CN112346094A - Rapid and high-precision radar course angle measurement method - Google Patents
Rapid and high-precision radar course angle measurement method Download PDFInfo
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- CN112346094A CN112346094A CN202011322742.8A CN202011322742A CN112346094A CN 112346094 A CN112346094 A CN 112346094A CN 202011322742 A CN202011322742 A CN 202011322742A CN 112346094 A CN112346094 A CN 112346094A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/35—Constructional details or hardware or software details of the signal processing chain
- G01S19/37—Hardware or software details of the signal processing chain
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/40—Means for monitoring or calibrating
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- Radar, Positioning & Navigation (AREA)
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- Computer Networks & Wireless Communication (AREA)
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Abstract
The invention relates to a rapid and high-precision radar course angle measuring method, which belongs to the technical field of navigation and control and comprises the following steps: s1, the receiver receives satellite ephemeris information through an antenna to perform initial positioning; s2, the receiver sends the satellite ephemeris information received every second to the single chip microcomputer; s3, performing a fine sweeping process; s4, under the condition that the first fine sweeping is effective, carrying out a second fine sweeping; and S5, determining the radar heading angle. The antenna zero position is adjustable, the position setting is flexible, and the course angle output time can be further shortened by the electric scanning function; the course angle is calculated based on the original ephemeris message forwarded by the singlechip autonomous resolving receiver, and the calculation precision is controllable.
Description
Technical Field
The invention relates to a rapid and high-precision radar course angle measurement method, which is used for course angle measurement of an outdoor radar and belongs to the technical field of navigation and control.
Background
When the radar identifies a target, the course and distance information of the target need to be acquired in real time and displayed on a map. Since the range of the radar can reach several tens of kilometers, the deviation of the initial course angle can bring about a deviation of several hundred meters in the dimension of the target range. Currently, three heading angle measurement schemes are commonly used, namely a magnetic compass; secondly, a gyro north seeker; and thirdly, a double-antenna GPS attitude measurer.
Magnetic compasses measure the spatial attitude angle using the inherent directivity of the geomagnetic field. The magnetic compass is greatly influenced by surrounding steel structures and electrical equipment. The gyro north finder is an inertial measurement system for measuring the projection direction of the angular rate of rotation of the earth on the local horizontal plane by using the gyro principle. Besides being limited by high latitude, its north-seeking measurement is not affected by weather, day and night time, geomagnetic field and field communication condition, but is expensive. Based on dual GPS baseline measurement, two or more antennas are adopted to form a baseline vector, GPS carrier measurement data is adopted to determine the integer ambiguity so as to solve the attitude angle, the measurement accuracy of the attitude angle is limited by the length of the baseline, and the size of the attitude angle cannot be miniaturized.
Disclosure of Invention
The technical problem solved by the invention is as follows: the method overcomes the defects of the prior art, provides a rapid and high-precision radar course angle measuring method, realizes rapid actual combat launching of the ship-based missile, and effectively improves the actual combat capability and combat efficiency of the ship-based weapon.
The technical scheme of the invention is as follows:
a rapid and high-precision radar course angle measurement method comprises the following specific steps:
s1, the receiver receives satellite ephemeris information through an antenna to perform initial positioning;
s2, the receiver sends satellite ephemeris information received once per second to a single chip microcomputer, a motor performs coarse scanning for one week at 15-30 degrees/second, the single chip microcomputer records the numbers of all local visible satellites and corresponding carrier-to-noise ratios, satellites with carrier-to-noise ratios above 65 are recorded as strong signal satellites sat 1-satn, the maximum value of the carrier-to-noise ratio of each strong signal satellite max 1-maxn and the angle range of the carrier-to-noise ratio above 65 are recorded as angle1-angle 2;
s3, performing a fine sweep: after the motor rotates to angle1, starting a first round of fine scanning at 2-5 degrees/second, judging by using the mean value of data acquired at least 4 times, if the current carrier-to-noise ratio mean value sat1 carrier-to-noise ratio max1 is decreased by 15, switching to single data acquisition judgment, recording the angle range of 20 decrease of the single data value max1 as angle 3-angle 4, then switching to the mean value of the data acquired at least 4 times for judgment, continuing the rotation of the stepping motor, starting the rise of the sat1 carrier-to-noise ratio at the moment, reaching a strong signal threshold 65, marking the whole process as valid, and if the strong signal threshold 65 cannot be reached, marking the process as invalid, and starting the fine scanning on sat 2;
and S4, when the first fine sweeping is effective, carrying out a second fine sweeping: the second round of fine scanning ranges from angle3 to angle4, the precision control of the stepping motor is 0.2-0.6 degrees/second, data acquired every 4 times is recorded as 1 group, the angle of the data acquired every 4 times is recorded as the group angle, the mean value of the carrier-to-noise ratios acquired every 4 times is recorded as the group carrier-to-noise ratio, the motor angle5 corresponding to the minimum value of the carrier-to-noise ratio occurring in sat1 in the scanning process is recorded, then the motor is turned to angle5 again, and the heading angle B of the satellite at the moment is calculated through satellite ephemeris analysis;
and S5, determining a radar heading angle C as B-A-angle5, wherein the satellite heading angle B is a real direction taking the geographical north direction as a reference, the angle5 is an angle which the measuring equipment rotates relative to the zero point of the motor, and A is an included angle between the antenna directional diagram zero point plane and the radar heading.
Furthermore, the antenna directional diagram has steep zero points, and the angle range of the zero depth change of 30 dB-40 dB is within 1 degree, so that the accuracy of real-time data calculation is ensured.
Further, if the result of the first round of fine scanning is invalid, the satellite is replaced to carry out the first round of fine scanning again.
Furthermore, the receiver can forward the satellite real-time ephemeris information, and data analysis is performed by using the satellite ephemeris information broadcasted every second by the satellite, so as to obtain the Doppler orbit parameters of the satellite and further calculate the course angle.
Furthermore, the rear end of the antenna is matched with an active phase shifter to carry out beam zero distribution design, and the position corresponding to the antenna zero and the device to be tested form a fixed angle difference.
Further, the satellite ephemeris information includes satellite position, local latitude and longitude, and current time information.
Compared with the prior art, the invention has the beneficial effects that:
(1) the antenna zero position is adjustable, the position setting is flexible, and the course angle output time can be further shortened by the electric scanning function;
(2) the course angle is calculated based on the original ephemeris message forwarded by the singlechip autonomous resolving receiver, and the calculation precision is controllable;
(3) the invention designs a course angle zero point locking method based on combination of motor rotation coarse and fine sweeps, which omits the information acquisition process of satellite almanac prediction and has a simpler scheme;
(4) the antenna provided by the invention is additionally provided with the coupling branch and the guiding branch, so that the electric size of the antenna is reduced, the reactance component of the antenna is reduced, and the radiation efficiency of the antenna is improved;
(5) the method can be used for calibration of outdoor equipment, the course angle resolving time is short, and the accuracy is better than 1 degree.
Drawings
FIG. 1 is a schematic diagram of the measurement of the radar course angle according to the present invention;
FIG. 2 is a flow chart of a course angle solution algorithm of the present invention.
Detailed Description
The invention is further illustrated by the following examples.
And selecting a receiver with the function of transmitting the real-time ephemeris information of the satellite, carrying out data analysis by using the ephemeris message information broadcasted every second by the satellite, acquiring the Doppler orbit parameter of the satellite, further calculating the course angle, and reserving the last two digits of the decimal point of the angle calculation value.
The antenna feed part is designed with an array antenna with a specific zero point direction, the rear end of the antenna is matched with an active phase shifter to carry out beam zero point distribution design, and the position corresponding to the antenna zero point and a device to be tested form a fixed angle difference.
The radio frequency front end with the two-stage amplifier is designed, carrier-to-noise ratio compensation is carried out on a received signal, the lower-layer receiver is connected through a radio frequency cable, and a lower-layer power supply circuit supplies power to the radio frequency front end through a terminal.
And designing a set of full-load noise value discrimination algorithm to lock the zero point of the measured data. And (4) eliminating jump data and satellite loss situation through multiple mean judgment and value judgment algorithms to obtain high-precision course angle output.
And a judgment method combining rough scanning and fine scanning is carried out by adopting a high-precision control motor. Firstly, the motor drives the antenna and the receiver to rotate for a circle quickly, and the current carrier-to-noise ratio of all visible satellites is obtained. After screening, determining a roughly selected area, judging a full-load noise value judgment algorithm, planning a finely-scanned area, judging again, and locking a zero point corresponding position after three times of judgment.
The accuracy of the course angle is determined by four aspects, namely satellite ephemeris resolving accuracy, antenna zero corresponding angle, threshold setting of a full-load noise value discrimination algorithm, and control accuracy of a high-precision motor.
Examples
And selecting a receiver with a satellite ephemeris forwarding function, and receiving and analyzing the ephemeris of the Beidou or the GPS. As shown in fig. 1, course angle calculation is performed by referring to different calculation methods of the system, and two effective digits behind a decimal point of a calculation value of the course angle are reserved.
The zero depth of a designed miniaturized antenna directional diagram is more than 30dB, an active phase shifter is arranged at the rear end of the antenna, the pointing direction of the antenna zero point can be controlled, the included angle A between the projection line of the plane corresponding to the antenna zero point on the ground plane and the fixed line and the satellite north deflection angle B obtained through calculation jointly determine the course angle C of the actual pointing direction of the device.
The radio frequency front end comprises a filter with frequency covering Beidou B1L and an L1 frequency band of a GPS and a two-stage low noise amplifier. The cascade gain is more than 20 dB. The power supply of the radio frequency circuit is provided by the lower layer circuit board, and the radio frequency output is connected to the lower layer interface by the radio frequency interface of the upper layer circuit board.
The lower circuit comprises a motor controller, a single chip microcomputer, a satellite receiver and a power supply system.
The dynamic course angle calculation algorithm is specifically realized in such a way that after the device is powered on, the receiver receives satellite ephemeris once per second and sends the satellite ephemeris to the single chip microcomputer, the motor performs coarse sweeping for one circle at 20 degrees/second, the single chip microcomputer records the numbers of all local visible satellites and corresponding carrier-to-noise ratios, the satellites with the carrier-to-noise ratios above 65 are recorded as strong signal satellites sat 1-satn, the maximum value of the carrier-to-noise ratio of each strong signal satellite max 1-maxn and the angle range of the carrier-to-noise ratio above 65, namely angle1-angle2, are recorded.
Then, a fine scanning process is started, as shown in fig. 1, for example, sat1 (both beidou and GPS, and numbering is performed in the order of actually resolving satellites meeting the conditions), after the motor rotates to angle1, a first round of fine scanning is started at2 degrees/second, judgment is performed by using the mean value of 4 times of acquired data, if the current carrier-to-noise ratio mean value sat1 is decreased by 15 times by the carrier-to-noise ratio max1, single-time data acquisition judgment is switched, the angle range of 20 times of decrease of the single-time data value from max1 is recorded as angle3 to angle4, then the judgment is switched to the mean value of 4 times of acquired data for judgment, the stepping motor continues to rotate, at this time, the carrier-to-noise ratio sat1 starts to increase, the strong signal threshold 65 is reached, the whole process flag is valid, and if the strong signal threshold 65 cannot be reached, the process is marked as invalid, and fine scanning is started on sat 2.
And under the condition that the first fine sweeping is effective, carrying out second fine sweeping. The second round of fine scanning ranges from angle3 to angle4, the precision of the stepping motor is controlled to be 0.2 degrees/second, data collected every 4 times is recorded as 1 group, the angle of the data collected at the 4 th time is recorded as the group angle, the mean value of carrier-to-noise ratios collected at the 4 times is recorded as the group carrier-to-noise ratio, and the motor angle5 corresponding to the minimum value of the carrier-to-noise ratio of sat1 in the scanning process is recorded. Then the motor is turned to angle5 again, and satellite ephemeris analysis is carried out to calculate the heading angle B of the satellite at the moment.
An active phase shifter determines an included angle A between a zero plane of an antenna directional diagram and the radar course; the zero point of the motor points to be consistent with the heading angle of the radar, the heading angle B of the satellite is a real direction taking the geographical north direction as a reference, and angle5 is the angle of the measuring equipment rotating relative to the zero point of the motor, so that the heading angle of the radar is C-B-A-angle 5.
The antenna directional diagram in the embodiment should have a steep zero point, and the angle range of the zero depth change of 30 dB-40 dB should be within 1 degree, so as to ensure the accuracy of real-time data calculation.
The average judgment in the example cannot be replaced by single-value judgment, and if the first round of fine scanning is invalid, the satellite should be replaced to carry out the first round of fine scanning again.
The course angle measuring method is applied to the radar north correction and target tracking processes, is not interfered by the surrounding electromagnetic environment, and can control the course angle precision according to the actual requirement.
The antenna zero position is adjustable, the position setting is flexible, and the course angle output time can be further shortened by the electric scanning function;
the course angle is calculated based on the original ephemeris message forwarded by the singlechip autonomous resolving receiver, and the calculation precision is controllable;
the invention designs a course angle zero point locking method based on combination of motor rotation coarse and fine sweeps, which omits the information acquisition process of satellite almanac prediction and has a simpler scheme;
the antenna provided by the invention is additionally provided with the coupling branch and the guiding branch, so that the electric size of the antenna is reduced, the reactance component of the antenna is reduced, and the radiation efficiency of the antenna is improved.
Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make variations and modifications of the present invention without departing from the spirit and scope of the present invention by using the methods and technical contents disclosed above.
Claims (6)
1. A rapid and high-precision radar course angle measurement method is characterized by comprising the following specific steps:
s1, the receiver receives satellite ephemeris information through an antenna to perform initial positioning;
s2, the receiver sends satellite ephemeris information received once per second to a single chip microcomputer, a motor performs coarse scanning for one week at 15-30 degrees/second, the single chip microcomputer records the numbers of all local visible satellites and corresponding carrier-to-noise ratios, satellites with carrier-to-noise ratios above 65 are recorded as strong signal satellites sat 1-satn, the maximum value of the carrier-to-noise ratio of each strong signal satellite max 1-maxn and the angle range of the carrier-to-noise ratio above 65 are recorded as angle1-angle 2;
s3, performing a fine sweep: after the motor rotates to angle1, starting a first round of fine scanning at 2-5 degrees/second, judging by using the mean value of data acquired at least 4 times, if the current carrier-to-noise ratio mean value sat1 carrier-to-noise ratio max1 is decreased by 15, switching to single data acquisition judgment, recording the angle range of 20 decrease of the single data value max1 as angle 3-angle 4, then switching to the mean value of the data acquired at least 4 times for judgment, continuing the rotation of the stepping motor, starting the rise of the sat1 carrier-to-noise ratio at the moment, reaching a strong signal threshold 65, marking the whole process as valid, and if the strong signal threshold 65 cannot be reached, marking the process as invalid, and starting the fine scanning on sat 2;
and S4, when the first fine sweeping is effective, carrying out a second fine sweeping: the second round of fine scanning ranges from angle3 to angle4, the precision control of the stepping motor is 0.2-0.6 degrees/second, data acquired every 4 times is recorded as 1 group, the angle of the data acquired every 4 times is recorded as the group angle, the mean value of the carrier-to-noise ratios acquired every 4 times is recorded as the group carrier-to-noise ratio, the motor angle5 corresponding to the minimum value of the carrier-to-noise ratio occurring in sat1 in the scanning process is recorded, then the motor is turned to angle5 again, and the heading angle B of the satellite at the moment is calculated through satellite ephemeris analysis;
and S5, determining a radar heading angle C as B-A-angle5, wherein the satellite heading angle B is a real direction taking the geographical north direction as a reference, the angle5 is an angle which the measuring equipment rotates relative to the zero point of the motor, and A is an included angle between the antenna directional diagram zero point plane and the radar heading.
2. The method for rapidly and accurately measuring the heading angle of the radar as claimed in claim 1, wherein an antenna directional diagram has a steep zero point, and the zero point is 30dB to 40dB deep and has an angle range within 1 degree so as to ensure the accuracy of real-time data calculation.
3. A fast and high-precision radar heading angle measuring method as claimed in claim 1, wherein if the first fine sweep is invalid, the satellite is replaced to perform the first fine sweep again.
4. The method as claimed in claim 1, wherein the receiver can forward real-time ephemeris information of the satellite, and perform data analysis using ephemeris information of the satellite broadcast every second to obtain doppler orbit parameters of the satellite, so as to further perform calculation of the course angle.
5. The method as claimed in claim 1, wherein the back end of the antenna is matched with an active phase shifter to design the distribution of the beam zero point, and the position corresponding to the antenna zero point has a fixed angle difference with the device to be measured.
6. The method as claimed in claim 1, wherein the satellite ephemeris information includes satellite position, local latitude and longitude, and current time information.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115776345A (en) * | 2021-09-08 | 2023-03-10 | 北京三快在线科技有限公司 | Interference measurement method and device, storage medium and electronic equipment |
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| CN115776345B (en) * | 2021-09-08 | 2024-02-23 | 北京三快在线科技有限公司 | Interference measurement method and device, storage medium and electronic equipment |
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