JP2019007874A - Satellite capturing device and satellite capturing method - Google Patents

Abstract

To prevent a procedure for readjusting the direction of antenna orientation from being inadvertently activated.SOLUTION: According to an embodiment, a satellite capturing device comprises an antenna for receiving a radio wave from an artificial satellite, as well as a strength calculation unit, a position sensor, a determination unit, an attitude sensor, a search unit and a reexecution control unit. The strength calculation unit calculates the received strength of a radio wave. The position sensor acquires position information at an installation site. The determination unit determines an artificial satellite search range from the installation site on the basis of the acquired position information. The attitude sensor detects the attitude of the antenna at the installation site. The search unit executes an automatic adjustment procedure for adjusting the direction of antenna orientation within the search range on the basis of received strength. The reexecution control unit reexecutes the automatic adjustment procedure when the received strength decreases to or below a prescribed value and a change amount of attitude increases to or above a threshold after the automatic adjustment procedure is completed.SELECTED DRAWING: Figure 3

Description

  Embodiments described herein relate generally to a satellite capturing device and a satellite capturing method applicable to, for example, a satellite communication device.

  VSAT (Very Small Aperture Terminal) is a device having a relatively small antenna aperture among communication devices for communicating with geostationary satellites. In recent years, further miniaturization has progressed, for example, there are devices that have been miniaturized so that they can be mounted on a car or carried by one person. Also, it is often used in conjunction with mobile communication infrastructure.

  By the way, in order to communicate with the satellite, the satellite must be accurately captured and the antenna surface must be correctly directed toward the satellite. Conventionally, adjustment of the antenna angle has depended on the skill of a skilled person, but in recent years, a method of automatically capturing a satellite by a tracking mechanism has been proposed. For example, a technique is known in which received power (received radio wave intensity) is measured while rotating an antenna with a driving device, and a satellite is captured by directing the antenna in the direction of the maximum level. Specifically, by adjusting the three axes of the antenna azimuth angle (AZ (Azimuth) angle), elevation angle (EL (Elevation) angle), and polarization angle (POL (Polarization) angle), Detect the signal strength.

JP 2008-294540 A Japanese Patent Laid-Open No. 2-148902

  After the adjustment of the antenna angle is completed and the operation is started, the antenna pointing direction may be deviated for some reason. In such a case, the radio wave from the satellite cannot be received, and other satellite communication systems will have adverse effects such as interference, so immediately stop the radio wave and execute the automatic adjustment procedure for the antenna pointing direction again. There is a need to.

  However, in the existing technology, an automatic adjustment procedure may be activated even in a case where it is not originally necessary, such as when an automobile or a person crosses the front of the antenna or only a cloud is applied to the sky. If the automatic adjustment procedure is inadvertently started, satellite communication cannot be performed during that time, and the user waits until resumption. Countermeasures are desired because the service quality is also degraded.

  Accordingly, an object of the present invention is to provide a satellite capturing device and a satellite capturing method that prevent an antenna orientation direction readjustment procedure from being inadvertently activated.

  According to the embodiment, the satellite capturing device includes an antenna that receives radio waves from an artificial satellite, an intensity calculation unit, a position sensor, a determination unit, an attitude sensor, a search unit, and a re-execution control unit. It has. The intensity calculation unit calculates the reception intensity of the radio wave. The position sensor acquires position information at the installation location. The determination unit determines a search range of the artificial satellite from the installation location based on the acquired position information. The attitude sensor detects the attitude of the antenna at the installation location. A search part performs the automatic adjustment procedure for adjusting the directivity direction of an antenna within a search range based on reception intensity. The re-execution control unit re-executes the automatic adjustment procedure when the reception intensity becomes equal to or less than a specified value and the change amount of the posture becomes equal to or greater than the threshold value after the automatic adjustment procedure is completed.

The figure which shows an example of the satellite communication system using VSAT. 1 is an external view illustrating an example of a satellite communication device according to an embodiment. The functional block diagram which shows an example of the satellite communication apparatus 1 shown by FIG. The figure which shows an example of the azimuth | direction information 44a. The figure which shows an example of the satellite target angle table 44b. The flowchart which shows an example of the process sequence of the satellite communication apparatus 1 in 1st Embodiment. The flowchart which shows an example of the process sequence in the operation mode after the automatic adjustment procedure is completed in 1st Embodiment. The figure which shows an example of the time fluctuation | variation of the reception power of the electromagnetic wave from a satellite in 2nd Embodiment. 12 is a flowchart illustrating another example of a processing procedure in the operation mode according to the third embodiment. The flowchart which shows the other example of the process sequence in operation mode in 4th Embodiment.

  FIG. 1 is a diagram illustrating an example of a satellite communication system using VSAT. This system is formed with a communication satellite SAT in geostationary orbit as a core. On the ground side, fixed stations 111 and 114 to 11n are installed, for example, at the prefectural office location. The in-vehicle station 112 or the portable station 113 can be installed at a disaster site or the like. Each of the fixed stations 111, 114 to 11n, the in-vehicle station 112, and the portable station 113 includes a VSAT device and can communicate with each other via the communication satellite SAT.

  For example, the image of the disaster site can be transmitted to a main site (fixed station 111) or each site (fixed stations 114 to 11n) via a satellite line to help grasp the disaster situation. It can also be used for information sharing and disaster response discussions between related departments through VoIP (Voice over IP) calls and TV conferences over satellite channels.

  This type of system is often built as one of the local government disaster prevention systems. The line assignment method for the VSAT device is called DAMA (Demand Assignment Multiple Access). Control stations provided at several points on the ground take control of DAMA.

  FIG. 2 is an external view illustrating an example of the satellite communication device according to the embodiment. The satellite communication device 1 shown in FIG. 2 is a so-called VSAT device and has a function as a satellite capturing device. The size of the satellite communication device 1 is compact enough to be carried by the user, and the weight is also suppressed. The satellite communication device 1 can be used as an emergency communication station by being carried to a disaster site, for example.

  A satellite communication device 1 shown in FIG. 2 includes an antenna 10, a main body 11, a tripod 12 that supports the main body 11, struts 13 b and 13 c that physically connect the main body 11 and the antenna 10, and a transmission / reception unit 18. Prepare. The main body 11 is a so-called computer including a processor (CPU (Central Processing Unit) or MPU (Micro Processing Unit)) and a memory.

  The antenna 10 receives radio waves from the artificial satellite and transmits radio waves toward the artificial satellite. The size of the antenna 10 is, for example, 50 cm × 50 cm. As the antenna type, a parabolic antenna can be used in addition to the planar antenna shown in the figure. In order to minimize the energy loss of radio waves, the directivity of the antenna 10 is sharply designed. For this reason, it is necessary to accurately match the azimuth angle (AZ angle), elevation angle (EL angle), and polarization angle (POL angle) to the satellite, which are three different axes.

  The transmission / reception unit 18 frequency-converts a radio frequency band signal transmitted / received via the antenna 10 into, for example, a baseband signal. For example, by attaching the transmission / reception unit 18 to the back surface of the antenna 10 so as to be close to the antenna 10, attenuation of the transmission signal and the reception signal can be suppressed.

  Further, for example, an orientation sensor 60 that acquires orientation information is attached to the back surface of the antenna 10. By installing the azimuth sensor 60 on the antenna 10, the azimuth sensor 60 can be horizontally rotated along the azimuth axis. Further, the azimuth sensor 60 can be rotated by using both the antenna 10 and the motor 20, so that the cost of the apparatus can be reduced.

  The column 13b is provided, for example, perpendicular to the upper surface (upper surface in FIG. 1) of the main body 11 and rotates in the rotation direction A that is an azimuth angle (AZ angle) with respect to the main body 11. The support column 13c is attached to the support column 13b so as to be semi-fixed and rotatable, and rotates in a rotation direction B that is an elevation angle (EL angle) with respect to the support column 13b. The struts 13b and 13c may have a folding mechanism. If the support columns 13b and 13c are folded, the satellite communication device 1 can be further reduced in size, and the satellite communication device 1 can be easily handled.

  Motors 20a and 20b are attached to the column 13b. A motor 20c is attached to the column 13c. Each motor is controlled by a control signal from the motor control unit 202. The motor 20a rotates the antenna 10 around the axis in the rotation direction A (azimuth axis or AZ axis). The motor 20b rotates the antenna 10 around the axis in the rotation direction B (elevation angle axis or EL axis). The motor 20c rotates the antenna 10 around an axis in the rotation direction C (polarization axis or POL axis).

  The main body 11 includes a power button 14, a capture button 15, and a display device 90. The power button 14 is a button for switching the power of the satellite communication device 1 between ON and OFF. When the acquisition button 15 is operated after the device is turned on, the first satellite acquisition process starts, and the process for acquiring the satellite using the antenna 10 is started.

  The display device 90 is provided, for example, on the side surface of the main body 11 and displays the result of the satellite capture control process. The display device 90 may not be built in the satellite communication device 1 and may be a display device externally attached to the satellite communication device 1.

  FIG. 3 is a functional block diagram showing an example of the satellite communication device 1 shown in FIG. The main body 11 includes a capture control unit 40, a motor control unit 30, a received radio wave intensity calculation unit 50 that calculates the reception sensitivity of the antenna, a position sensor 70, a tilt sensor 71, a user input device 80, and a display device as a notification unit 90. A speaker 100 is provided.

  The motor control unit 30 gives a control signal to each of the motors 20 (20a, 20b, 20c) in response to an instruction from the capture control unit 40 regarding the directivity direction of the antenna 10. Thereby, the directivity direction of antenna 10 and direction sensor 60 attached to antenna 10 can be changed.

  The reception radio wave intensity calculation unit 50 calculates the reception sensitivity of the reception signal received by the antenna 10 and sends the obtained value to the capture control unit 40.

  The azimuth sensor 60 acquires azimuth information of the satellite communication device 1 by sensing geomagnetism. In conjunction with the driving of the antenna 10 by the motor 20, the orientation direction of the orientation sensor 60 also changes, and the acquired orientation information also changes. The acquired azimuth information is passed to the capture control unit 40.

  The position sensor 70 acquires position information (for example, latitude and longitude) of the installation location of the satellite communication device 1 by, for example, GPS (Global Positioning System). The acquired position information is passed to the capture control unit 40.

  The tilt sensor 71 acquires the tilt amount of the satellite communication device 1 at the installation location. For example, the amount of inclination of the satellite communication device 1 can be acquired by detecting the gravitational acceleration of the earth at the installation location using an acceleration sensor. The acquired inclination amount is passed to the capture control unit 40.

  Note that both the azimuth sensor 60 and the tilt sensor 71 can detect information related to the attitude of the satellite communication device 1. That is, the azimuth sensor 60 and the tilt sensor 71 have a function as an attitude sensor. The azimuth information output from the azimuth sensor 60 and the tilt amount output from the tilt sensor 71 can be used as an index indicating the attitude of the satellite communication device 1.

  The user input device 80 is a user interface for inputting an instruction from a user related to automatic capture control. The user input device 80 includes, for example, a touch panel for selecting a capture target satellite.

  The display device 90 displays information related to automatic capture control. For example, the current processing state (during calibration, satellite capture, tracking, etc.) may be displayed with an LED (Light Emitting Diode). Alternatively, capture results such as capture success and capture failure may be displayed on the liquid crystal panel together with the end code. The speaker 100 notifies the user of information related to automatic capture control with sound.

  The capture control unit 40 instructs the motor control unit 30 on the azimuth angle, elevation angle, and polarization angle of the antenna 10, and captures the target communication satellite by detecting the angle at which the reception sensitivity of the received signal reaches a peak. The acquisition control unit 40 includes a satellite search unit 41, an azimuth calculation unit 43, a re-execution control unit 45, and a storage unit 44. Among these, the memory | storage part 44 memorize | stores the azimuth | direction information 44a and the satellite target angle table 44b.

  FIG. 4 is a diagram illustrating an example of the direction information 44a. The azimuth information 44a is information in which the azimuth angle (azimuth information) of the satellite communication device 1 measured by the azimuth sensor 60 is associated with the geomagnetic intensity. The azimuth [°] and the geomagnetic intensity [micro tesla] may be recorded in association with the measurement type (initial, rotation, etc.) and the measurement time.

  FIG. 5 is a diagram illustrating an example of the satellite target angle table 44b. The satellite target angle table 44b is a table in which position information (for example, latitude and longitude) on the ground is associated with satellite target angles (azimuth angle, elevation angle, and polarization angle) of communication satellites to be captured. For example, as shown in FIG. 5, the latitude of Sapporo, Hokkaido is 141.4 ° and the longitude is 43.1 °, and the target angle of the communication satellite A at this position is (azimuth angle, elevation angle, polarization angle) = (151.2 °, 36.1 °, 10.4 °).

  Returning to FIG. 2, the description will be continued. The satellite search unit 41 adjusts the angle of the antenna 10 while monitoring the received radio wave intensity from the satellite, and acquires the satellite by searching for the peak position of the received radio wave intensity. A series of sequences for adjusting the directivity direction of the antenna 10 within the search range based on the received radio wave intensity is referred to as an automatic adjustment procedure.

That is, the satellite search unit 41 acquires the satellite target angle corresponding to the position acquired by the position sensor 70 from the satellite target angle table 44b. Then, a search range including the satellite target angle is set, and the artificial satellite is searched by directing the antenna 10 in the search range. At that time, the satellite search unit 41 searches the search range by controlling the direction of the antenna 10 based on the direction information acquired by the direction sensor 60.
The azimuth calculation unit 43 calculates the azimuth angle of the antenna 10 that changes as the antenna 10 rotates about three axes.

  The re-execution control unit 45 acquires the received radio wave intensity from the received radio wave intensity calculating unit, acquires the azimuth information from the azimuth sensor 60, and acquires the tilt amount from the tilt sensor 71. Then, after the automatic adjustment procedure by the satellite search unit 41 is completed, the re-execution control unit 45 has a reception intensity that is equal to or less than a specified value, and a change amount of the attitude of the satellite communication device 1 is equal to or greater than a threshold value. A trigger is given to the satellite search unit 41 to execute (retry) the automatic adjustment procedure again. Note that when the amount of change in posture is greater than or equal to the threshold, the amount of change in inclination is greater than or equal to the threshold, or the amount of change in orientation information is greater than or equal to the threshold, or both cases. This is the case. Next, an embodiment of the present invention will be described based on the above configuration.

[First Embodiment]
FIG. 6 is a flowchart illustrating an example of a processing procedure of the satellite communication device 1 according to the first embodiment. The procedure shown in FIG. 6 is performed in a preparatory process before the satellite communication device 1 is installed in a predetermined place and starts operation.

  In FIG. 6, the satellite communication apparatus 1 detects the longitude and latitude of the place where the satellite communication apparatus 1 is installed using the position sensor 70 (step S10).

  Next, the satellite communication device 1 searches the satellite target angle table 44b from the latitude and longitude of the position information detected in step S10, and determines the azimuth angle, elevation angle, and polarization angle of the satellite to be captured (step S11). . Here, the satellite to be captured may be preset in the apparatus, or may be selected from the user input device 80.

  Next, the satellite communication device 1 acquires the tilt angle from the tilt sensor 71 and acquires the azimuth angle of the antenna 10 from the azimuth sensor 60. The acquired tilt angle data is stored in the storage unit 44. Through the process so far, the attitude of the satellite communication device 1 can be determined (step S12). That is, it is possible to grasp which direction the satellite communication device 1 and the antenna 10 are facing. Next, the satellite communication device 1 determines the directivity direction of the antenna 10 based on the current antenna orientation and the satellite target angle (step S13).

  Next, based on the determined directivity direction of the antenna 10, the satellite communication device 1 executes a satellite acquisition sequence (step S14). In the satellite acquisition sequence (automatic adjustment procedure), the satellite communication device 1 adjusts the directivity direction of the antenna 10 within the search range including the satellite target angle based on the received radio wave intensity. If the received power of a certain value or more can be obtained, the satellite acquisition sequence is completed (Yes in step S15), and the operation mode is shifted.

  Even after shifting to the operation mode, environmental conditions such as weather conditions and radio wave environmental conditions change every moment. In some cases, it is necessary to re-execute the satellite acquisition sequence (satellite re-acquisition sequence), but it is desirable to correctly determine whether this is really necessary. Accordingly, a plurality of embodiments will be described below for the process of determining whether to activate the satellite reacquisition sequence.

  FIG. 7 is a flowchart illustrating an example of a processing procedure in the operation mode after the automatic adjustment procedure of the first embodiment is completed. In FIG. 7, the satellite communication device 1 acquires the received radio wave intensity (step S20), and if the value is equal to or less than the specified value (Yes in step S21), acquires the tilt angle data from the tilt sensor 71 and stores the storage unit 44. Is compared with the tilt angle data stored in. Thereby, the amount of change between the tilt angle data acquired in step S14 of FIG. 6 and the latest tilt angle data can be calculated. If the amount of change is lower than the threshold (No in step S23), the processing procedure returns to step S20 again.

  On the other hand, if the change amount of the tilt angle is equal to or greater than the threshold (Yes in Step S23), the satellite communication device 1 starts the satellite re-acquisition sequence (Step S24) and waits for the completion (Yes in Step S25). The mode continues again.

  As described above, in the first embodiment, when a decrease in received power is detected, a procedure for determining a threshold value for a change amount of an inclination angle is not performed immediately instead of blindly starting a satellite reacquisition sequence. Provide. Then, if the change amount of the tilt angle is equal to or greater than the threshold value, the satellite reacquisition sequence is started for the first time. As described above, in the first embodiment, the determination is performed based on different determination criteria over two stages.

  The existing technology relied solely on the received radio wave intensity as a key for adjusting the antenna pointing direction. That is, as soon as the radio wave arriving at the antenna 10 becomes weak, the retry sequence is activated, and the readjustment of the antenna directivity must be performed again from the beginning. As described above, when only the received power is used as the determination criterion, the automatic adjustment procedure starts immediately even if the antenna 10 is only temporarily blocked.

  On the other hand, in the first embodiment, in addition to the received power, a change in the tilt angle is also detected, and when the tilt angle changes, it is determined that the antenna orientation has changed, and an automatic adjustment procedure is performed. Thereby, it can prevent that the readjustment procedure of an antenna directivity direction starts carelessly. Therefore, unnecessary automatic satellite reacquisition operation is suppressed, and the period during which service provision is impossible can be eliminated as much as possible.

  In addition, in the first embodiment, the inclination data is acquired using the inclination sensor 71. Since the tilt sensor originally used in the satellite communication apparatus 1 can be used, there is no need to add a new device, and there is no possibility that the cost, weight, volume, etc. of the apparatus will increase.

[Second Embodiment]
FIG. 8 is a diagram illustrating an example of temporal variation in received power of radio waves from a satellite according to the second embodiment. As shown in the figure, the reception intensity of radio waves from the satellite may be temporarily reduced. Conventionally, when the received radio wave intensity decreases, an automatic adjustment procedure is started immediately after about 1 second at most [Δt seconds].

  There is a case where the received radio wave intensity does not recover as it is like the A curve. However, as indicated by the B curve, the received radio wave intensity may recover immediately after the start of the automatic adjustment procedure. Conventionally, even in the case of a B curve, the automatic adjustment procedure has already been started, and the time spent on it is wasted.

  Therefore, in the second embodiment, when the reception intensity is equal to or less than a specified value and a predetermined time (for example, about 10 seconds to several minutes) has elapsed in that state, the antenna pointing direction automatic adjustment procedure is executed again. I made it. Thereby, when the received radio wave intensity is recovered in a short period, the automatic adjustment procedure is not already executed, and the same effect as that of the first embodiment can be obtained.

[Third Embodiment]
FIG. 9 is a flowchart illustrating an example of a processing procedure in the operation mode after the automatic adjustment procedure in the third embodiment is completed. In FIG. 9, the same steps as those in FIG. 7 are denoted by the same reference numerals, and only different items will be described here.

  The procedure shown in FIG. 9 is started by first obtaining inclination data of the inclination sensor 71. And when the variation | change_quantity of the inclination amount from the last time is more than a regulation value, a received radio wave intensity | strength is acquired and threshold value determination is performed. That is, the automatic adjustment procedure is executed again when the amount of change in the tilt amount is equal to or greater than the threshold value and the received radio wave intensity is equal to or less than the specified value.

  If only the change amount of the tilt amount by the tilt sensor 71 is detected, an unnecessary automatic adjustment procedure may be activated even when the antenna 10 returns to the original position. Therefore, in the third embodiment, the received power is confirmed after the change in the data of the tilt sensor 71 is captured. Then, when the received power is equal to or less than the specified value, it is determined that the antenna orientation has changed, and an automatic adjustment procedure is performed. Even in this case, it is possible to prevent the readjustment procedure for the antenna directivity direction from being inadvertently activated.

[Fourth Embodiment]
FIG. 10 is a flowchart illustrating an example of a processing procedure in the operation mode after the automatic adjustment procedure in the fourth embodiment is completed. In FIG. 10, the same steps as those in FIG. 7 are denoted by the same reference numerals, and only different items will be described here.

  The procedure shown in FIG. 10 is obtained by providing steps S26 and S27 after step S23 shown in FIG. If it is determined in step S23 that the change amount of the tilt amount is equal to or greater than the threshold value, the satellite communication device 1 acquires data of the direction sensor 60 (step S26). Then, the azimuth information 44a of the azimuth sensor 60 stored in the storage unit 44 is compared with the latest azimuth information, and if the amount of change is equal to or greater than the threshold, the satellite communication device 1 starts the satellite reacquisition sequence (step) S24).

  The tilt sensor 71 may not be able to detect a slow change in tilt. Therefore, in the fourth embodiment, the azimuth sensor 60 is further used in combination with the result of the threshold determination of the received power to determine whether the automatic adjustment procedure can be restarted. In the fourth embodiment, so to speak, judgment criteria including three stages are provided, so that it is possible to prevent the readjustment procedure of the antenna directivity direction from being started carelessly with higher accuracy.

  The present invention is not limited to the above embodiment. For example, in the fourth embodiment, as shown in the flowchart of FIG. 10, the determination based on the change amount of the inclination data and the determination based on the change amount of the direction information are connected by an AND condition (logical product). Instead of this, the determination based on the change amount of the inclination data and the determination based on the change amount of the azimuth information may be connected with an OR condition (logical sum).

  In other words, the satellite re-acquisition sequence is started when the received radio wave intensity is less than the specified value and at least one of the change amount of the inclination data and the change amount of the azimuth information is equal to or greater than the threshold value. Also good. In this way, there is an effect that the accuracy of the inclination sensor 71 and the accuracy of the direction sensor 60 can be complemented with each other. In particular, when a relatively inexpensive magnetic sensor is used as the orientation sensor, desired accuracy may not be obtained. In such a case, if the data of the inclination sensor 71 is used, determination with higher accuracy can be performed.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Satellite communication apparatus, 10 ... Antenna, 11 ... Main part, 12 ... Tripod, 13b ... Column, 13c ... Column, 14 ... Power button, 15 ... Capture button, 18 ... Transmission / reception unit, 20 ... Motor, 20a ... Motor, 20b ... motor, 20c ... motor, 30 ... motor control unit, 40 ... capture control unit, 41 ... satellite search unit, 43 ... azimuth calculation unit, 44 ... storage unit, 44a ... azimuth information, 44b ... satellite target angle table, 45 ... Re-execution control unit, 50 ... Received radio wave intensity calculation unit, 60 ... Direction sensor, 70 ... Position sensor, 71 ... Tilt sensor, 80 ... User input device, 90 ... Display device, 100 ... Speaker, 111, 114-11n ... Fixed station, 112 ... In-vehicle station, 113 ... Portable station, 202 ... Motor controller.

Claims (10)

An antenna for receiving radio waves from an artificial satellite;
An intensity calculation unit for calculating the reception intensity of the radio wave;
A position sensor for acquiring position information at the installation location;
A determination unit for determining a search range of the artificial satellite from the installation location based on the acquired position information;
An attitude sensor for detecting the attitude of the antenna at the installation location;
A search unit that performs an automatic adjustment procedure for adjusting the directivity direction of the antenna within the search range based on the reception intensity;
A re-execution control unit configured to re-execute the automatic adjustment procedure when the reception intensity is equal to or less than a predetermined value after the automatic adjustment procedure is completed and the posture change amount is equal to or greater than a threshold value; , Satellite capture device. Furthermore, it comprises an orientation sensor that acquires orientation information of the antenna,
The satellite acquisition device according to claim 1, wherein the search unit adjusts a directivity direction of the antenna based on the orientation information. The posture sensor is a tilt sensor that acquires a tilt amount at the installation location,
2. The satellite acquisition according to claim 1, wherein the re-execution control unit re-executes the automatic adjustment procedure when the reception intensity is equal to or less than a predetermined value and the change amount of the tilt amount is equal to or greater than a threshold value. apparatus. The orientation sensor is an orientation sensor that acquires orientation information of the antenna,
2. The satellite acquisition according to claim 1, wherein the re-execution control unit re-executes the automatic adjustment procedure when the reception intensity is a predetermined value or less and a change amount of the azimuth information is a threshold value or more. apparatus.   The satellite acquisition device according to claim 1, wherein the re-execution control unit re-executes the automatic adjustment procedure when the reception intensity is equal to or less than a specified value and a predetermined time has elapsed in that state. A satellite acquisition method executed by a computer of a satellite acquisition device having an antenna for receiving radio waves from an artificial satellite,
A process in which the computer calculates the reception strength of the radio wave;
The computer obtains location information at the installation location;
A step in which the computer determines a search range of the artificial satellite from the installation location based on the acquired position information;
A process in which the computer detects an attitude of the antenna at the installation location by an attitude sensor;
The computer executing an automatic adjustment procedure for adjusting the directivity direction of the antenna within the search range based on the received intensity;
A step in which the computer executes the automatic adjustment procedure again when the reception intensity becomes a specified value or less and the change amount of the posture becomes a threshold value or more after the automatic adjustment procedure is completed. , Satellite acquisition method. Furthermore, the computer comprises a process of acquiring the direction information of the antenna by the direction sensor,
The satellite acquisition method according to claim 6, wherein the computer adjusts the directivity direction of the antenna based on the orientation information. The posture sensor is a tilt sensor that acquires a tilt amount at the installation location,
The satellite acquisition method according to claim 6, wherein the computer executes the automatic adjustment procedure again when the reception intensity is equal to or less than a predetermined value and the change amount of the tilt amount is equal to or greater than a threshold value. The orientation sensor is an orientation sensor that acquires orientation information of the antenna,
The satellite acquisition method according to claim 6, wherein the computer executes the automatic adjustment procedure again when the reception intensity is equal to or less than a specified value and the amount of change in the azimuth information is equal to or greater than a threshold value.   The satellite acquisition method according to claim 6, wherein the computer executes the automatic adjustment procedure again when the reception intensity is equal to or less than a specified value and a predetermined time has elapsed in that state.