of the user and any sequence.

The scheme provided by the application embodiment has the following advantages:

firstly, the fault location of the SAR system transceiving link phase jitter problem is solved.

Secondly, the operation method is simple and easy to implement, and is suitable for fault location of the phase jitter problem of the transceiving link of the airborne, vehicle-mounted and ground SAR systems; the method can also be used for preliminarily positioning the fault to a single-machine device for the satellite-borne SAR system, namely can also be applied to the phase problem positioning of single-base, double-base and multi-base satellite-borne SAR systems or the radar system of which the frequency modulation signal source outputs the non-linear frequency modulation signal, and has wide application range.

It should be noted that: the terms "first," "second," and the like in the embodiments of the present invention are used for distinguishing similar objects, and do not necessarily have to be used for describing a particular order or sequence.

In addition, the technical solutions described in the embodiments of the present invention may be arbitrarily combined without conflict.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.