阅读说明：本技术 一种高精度干涉仪 (High-precision interferometer ) 是由 孙松斌 于 2021-10-08 设计创作，主要内容包括：本发明公开了一种高精度干涉仪,其包括天线阵、射频通道和基带处理模块；天线阵连接射频通道,射频通道连接基带处理模块,天线阵包括六个天线,其中四条天线形成两条相互垂直的长基线,另外两条天线与四条天线中的两条结合,形成两条相互垂直的短基线；射频通道有三个,分别通过切换开关连通对应的天线,经由基带处理模块计算入射角度,用于实时测量入射波入射角度。本发明通过增加天线阵的方法,实现低成本的条件下,提高测角精度；通过增加一条与原基线垂直的基线,保证入射波从任何方位入射,总有一条基线的垂线与入射波的夹角小于或等于45度；通过通道开关切换的方式,仅增加天线,不增加射频通道,控制成本。(The invention discloses a high-precision interferometer, which comprises an antenna array, a radio frequency channel and a baseband processing module, wherein the antenna array is connected with the radio frequency channel; the antenna array is connected with a radio frequency channel, the radio frequency channel is connected with the baseband processing module, the antenna array comprises six antennas, wherein four antennas form two mutually vertical long baselines, and the other two antennas are combined with two of the four antennas to form two mutually vertical short baselines; the three radio frequency channels are respectively communicated with the corresponding antennas through the selector switch, and the incident angle is calculated through the baseband processing module and is used for measuring the incident angle of the incident wave in real time. The invention improves the angle measurement precision by adding the antenna array method under the condition of low cost; by adding a base line perpendicular to the original base line, incident waves are ensured to be incident from any direction, and the included angle between the perpendicular line with the base line and the incident waves is always less than or equal to 45 degrees; through the way of channel switch switching, only increase the antenna, do not increase the radio frequency channel, control cost.)

1. A high-precision interferometer is characterized by comprising an antenna array, a radio frequency channel and a baseband processing module; the antenna array is connected with a radio frequency channel, the radio frequency channel is connected with the baseband processing module, the antenna array comprises six antennas, wherein four antennas form two mutually vertical long baselines, and the other two antennas are combined with two of the four antennas to form two mutually vertical short baselines; the three radio frequency channels are respectively communicated with the corresponding antennas through the selector switch, and the incident angle is calculated through the baseband processing module and is used for measuring the incident angle of the incident wave in real time.

2. The interferometer of claim 1, wherein six antennas of the antenna array are respectively denoted as antenna a1, antenna a2, antenna A3, antenna B1, antenna B2 and antenna B3, wherein antenna a1 and antenna A3 form a long baseline, antenna B1 and antenna B3 form a second long baseline, and the two long baselines are perpendicular to each other; antenna a1 and antenna a2 form a short baseline, and antenna B1 and antenna B2 form a second short baseline, which are perpendicular to each other.

3. The high accuracy interferometer of claim 2, wherein the antenna A2 is disposed between antenna A1 and antenna A3.

4. The high accuracy interferometer of claim 3, wherein antenna B2 is disposed between antenna B1 and antenna B3.

5. The interferometer of claim 4, wherein the two long baselines are equal or unequal in length.

6. The interferometer of claim 5, wherein the length of the two long baselines is limited by the interferometer mounting platform dimensions, and the length of each long baseline is not less than the corresponding mounting platform length at the mounting location of the long baseline.

7. The interferometer of claim 6, wherein the two short baselines are equal or unequal in length.

8. The interferometer of claim 7, wherein the lengths of the two short baselines are limited by the incoming wavelength and are each less than half the incoming wavelength.

9. The method for measuring the incident wave incident angle in real time based on the high-precision interferometer of claim 8 is characterized by comprising the following steps:

firstly, controlling a change-over switch to enable an antenna A1 to be connected with a radio frequency channel 1, an antenna A2 to be connected with a radio frequency channel 2, and an antenna A3 to be connected with a radio frequency channel 3, and calculating the incident angle of incident waves

Second, judging the incident angle of the incident waveWhether the angle is greater than 45 degrees or not, and if the angle is not greater than 45 degrees, the angle is used as a real measuring angle of the incident wave; if the angle is more than 45 degrees, the change-over switch is controlled to enable the sun to be closeThe line B1 is connected with the radio frequency channel 1, the antenna B2 is connected with the radio frequency channel 2, the antenna B3 is connected with the radio frequency channel 3, and the incident wave incident angle beta is calculated;

thirdly, judging whether the incident angle beta of the incident wave is greater than 45 degrees or not, and if not, taking the angle as the real measurement angle of the incident wave; if the angle is larger than 45 degrees, the change-over switch is controlled to connect the antenna A1 with the radio frequency channel 1, the antenna A2 with the radio frequency channel 2, the antenna A3 with the radio frequency channel 3 and merge the incident angle of the radio wave

And fourthly, repeating the second step and the third step to measure the incident angle of the incident wave in real time.

10. Use of a high-precision interferometer according to any of claims 1-8 in the field of radio direction finding.

Technical Field

The invention belongs to the technical field of radio direction finding, and relates to a high-precision interferometer.

Background

The interferometer direction finding technology uses different phase responses generated when the same phase wave front of the radiation source electromagnetic wave in the propagation direction reaches the sensors (usually a multi-element antenna array) which are separated in space, and the phase relation between the phase responses is formed by the phase responses. The interferometer is divided into a double-channel interferometer and a multi-channel interferometer according to the number of channels, and is divided into a single baseline interferometer, a double baseline interferometer, a multi-baseline interferometer and the like according to the number of baselines. In order to improve lateral accuracy, a three-channel long-and-short baseline interferometer is generally used, the short baseline is used for resolving ambiguity, and the long baseline is used for improving direction-finding accuracy, as shown in fig. 1 and 2.

In interferometer design, it is generally desirable to improve the angle measurement accuracy as much as possible at a low cost.

The cost of an interferometer is limited by the number of antennas and the number of rf channels, typically one antenna for each rf channel. Where the cost of the rf path is much greater than the cost of the antenna.

From the principle of interferometers, there are two factors that restrict the accuracy of angle measurement: firstly, the base line length is longer, and the accuracy is higher; the second is the incoming wave direction, when the length of the base line is unchanged, the accuracy is the highest when the incoming wave direction is perpendicular to the base line, and the accuracy is the worst when the incoming wave direction is parallel to the base line (namely, the incident angle is near 90 degrees).

In order to solve the problem of poor angle measurement accuracy when the incoming wave direction is nearly parallel to the baseline, a servo system is usually installed below the interferometer, and the direction of the incoming wave can be adjusted in real time, but the volume and the cost of the servo system are high.

In order to improve the angle measurement precision as much as possible under the condition of lower cost, the design scheme of the interferometer with low cost and high precision is innovatively provided by the patent.

Disclosure of Invention

Objects of the invention

The purpose of the invention is: aiming at the problems that when the incoming wave direction is nearly parallel to the base line, the angle measurement precision is poor, the cost is increased while the precision is improved by installing a servo system, the low-cost high-precision interferometer is provided, and the angle measurement precision is improved with low cost.

(II) technical scheme

In order to solve the above technical problems, the present invention provides a high-precision interferometer, which includes an antenna array, a radio frequency channel, and a baseband processing module; the antenna array is connected with a radio frequency channel, the radio frequency channel is connected with the baseband processing module, the antenna array comprises six antennas, wherein four antennas form two mutually vertical long baselines, and the other two antennas are combined with two of the four antennas to form two mutually vertical short baselines; the three radio frequency channels are respectively communicated with the corresponding antennas through the selector switch, and the incident angle is calculated through the baseband processing module and is used for measuring the incident angle of the incident wave in real time.

(III) advantageous effects

According to the low-cost high-precision interferometer provided by the technical scheme, the angle measurement precision is improved under the condition of low cost by adding the antenna array; by adding a base line perpendicular to the original base line, incident waves are ensured to be incident from any direction, and the included angle between the perpendicular line with the base line and the incident waves is always less than or equal to 45 degrees; through the way of channel switch switching, only increase the antenna, do not increase the radio frequency channel, control cost.

Drawings

FIG. 1 is a schematic diagram of long and short baseline interferometer angle measurement.

Fig. 2 is a schematic diagram of the connection between the long and short baseline interferometer antennas and the rf channel.

FIG. 3 is a schematic diagram of low cost and high precision interferometer angle measurement.

FIG. 4 is a schematic diagram of the connection of a low cost high precision interferometer antenna to a radio frequency channel.

Detailed Description

In order to make the objects, contents and advantages of the present invention clearer, the following detailed description of the embodiments of the present invention will be made in conjunction with the accompanying drawings and examples.

Referring to fig. 3, the high-precision interferometer of the present embodiment includes an antenna array, a radio frequency channel, and a baseband processing module; the antenna array is connected with a radio frequency channel, the radio frequency channel is connected with the baseband processing module, the antenna array comprises six antennas, wherein four antennas form two mutually vertical long baselines, and the other two antennas are combined with two of the four antennas to form two mutually vertical short baselines; the three radio frequency channels are respectively communicated with the corresponding antennas through the selector switch, and the incident angle is calculated through the baseband processing module and is used for measuring the incident angle of the incident wave in real time.

The six antennas of the antenna array are respectively marked as an antenna A1, an antenna A2, an antenna A3, an antenna B1, an antenna B2 and an antenna B3, the antenna A1 and the antenna A3 form a long base line, the antenna B1 and the antenna B3 form a second long base line, and the two long base lines are perpendicular to each other; antenna a1 and antenna a2 form a short baseline, and antenna B1 and antenna B2 form a second short baseline, which are perpendicular to each other.

Antenna a2 is disposed between antenna a1 and antenna A3, and antenna B2 is disposed between antenna B1 and antenna B3.

The lengths of the two long baselines are equal or unequal, but the length is set as long as possible so as to improve the angle measurement precision, the specific length is limited by the size of the interferometer mounting platform, and the length of each long base line is not less than the length of the mounting platform corresponding to the mounting position of the long base line, for example: when the interferometer is mounted on a vehicle, the length of the long base line may be equal to or longer than the length of the vehicle because the antenna a1 and the antenna A3 are arranged along the longitudinal direction of the vehicle body.

The lengths of the two short baselines are equal or unequal, and the length of the short baselines is limited by the incoming wave wavelength and is less than half of the incoming wave wavelength.

Referring to fig. 4, based on the high-precision interferometer, the real-time measurement process of the incident angle of the incident wave is as follows:

firstly, controlling a change-over switch to enable an antenna A1 to be connected with a radio frequency channel 1, an antenna A2 to be connected with a radio frequency channel 2, and an antenna A3 to be connected with a radio frequency channel 3, and calculating the incident angle of incident waves

Second, judging the incident angle of the incident waveWhether the angle is greater than 45 degrees or not, and if the angle is not greater than 45 degrees, the angle is used as a real measuring angle of the incident wave; if the angle is larger than 45 degrees, controlling a change-over switch to enable an antenna B1 to be connected with the radio frequency channel 1, an antenna B2 to be connected with the radio frequency channel 2, an antenna B3 to be connected with the radio frequency channel 3, and calculating an incident wave incident angle beta;

thirdly, judging whether the incident angle beta of the incident wave is greater than 45 degrees or not, and if not, taking the angle as the real measurement angle of the incident wave; such asIf the angle is larger than 45 degrees, the change-over switch is controlled to enable the antenna A1 to be connected with the radio frequency channel 1, the antenna A2 to be connected with the radio frequency channel 2, the antenna A3 to be connected with the radio frequency channel 3 and to merge the incident angles of the radio waves

And fourthly, repeating the second step and the third step to measure the incident angle of the incident wave in real time.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.