JP2013160562A - Tracking antenna device and method for controlling tracking antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a communication operating rate by easing a constraint condition of a place where a tracking antenna is installed and avoiding an occurrence of blocking between an opposed antenna and the tracking antenna.SOLUTION: A tracking antenna device performs radio communication between the tracking antenna installed on a mobile body and the opposed antenna, with an orientation direction of the tracking antenna set to the opposed antenna. The tracking antenna device includes: a moving device for moving the tracking antenna in a self-propelled manner; and moving control means that, when predicting an occurrence of blocking between the tracking antenna and the opposed antenna, controlling the moving device to move the tracking antenna to a location where no blocking occurs on the basis of a reception signal level of the tracking antenna, position information and attitude information of the tracking antenna, and shape data of a structure constituting the mobile body.

Description

  The present invention relates to a tracking antenna device and a tracking antenna control method provided in a moving body that performs line-of-sight communication with an opposing antenna of a satellite or a ground base station.

  Since satellite communication has a wide service area, it is widely used in mobile bodies such as marine vessels, aircraft, and trains where it is difficult to use ground lines. However, geostationary satellites used in broadband communications and the like are arranged at geostationary orbits at intervals of 2 to 4 degrees, and there is a risk of interference with other satellites if the antenna direction of the earth station deviates. is there. On the other hand, geostationary satellites are 36,000 km away from the ground and have a very large propagation loss. For example, when using the Ku band, which provides services to ships, it is necessary to use a large antenna of at least 60 cm or more. However, the directivity of an antenna of this size is sharp and the beam width becomes as narrow as about 2 degrees. For this reason, when installing an earth station antenna device on a mobile object such as a ship, aircraft, or train, a tracking mechanism that mechanically controls the antenna directivity (elevation angle and azimuth angle) is provided. A tracking antenna device is used in which the antenna is always directed in the satellite direction with respect to fluctuations (Non-Patent Document 1).

Higaki, Tsuchiya, “Design method of vibration isolation mechanism and tracking control system for marine broadband antenna”, IEICE Transactions 2008/12 Vol.J91-B No.12 4-3-12 Selecting the operation location p.29 www.lascom.or.jp/member/iomver/iomver4 303.pdf

  For example, when installing a tracking antenna device on a ship, considering the ship's position (latitude / longitude), azimuth, and inclination of the ship due to shaking, the azimuth angle is 360 degrees and the elevation angle is 0-90 degrees. It is desirable to install it in a place where it can be secured. However, depending on the structure of the ship, the tracking antenna may not be installed in a place where such a line of sight can be secured. In this case, as shown in FIG. 3, the tracking antenna 50 tracks the satellite 52 as the ship 51 moves to change the pointing direction, but the structure of the ship 51 is between the tracking antenna 50 and the satellite 52. When radio waves are blocked (blocked) as an obstacle, communication is disabled.

  Furthermore, in order not to radiate unnecessary waves toward other satellites due to reflection / diffraction by obstacles, if there is an obstacle within 3 degrees when looking at the satellite direction from the tracking antenna, the communication signal is stopped. Is taken (Non-Patent Document 2). As described above, when the line of sight between the satellite and the tracking antenna is interrupted, there may occur a time during which communication cannot be performed for a certain period of time.

The present invention is to alleviate the location constraint for installing the tracking antenna, to improve the communication operation rate to avoid blocking occurs between the opposed antenna and tracking antenna satellite or terrestrial base stations It is an object of the present invention to provide a tracking antenna device and a tracking antenna control method that can perform tracking.

  A first aspect of the present invention is a tracking antenna apparatus that performs radio communication between a tracking antenna and an opposing antenna with a pointing direction of a tracking antenna installed on a moving body directed to the opposing antenna, and a mobile apparatus that moves the tracking antenna by self-running The occurrence of blocking between the tracking antenna and the opposing antenna based on the received signal level of the tracking antenna, the position information and attitude information of the tracking antenna, and the shape data of the structure constituting the moving object And a movement control means for controlling the moving device to move the tracking antenna to a position where blocking does not occur.

  In the tracking antenna device of the first invention, the movement control means includes a position / attitude sensor that detects position information and attitude information of the tracking antenna, a data memory that stores shape data of a structure constituting the moving body, and a position -Calculates the pointing direction of the tracking antenna with respect to the opposing antenna based on the position information and posture information of the tracking antenna input from the posture sensor, and further calculates the direction of the structure based on the pointing direction and the shape data of the structure input from the data memory. The angle between the contour is calculated, and if the angle is equal to or less than the first threshold, the occurrence of blocking is predicted by the blocking occurrence prediction calculating means for predicting the occurrence of blocking by the structure and the blocking occurrence prediction calculating means. Sometimes, based on the position information and attitude information of the tracking antenna and the shape data of the structure, the angle is the first It calculates the moving position of the tracking antenna exceeds the value, controlling the moving device to and a movement processing unit for moving the tracking antenna to the mobile position.

  In the tracking antenna device of the first invention, the movement control means includes a received signal level detecting means for detecting a received signal level of the tracking antenna, and a received signal level input from the received signal level detecting means is not more than a second threshold value. For example, when the occurrence of blocking is predicted by the blocking occurrence prediction calculating means for predicting the occurrence of blocking and the blocking occurrence prediction calculating means, the moving device is controlled and the tracking antenna is moved until the received signal level exceeds the second threshold value. Movement processing means to be provided.

  A second invention is a tracking antenna control method for performing wireless communication between a tracking antenna and an opposing antenna by directing a pointing direction of the tracking antenna installed in a moving body to the opposing antenna, and a received signal level of the tracking antenna; Based on the position information and attitude information of the tracking antenna and the shape data of the structure constituting the moving body, the movement control means predicts the occurrence of blocking between the tracking antenna and the opposing antenna, and the movement control means detects the moving device. And the tracking antenna is moved to a position where blocking does not occur.

  In the tracking antenna control method of the second invention, the movement control means calculates the pointing direction of the tracking antenna with respect to the opposing antenna based on the position information and posture information of the tracking antenna input from the position / posture sensor, and further And the contour of the structure based on the shape data of the structure constituting the moving body input from the data memory, and if the angle is less than or equal to the first threshold value, occurrence of blocking by the structure Based on the position information and attitude information of the tracking antenna and the shape data of the structure, the movement position of the tracking antenna whose angle exceeds the first threshold is calculated, and the movement antenna is controlled to control the tracking antenna. Move to.

  In the tracking antenna control method according to the second invention, the movement control means predicts the occurrence of blocking if the received signal level of the tracking antenna input from the received signal level detection means is equal to or lower than the second threshold value, and controls the mobile device. The tracking antenna is moved until the received signal level exceeds the second threshold.

  In the present invention, when the occurrence of blocking is predicted due to the obstacle of the moving object in the direction of the tracking antenna, blocking occurs by moving the tracking antenna to a position where blocking does not occur. Time can be reduced and communication operation rate can be improved. Conventionally, it was necessary to ensure visibility in all directions when installing the tracking antenna, but it is not always necessary to ensure visibility in all directions at the time of installation. The degree of freedom can be improved.

It is a figure which shows the Example outline | summary of the tracking antenna apparatus of this invention. It is a figure which shows the Example structure of the tracking antenna apparatus of this invention. It is a figure explaining the subject of the conventional tracking antenna apparatus.

FIG. 1 shows an outline of an embodiment of the tracking antenna apparatus of the present invention.
In FIG. 1, the tracking antenna device of the present invention is characterized in that the tracking antenna 10 moves to a position where a line-of-sight between the tracking antenna 10 and the satellite 52 is secured. That is, if the tracking antenna device predicts that blocking will occur due to an obstacle between the tracking antenna 10 and the satellite 52 as the ship 51 moves or swings, the prospect of the tracking antenna 10 and the satellite 52 is secured. The tracking antenna 10 is moved to the position to be blocked, and communication interruption due to blocking is avoided in advance.

FIG. 1 (2) shows the moving direction of the tracking antenna in which the angle θ formed by the directing direction of the tracking antenna and the outline of the structure exceeds a predetermined threshold θ ₁ and no blocking occurs.

FIG. 2 shows the configuration of an embodiment of the tracking antenna apparatus of the present invention.
In FIG. 2, the tracking antenna device includes a tracking antenna 10, a movement control unit 20, and a moving device 30. The movement control unit 20 includes a reception signal level detection unit 21, a position / attitude sensor 22, a data memory 23, a blocking occurrence prediction calculation unit 24, and a movement processing unit 25.

  The reception signal level detection unit 21 detects the reception signal level obtained by the tracking antenna 10. The position / orientation sensor 22 is a GPS sensor, a gyro sensor, or the like attached to the ship 51 or the tracking antenna device itself, and outputs position (latitude / longitude) information and attitude (azimuth and inclination) information of the tracking antenna 10. The data memory 23 stores the route information of the ship 51 and the shape data of the structure.

  The blocking occurrence prediction calculation unit 24 inputs the received signal level of the tracking antenna 10, the position information and attitude information of the tracking antenna 10, the route information of the ship 51, and the shape data of the structure, and accompanies movement and swinging of the ship 51. Processing to predict the occurrence of blocking. When the occurrence of blocking is predicted by the blocking occurrence prediction calculation unit 24, the movement processing unit 25 calculates a movement position or movement direction in which blocking does not occur based on each piece of information used in the prediction calculation process, and the movement The moving device 30 is notified of the position or moving direction. The moving device 30 causes the tracking antenna 10 to move by itself in the moving position or moving direction. As a result, the tracking antenna 10 always has a line-of-sight with the satellite 52, and communication interruption due to blocking can be avoided in advance.

  Here, the calculation processing procedure of the blocking occurrence prediction calculation unit 24 and the movement processing unit 25 will be specifically described.

The blocking occurrence prediction calculation unit 24 calculates the pointing direction of the tracking antenna 10 with respect to the satellite 52 based on the current position, direction, inclination, and navigation information of the ship 51 obtained from the position information and attitude information of the tracking antenna 10. Further, based on the shape data of the structure of the ship 51, an angle θ between the pointing direction and the contour of the structure based on the shape data of the structure is calculated, and whether or not the angle θ is equal to or less than a threshold θ ₁ Determine. Here, θ ₁ is a value set at the time of operation, and is set to θ ₁ = 3 degrees based on the wave stopping criterion of Non-Patent Document 2. If θ ≦ θ ₁ , the pointing direction of the tracking antenna 10 and the structure are close to each other, and the movement processing unit 25 is notified that the occurrence of blocking is predicted. The movement processing unit 25 determines that the angle θ between the pointing direction and the structure is θ> θ ₂ > θ ₁ based on the current position, direction, inclination, route information and structure shape data of the ship 51.
That is, that is, the moving position or moving direction of the tracking antenna 10 that avoids the occurrence of blocking is calculated, and the moving position or moving direction is notified to the moving device 30. The mobile device 30 causes the tracking antenna 10 to self-run and move in the moving position or moving direction, and avoids communication interruption due to blocking in advance.

Further, when the blocking occurrence prediction calculation unit 24 normalizes the average received signal level in the normal state as 1, the received signal level A is equal to or less than the threshold value A ₁ (value set during operation, 0 ≦ A ₁ <1). In this case, the movement processing unit 25 is notified that the occurrence of blocking due to an obstacle is predicted. This assumes a countermeasure against blocking by an external structure such as a bridge or a building that does not have shape data of the structure. At this time, since the movement processing unit 25 cannot calculate the movement position that avoids blocking of the tracking antenna 10, the received signal level A is 1 ≧ A> A ₂ > A _1.
A movement command signal including a movement direction is output to the moving device 30 until a moving position is found. Then, blocking generating prediction calculating unit 24, when the received signal level A being monitored exceeds a threshold value A _2, to stop the movement command signal to the mobile device 30 via the mobile processing unit 25.

  The blocking occurrence prediction calculation unit 24 is based on the current position, direction, inclination, and navigation information of the ship 51 obtained from the position information and attitude information of the tracking antenna 10, the shape data of the structure, and the received signal level. Control for moving the tracking antenna 10 to a position satisfying the two control conditions simultaneously may be performed.

  Further, the moving range of the tracking antenna 10 is not only a straight line movement but also a three-dimensional movement including a curved line, a two-dimensional plane movement, and a vertical direction depending on the situation of the installation location of the moving body such as the ship 51. Also good. Moreover, you may move the tracking antenna 10 autonomously so that a received signal level may become the maximum.

  In addition, the present invention is not limited to a satellite, and can be similarly applied to a wireless system that performs line-of-sight communication between an opposing antenna of a ground base station and a tracking antenna of a mobile object.

DESCRIPTION OF SYMBOLS 10 Tracking antenna 20 Movement control part 21 Received signal level detection part 22 Position / attitude sensor 23 Data memory 24 Blocking generation | occurrence | production prediction calculation part 25 Movement processing part 30 Mobile device 50 Tracking antenna 51 Ship 52 Satellite

Claims (6)

In the tracking antenna device that directs the directivity direction of the tracking antenna installed on the moving body to the opposing antenna and performs wireless communication between the tracking antenna and the opposing antenna,
A mobile device for self-propelled movement of the tracking antenna;
Based on the received signal level of the tracking antenna, the position information and attitude information of the tracking antenna, and the shape data of the structure constituting the moving body, occurrence of blocking between the tracking antenna and the counter antenna is performed. A tracking antenna device, comprising: a movement control unit that controls the moving device to move the tracking antenna to a position where the blocking does not occur when predicted. The tracking antenna device according to claim 1,
The movement control means includes
A position / attitude sensor for detecting position information and attitude information of the tracking antenna;
A data memory for storing shape data of a structure constituting the moving body;
Based on position information and posture information of the tracking antenna input from the position / posture sensor, a directivity direction of the tracking antenna with respect to the opposing antenna is calculated, and further, the directivity direction and the shape of the structure input from the data memory Calculating an angle between the contour of the structure based on the data and predicting the occurrence of blocking by the structure if the angle is equal to or less than a first threshold;
Based on the position information and attitude information of the tracking antenna and the shape data of the structure, when the blocking occurrence prediction calculation unit predicts the occurrence of blocking, the moving position of the tracking antenna whose angle exceeds the first threshold A tracking antenna device, comprising: a movement processing unit that calculates the following and controls the moving device to move the tracking antenna to the moving position. The tracking antenna device according to claim 1,
The movement control means includes
Received signal level detecting means for detecting a received signal level of the tracking antenna;
A blocking occurrence prediction calculating means for predicting the occurrence of the blocking if the received signal level input from the received signal level detecting means is equal to or lower than a second threshold;
Movement processing means for controlling the mobile device when the blocking occurrence prediction calculating means predicts the occurrence of blocking, and moving the tracking antenna until the received signal level exceeds a second threshold. A characteristic tracking antenna device. In the tracking antenna control method in which the directivity direction of the tracking antenna installed on the moving body is directed to the opposing antenna and wireless communication is performed between the tracking antenna and the opposing antenna,
Based on the received signal level of the tracking antenna, the position information and attitude information of the tracking antenna, and the shape data of the structure that constitutes the moving body, the movement control means determines whether the movement control means is between the tracking antenna and the opposing antenna. Predict the occurrence of blocking,
The tracking antenna control method, wherein the movement control means controls a moving device to move the tracking antenna to a position where the blocking does not occur. In the tracking antenna control method according to claim 4,
The movement control means includes
A structure for calculating the directivity direction of the tracking antenna with respect to the counter antenna based on the position information and the posture information of the tracking antenna input from the position / attitude sensor and further configuring the moving body input from the directivity direction and the data memory Calculate the angle between the contour of the structure based on the shape data of the object, and predict the occurrence of blocking by the structure if the angle is equal to or less than the first threshold,
Based on the position information and attitude information of the tracking antenna and the shape data of the structure, the moving position of the tracking antenna whose angle exceeds a first threshold is calculated, and the moving antenna is controlled to control the tracking antenna. A tracking antenna control method characterized by moving to a moving position. In the tracking antenna control method according to claim 4,
The movement control means includes
If the received signal level of the tracking antenna input from the received signal level detection means is equal to or lower than a second threshold, the occurrence of the blocking is predicted,
A tracking antenna control method, comprising: controlling the moving device to move the tracking antenna until the received signal level exceeds a second threshold value.

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