Satellite communication system, control station device, and control method

Abstract

To provide a satellite communication system, a mobile station device, a control station device, and a control method, enabling reduction of human load required for an up-link access test.SOLUTION: In a satellite communication system comprising a control station device controlling a satellite on an orbit, and a mobile station device establishing a channel via the satellite and communicating with a ground station, the mobile station device comprises a test request unit and a transmission control unit. The test request unit transmits to the control station device a test request message, which requests to carry out a test on up-link communication with the satellite. The transmission control unit transmits a test carrier signal to the satellite. The control station 20 comprises a measurement unit, a determination unit 45a, and a notification unit 45b. The measurement unit obtains a measurement value by measuring a degree of cross polarization discrimination of the test carrier signal received via the satellite in a down link from the mobile station device which has transmitted the test request message. The determination unit determines a test result on the basis of the measurement value. The notification unit notifies the mobile station device of the test result.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] An embodiment of the present invention is a satellite communication system 、 The present invention relates to a control station device and a control method. [Background technology]

[0002] A satellite broadcasting system comprises terrestrial and vehicle-mounted stations on Earth, and artificial satellites in geostationary orbit. SNG (Satellite News Gathering) is one of the services provided using communication satellites (CS) and broadcasting satellites (BS). Broadcast waves from the ground are transmitted to the satellite via uplink, and the satellite relays the broadcast waves and retransmits them to the ground via downlink. Ku-band (14GHz / 12GHz) radio waves are used for two-way communication.

[0003] The antennas of fixed ground stations are optimally aligned to point toward the satellite when they are installed, so frequent alignment is not required. However, vehicle-mounted stations are mobile, so the antenna must be accurately pointed toward the satellite each time they move. Strict procedures must be followed to verify that the vehicle-mounted station is able to accurately capture the satellite and transmit radio waves. In other words, an Uplink Access Test (UAT) must be performed to verify that the Cross Polarization Discrimination (XPD) value of the UAT carrier transmitted from the vehicle-mounted station is within the correct range before the vehicle-mounted station is permitted to uplink transmit broadcast signals to the satellite. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-194701 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-37237 [Patent Document 3] Japanese Patent Application Laid-Open No. 2012-175217 [Non-patent literature]

[0005] [Non-Patent Document 1] "Development of new operational methods for SNG", [online], [Accessed June 10, 2021], Internet,<URL:https: / / www.jstage.jst.go.jp / article / itej / 73 / 2 / 73_381 / _pdf> Summary of the Invention [Problem to be solved by the invention]

[0006] UAT is carried out based on a request from the vehicle-mounted station to the control station, but the procedure is complicated and requires judgment based on specialized knowledge and experience. Currently, there are many human-related procedures, such as telephone contact between the vehicle-mounted station and the control station, and the final pass / fail decision is made by an experienced person, which places a heavy burden on the operator. It is impossible to know when or where a UAT request from the vehicle-mounted station will come from, especially during a disaster. For this reason, control station operators are required to be on standby at all times, which increases labor costs.

[0007] Additionally, in recent years, an operational form known as site diversity has been implemented, primarily as a precaution against disasters and bad weather. Site diversity is a form in which a secondary control station or other remotely located transmission facility is used to transmit and receive the carrier of the main control station (parent station) to and from the satellite, or to back up the control functions of the main control station. When control is taken over using site diversity, operations related to satellite control are performed by the main control station, but the actual transmission and reception of signals is carried out by the secondary control station's equipment. This requires complex communication between the onboard station, the main control station, and also the secondary control station, placing an ever-increasing burden on operators.

[0008] Therefore, the objective is to develop a satellite communication system that reduces the human burden involved in uplink access testing. 、The present invention provides a control station device and a control method thereof. [Means for solving the problem]

[0009] According to an embodiment, a satellite communications system includes a control station device that controls an orbiting satellite, and a mobile station device that establishes a link via the satellite and communicates with a ground station. The mobile station device includes a test request unit and a transmission control unit. The test request unit transmits a test request message to the control station device, requesting the implementation of a test related to uplink communications with the satellite, prior to establishing the link. The transmission control unit transmits a test carrier signal toward the satellite when the request is accepted. The control station device includes a measurement unit, a determination unit, and a notification unit. The measurement unit measures the cross polarization discrimination of the test carrier signal that arrives in the downlink via the satellite from the mobile station device that transmitted the test request message, to obtain a measurement value. The determination unit determines the result of the test based on the measurement value. The notification unit notifies the mobile station device of the test result. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing an example of a satellite communication system according to the first embodiment. [Figure 2] FIG. 2 is a block diagram showing an example of the vehicle-mounted station 10 shown in FIG. [Figure 3] FIG. 3 is a functional block diagram showing an example of the control station 20 shown in FIG. [Figure 4] FIG. 4 is a sequence diagram illustrating an example of a processing procedure according to the first embodiment. [Figure 5] FIG. 5 is a diagram showing an example of a GUI screen displayed on the display unit 17 of the vehicle-mounted station 10. As shown in FIG. [Figure 6] FIG. 6 is a diagram showing an example of a GUI screen displayed on the display unit 17 of the vehicle-mounted station 10. As shown in FIG. [Figure 7] FIG. 7 is a diagram showing an example of a satellite communication system according to the second embodiment. [Figure 8] FIG. 8 is a functional block diagram showing an example of the control station 20 and the sub-control station 50 shown in FIG. [Figure 9] FIG. 9 is a sequence diagram illustrating an example of a processing procedure according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] [First embodiment] <Configuration> FIG. 1 is a diagram showing an example of a satellite communication system according to a first embodiment. The satellite communication system includes an artificial satellite (satellite) in geostationary orbit, a ground station on the ground, and a mobile station device. For example, a mobile station device can be dispatched to a disaster site, and live video footage captured there can be received at a remote location on the ground via the satellite. SNG is known as one form of reporting of this type, and allows for quick and accurate information about the disaster situation.

[0012] The satellite communications system shown in Figure 1 comprises a satellite 100, a control station 20, ground stations 30 (31 to 3N), and a vehicle-mounted station 10. The control station 20 comprehensively manages the vehicle-mounted stations 10, ground stations 30, and base stations for operators who share a jointly contracted satellite line. The functions of the control station 20 are often performed by a key station (main station) in Tokyo or a key station (substation) in the Kinki or Tokai region. The vehicle-mounted station 10 establishes a communication line via the satellite 100 and communicates with the control station 20 and the ground station 30 via this communication line. The ground station 30 is installed in an affiliated station of a key station, a prefectural capital, a local government, or the like. The control station 20 checks whether the vehicle-mounted station 10 and the ground station 30 are capturing the satellite 100, and whether the frequency and transmission power are within the standards of the operational regulations. If there is a risk that the user of the vehicle-mounted station 10 or the ground station 30 is not operating the satellite 100 appropriately, the control station 20 will issue a corrective instruction or otherwise supervise and manage the base stations and vehicle-mounted stations as joint users of the satellite 100.

[0013] In Fig. 1, for example, a signal transmitted in uplink from a vehicle-mounted station 10 is received by a satellite 100 and then transmitted in downlink from the satellite 100 to the ground. The communication line includes a downlink and an uplink. The downlink transmitted signal is received by the destination control station 20 or ground station 30 (31 to 3N). Note that vehicle-to-vehicle station communication and base station-to-base station communication can also be performed via the satellite 100. However, before the communication line is established, it is necessary to perform an uplink access test (UAT) of the vehicle-mounted station 10. The following describes a technique that can automate this procedure.

[0014] Fig. 2 is a block diagram showing an example of the vehicle-mounted station 10 shown in Fig. 1. The vehicle-mounted station 10, which is an example of a mobile station device, includes an antenna 11 that can be mounted on a vehicle and an in-vehicle unit 13 that can be connected to the antenna 11 via a cable 12. The antenna 11 is a phased array antenna whose beam direction can be electronically controlled. The polarization direction of the beam can be controlled by rotating the antenna 11, for example, around a normal to the antenna aperture as the rotation axis.

[0015] The vehicle-mounted unit 13 includes a high power converter (HPC) 22, a low noise converter (LNC) 23, a modem unit 24, and a processor 25.

[0016] The modem unit 24 modulates a carrier wave with a transmission signal from an application device 14 (such as a video encoder, video decoder, or IP transmitter) to generate and output a transmission signal for the satellite. The transmission signal includes video, audio, and data materials encoded using encoding methods such as MPEG2-TS (Moving Picture Experts Group 2 - Transport Stream) and H.265 / HEVC (High Efficiency Video Coding). The modem unit 24 generates a transmission signal by modulating a Ku-band carrier wave using, for example, N-APSK (Amplitude Phase Shift Keying). N is typically 16, 32, or 64, but other modulation methods with a multi-level N are also possible. Modulation methods such as QAM (Quadrature Amplitude Modulation) and QPSK (Quadrature Phase Shift Keying) can also be used.

[0017] The HPC 22 amplifies the power of this transmission signal, which is then uplink transmitted via a cable 12 and an antenna 11 to the target satellite. On the other hand, the downlink signal from the target satellite is subjected to low-noise amplification by the LNC 23 , demodulated by the modem 24 , and sent to the application device 14 .

[0018] The position sensor 15, the operation unit 16, and the display unit 17 are connected to the processor 25. The position sensor 15 is a positioning sensor that uses, for example, a GPS (Global Positioning System), and acquires position information and notifies the processor 25 of the position information.

[0019] The operation unit 16 includes, for example, a power button for the vehicle-mounted station 10, a capture button for starting the satellite capture process, etc. The display unit 17 is, for example, an LCD (Liquid Crystal Display) panel provided on the operation unit 16, and displays the results and status of the satellite capture process, the UAT results, etc.

[0020] The processor 25 is hardware that mainly includes a CPU (Central Processing Unit) and executes arithmetic processing according to a program stored in a memory. The hardware and software as a program work together to realize the functions according to the embodiment. In other words, the processor 25, the in-vehicle unit 13, and the in-vehicle station 10 are a computer that realizes functions through the cooperative operation of the software and hardware.

[0021] The processor 25 includes, for example, an acquisition control unit 25a, a test request unit 25b, and a transmission control unit 25c as control functions implemented by built-in software. The acquisition control unit 25a controls the direction and polarization of the beam of the antenna 11 to acquire the target satellite. Prior to establishing a communication link, the test request unit 25b transmits to the control station 20 a test request message requesting the performance of a test related to uplink communication with the satellite 100. In an embodiment, the test request unit 25b transmits a UAT request message to request the performance of UAT. When the control station 20 accepts the UAT request, the transmission control unit 25c transmits a test carrier signal toward the satellite 100.

[0022] Fig. 3 is a functional block diagram showing an example of the control station 20 shown in Fig. 1. The control station 20 includes an operation terminal 41, an orderwire modem 42, an adapter 43, an edge controller 44, a processor 45, an edge controller 46, a spectrum analyzer 47, and a spectrum analyzer 48. In the embodiment, these are assumed to be computers each having a CPU (Central Processing Unit), and to be connected via a LAN (Local Area Network).

[0023] The operation terminal 41 is connected to the processor 45 and inputs various commands to the system. For example, when a UAT request or XPD measurement is manually performed by an operator, a GUI (Graphical User Interface) on the operation terminal 41 is used.

[0024] The orderwire modem 42 connects voice communication (orderwire) channels between the control station 20 and other stations, and controls connection settings for a CSC (Common Signaling Channel) line passing through the satellite 100. The orderwire modem 42 is connected to an edge controller 44. An adapter 43 is provided between the orderwire modem 42 and the edge controller 44 as a buffer for ensuring reliable transmission and reception of CSC messages.

[0025] The edge controller 44 relays communication between the processor 45 and the orderwire modem 42. If a UAT request message is included in a signal received from the orderwire modem 42 via the CSC, the edge controller 44 notifies the processor 45 of this UAT request message. The processor 45 is connected to spectrum analyzers 47 and 48 via an edge controller 46. The edge controller 46 and the spectrum analyzers 47 and 48 function as a measurement unit. The spectrum analyzers 47 and 48 measure the level of the test carrier signal transmitted from the vehicle-mounted station 10 to the satellite 100 by performing a spectrum analysis of the signal arriving via downlink from the satellite 100.

[0026] That is, the spectrum analyzer 47 analyzes the spectrum of the main polarization side of the test carrier signal that arrives via downlink from the vehicle-mounted station 10 that sent the UAT request message via the satellite 100. The spectrum analyzer 48 analyzes the spectrum of the reverse polarization side of the test carrier signal. Based on these measurement values, a measurement value of the cross polarization discrimination of the test carrier signal is obtained.

[0027] The processor 45 includes a determination unit 45a and a notification unit 45b as processing functions according to the embodiment. The determining unit 45a determines the result of the UAT based on the measured value of the cross polarization discrimination of the test carrier signal. The notification unit 45b generates information for the processor 45 to notify the requesting vehicle-mounted station 10 of the UAT result, and notifies the requesting vehicle-mounted station 10 of the UAT result.

[0028] <effect> Next, the operation of the above configuration will be described. 4 is a sequence diagram showing an example of a processing procedure according to the first embodiment. After arriving at the site and completing initial procedures such as jacking and satellite capture processing, the vehicle-mounted station 10 starts establishing a communication line via the satellite 100. Prior to this, the vehicle-mounted station 10 transmits a UAT request message to the control station 20 via the CSC line to request the execution of a UAT test. The CSC line is a low-level signal that is permitted to be transmitted before the satellite is established. The processor 45 of the control station 20 then determines whether the execution of the UAT test can be accepted without multiple requests or interference from other stations, and if possible, returns an OK message to the requesting vehicle-mounted station 10.

[0029] Upon receiving this, the vehicle-mounted station 10 transmits an unmodulated, low-level test carrier signal via uplink to the satellite 100 (step S1). This test carrier signal reaches the control station 20 via downlink.

[0030] Meanwhile, the UAT request message is sent to the edge controller 46 of the control station 20, and the edge controller 46 starts XPD measurement control by the spectrum analyzers 47 and 48. The edge controller 46 uses the spectrum analyzer 47 to measure the carrier level and noise level of the main polarization side of the test carrier signal (step S2). The edge controller 46 acquires these measured values ​​and calculates the ratio of the carrier level to the noise level (C / N). The edge controller 46 also uses the spectrum analyzer 48 to measure the carrier level and noise level of the reverse polarization side of the test carrier signal (step S3). The edge controller 46 acquires these measured values ​​and calculates the ratio of the carrier level to the noise level (C / N). Here, the level measurements by the spectrum analyzers 47 and 48 may be performed asynchronously.

[0031] The edge controller 46 calculates the cross polarization discrimination of the test carrier signal from the C / N measurement values ​​of the main polarization and the reverse polarization, and transmits the calculated value to the processor 45 (step S4). The processor 45 then determines the test result by determining whether these measurement values ​​meet the pass / fail criteria (step S5). The processor 45 then notifies the test result to the vehicle-mounted station 10 that requested the UAT (step S6).

[0032] 5 and 6 are diagrams showing examples of GUI screens displayed on the display unit 17 of the vehicle-mounted station 10. In FIG. 5, when the UAT button (a) is tapped or clicked with the mouse, a UAT request is issued and UAT is in progress. The message window (b) displays the status of the CSC line one by one, scrolling down each time an event occurs. The level indicator (c) displays the strength of the CSC carrier being received, for example, on a 10-point scale. FIG. 6 shows a state in which seven symbols are extended, indicating relatively good reception conditions.

[0033] In Figure 6, the level indicator (c) shows only one symbol, indicating that the reception condition has deteriorated. In response, the message window (b) immediately displays the message "CSC line disconnected." Although the strength of the signals transmitted via satellite 100 fluctuates depending on factors such as weather, CSC is primarily used to transmit control signals, and since it is a narrowband, low-rate line, it is relatively resistant to external factors. Even if the CSC line is disconnected, it will quickly recover.

[0034] The CSC uplink carrier can only be turned on when the CSC downlink carrier is being received normally. When the CSC uplink carrier is turned on, the CSC icon (d) lights up in a conspicuous color. Also, the level indicator (c) will be displayed in green, for example, if the CSC downlink carrier is being received normally, and in red, for example, if not. In addition, the name of the captured satellite, the name of the control station, etc. may also be displayed.

[0035] <Effects> According to the first embodiment, when a UAT request message is sent from the vehicle-mounted station 10, this triggers an automatic execution of a sequence from XPD measurement to notification of the result. That is, by tapping the UAT button (a) in Figures 5 and 6, the UAT request, XPD value measurement by the control station 20, pass / fail judgment, and notification of the result to the vehicle-mounted station 10 are fully automated. This minimizes the operations required of the operator, dramatically reducing the burden on the operator.

[0036] Furthermore, in the first embodiment, the UAT request message is transmitted from the vehicle-mounted station 10 to the control station 20 using a CSC line. This makes it possible to request UAT with minimal resource consumption and to perform UAT in a rational procedure.

[0037] From these points, according to the first embodiment, a satellite communication system that aims to reduce the human load involved in the uplink access test is provided. 、It is possible to provide a control station device and a control method, and ultimately to provide a technology that stabilizes the quality of uplink access tests through automation and prevents variations in results.

[0038] [Second embodiment] In the second embodiment, a form relating to a UAT request and XPD measurement during site diversity operation will be disclosed.

[0039] <Configuration> Fig. 7 is a diagram showing an example of a satellite communication system according to the second embodiment. The satellite communication system shown in Fig. 7 includes a control station 20 and a sub-control station 50 that cooperates with the control station 20 to realize site diversity operation. The control station 20 and the sub-control station 50 belong to a satellite network 300 and can communicate with a ground station via a satellite 100.

[0040] Here, the control station 20 and the sub control station 50 can also communicate with each other via the terrestrial network 200. That is, the control station 20 is connected to the terrestrial network 200 via a router 201, and the sub control station 50 is connected to the terrestrial network 200 via a router 202, and RF (Radio Frequency) signals for satellite transmission can be exchanged between them via the terrestrial network 200. The terrestrial network 200 is, for example, an ultra-high speed communication network that has an IP (Internet Protocol) interface and is capable of exchanging SDI (Serial Digital Interface) signals, and is realized as an optical fiber network dedicated to a broadcasting company, or the like.

[0041] As shown in Figure 7, if there are clouds or rainfall above the control station 20, the communication link between the control station 20 and the satellite 100 is physically blocked, preventing the uplink signal from the control station 20 from reaching the satellite 100 at a sufficient level. In recent satellite communication systems, multilevel amplitude-phase modulation (AMPS) such as 64APSK and 32APSK is widely used to meet the needs for high image quality, high compression, and narrowband transmission. This makes the systems vulnerable to sudden fluctuations in reception level. Additionally, the recent increase in the severity of weather (so-called torrential rain) has increased the likelihood of block noise and short interruptions. It is a high priority to prevent noise from mixing into news material on SNG.

[0042] Site diversity is an effective way to deal with such events and as a BCP (Business Continuity Plan) measure in the event of a major disaster. In Fig. 7, for example, broadcast radio waves (RF signals) from control station 20 can be transmitted to secondary control station 50 via terrestrial network 200, and the secondary control station 50's equipment can be used to transmit the carrier of control station 20 to satellite 100 and maintain control functions. Even when using such site diversity functions for control, automation of operations is required. Details of this are explained below.

[0043] Fig. 8 is a functional block diagram showing an example of the control station 20 and the sub control station 50 shown in Fig. 7. In Fig. 8, the control station 20 and the sub control station 50 are connected to a ground network 200. The sub-control station 50 includes an operation terminal 51, an orderwire modem 52, an adapter 53, an edge controller 54, a processor 55, an edge controller 56, and spectrum analyzers 57 and 58. These have the same functions as the corresponding functional blocks in the control station 20, and are communicably connected via a LAN in the sub-control station 50. The processor 55 also includes a determination unit 56a and a notification unit 56b that correspond to those in the control station 20.

[0044] The processor 45 of the control station 20 includes a transfer control unit 45ac as a processing function according to the second embodiment. When receiving a UAT request, the transfer control unit 45c determines whether site diversity is in operation. If site diversity is not in operation, the transfer control unit 45c issues an XPD measurement instruction to the edge controller 46 in its own station. On the other hand, if site diversity is in operation, the transfer control unit 45c issues an XPD measurement instruction to the edge controller 56 of the sub-control station 50.

[0045] <effect> Next, the operation of the above configuration will be described. 9 is a sequence diagram showing an example of a processing procedure according to the second embodiment. In FIG. 9, the vehicle-mounted station 10, which has completed the initial procedure, transmits a UAT request message to the control station 20 via the CSC line. The processor 45 of the control station 20 then determines whether site diversity is in operation at that time (step S10). If site diversity is not in operation (No), the UAT request message from the vehicle-mounted station 10 is passed to the edge controller 46 of the control station, and XPD measurement is performed according to the same sequence as in FIG. 4.

[0046] On the other hand, if site diversity operation is in progress (YES), the processor 45 transfers the UAT request message to the edge controller 56 of the secondary control station 50 via the terrestrial network 200 (step S11). In response to this, the edge controller 56 starts XPD measurement control using the spectrum analyzers 57 and 58. The spectrum analyzer 57 measures the carrier level and noise level of the main polarization side of the test carrier signal that arrived at its own station (secondary control station 50) via downlink (step S21). The edge controller 56 acquires these measurements and calculates the ratio of the carrier level to the noise level (C / N). The spectrum analyzer 58 measures the carrier level and noise level of the reverse polarization side of the test carrier signal (step S22). The edge controller 56 acquires these measurements and calculates the ratio of the carrier level to the noise level (C / N). The level measurements by the spectrum analyzers 57 and 58 may be performed asynchronously.

[0047] The edge controller 56 calculates the cross polarization discrimination of the test carrier signal from the C / N measurement value of the main polarization and the C / N measurement value of the reverse polarization, and returns the calculated value to the processor 45 of the control station 20 via the terrestrial network 200 (step S23). The processor 45 then determines the test result by determining whether these measurement values ​​satisfy the pass / fail criteria (step S5), and notifies the vehicle-mounted station 10 of the test result (step S6).

[0048] In the above sequence, the display unit 17 of the vehicle-mounted station 10 displays the same information as in Figures 5 and 6, and the operator does not need to be aware of whether the XPD measurement is being performed by the control station 20 or the sub-control station 50.

[0049] <Effects> According to the second embodiment, when a UAT request message is sent from the vehicle-mounted station 10, the system determines whether or not site diversity is in operation. If site diversity is not in operation, XPD measurement is performed in the own station (control station 20) that received the UAT request message, and the result is obtained.

[0050] On the other hand, if site diversity is in operation, the UAT request message is transferred from the local station (control station 20) to the sub station (sub control station 50), and the sub station performs XPD measurement remotely (remote XPD measurement). The result is returned to the local station and notified to the requesting vehicle station 10. During this time, the operator of the vehicle station 10 does not need to be aware of whether the XPD measurement is being performed by the control station 20 or the sub control station 50. In other words, UAT can be performed fully automatically and seamlessly regardless of whether site diversity is in operation.

[0051] From these facts, the second embodiment also provides a satellite communication system that reduces the human load involved in the uplink access test. 、 It is possible to provide a control station device and a control method.

[0052] It should be noted that the present invention is not limited to the above-described embodiment. For example, in the first embodiment, the orderwire modem 42, edge controllers 44 and 46, processor 45, and the like may be realized as software functions implemented on a common server. Also, although the UAT request message is transmitted to the control station 20 using a CSC line, the present invention is not limited to this. For example, a communication means of the ground network 200 may be used. In short, it is sufficient if a trigger for performing XPD measurement can be given to the control station 20 by some means.

[0053] Furthermore, various modes can be considered for the exclusive control when UAT request messages from multiple vehicle-mounted stations 10 reach the control station 20. For example, the priority of UAT and XPD measurements may be variably controlled depending on the attributes and importance of the video content to be transmitted. Alternatively, whether the vehicle-mounted station 10 belongs to a key station or an affiliated station may also be a criterion for determining exclusive control. Such modes can be realized by providing a processing block (exclusion control unit) that performs the above-mentioned exclusive control in, for example, the processor 45.

[0054] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0055] 10...vehicle-mounted station, 11...antenna, 12...cable, 13...vehicle-mounted unit, 14...application device, 15...position sensor, 16...operation unit, 17...display unit, 20...control station, 24...modulation / demodulation unit, 25...processor, 25a...acquisition control unit, 25b...test request unit, 25c...transmission control unit, 30...ground station, 41...operation terminal, 42...orderwire modem, 43...adapter, 44...edge controller, 45...processor, 45a...determination unit, 45b...notification unit, 45c...transfer control unit, 46...edge controller, 47, 48...spectrum analyzer, 50...sub-control station, 51...operation terminal, 52...orderwire modem, 53...adapter, 54...edge controller, 55...processor, 56...edge controller, 55a...determination unit, 55b...notification unit, 57, 58...spectrum analyzer, 100...satellite, 200...terrestrial network, 201, 202...routers, 300...satellite network.

Claims

1. a control station device that controls the satellite in orbit; a mobile station device that establishes a line via the satellite and communicates with a ground station; The mobile station device a test request unit that transmits a test request message to the control station device, requesting the execution of a test related to uplink communication with the satellite, prior to the establishment of the line; a transmission control unit that transmits a test carrier signal toward the satellite when the request is accepted; The control station device a measurement unit that measures the cross polarization discrimination of the test carrier signal that arrives in a downlink from the mobile station device that transmitted the test request message via the satellite to obtain a measurement value; a determination unit that determines the result of the test based on the measurement value; a notification unit that notifies the mobile station device of a result of the test; an exclusive control unit that, when the test request messages arrive from a plurality of mobile stations, performs exclusive control based on predetermined criteria and determines the priority of the implementation of the tests related to the uplink communication.

2. a control station device that controls the satellite in orbit; a mobile station device that establishes a line via the satellite and communicates with a ground station; a sub-control station device that cooperates with the control station device to realize site diversity operation, The mobile station device a test request unit that transmits a test request message to the control station device, requesting the execution of a test related to uplink communication with the satellite, prior to the establishment of the line; a transmission control unit that transmits a test carrier signal toward the satellite when the request is accepted; The control station device and the sub control station device, a measurement unit that measures the cross polarization discrimination of the test carrier signal that arrives in a downlink from the mobile station device that transmitted the test request message via the satellite to obtain a measurement value; a determination unit that determines the result of the test based on the measurement value; a notification unit that notifies the mobile station device of a result of the test; an exclusive control unit that performs exclusive control based on a predetermined determination criterion when the test request messages arrive from a plurality of mobile stations, and determines a priority order for performing the tests related to the uplink communication; Furthermore, the control station device A satellite communication system comprising a transfer control unit that passes the test request message to a measurement unit of the local station device if site diversity operation is not in progress, and transfers the test request message to the measurement unit of the secondary control station device if site diversity operation is in progress.

3. the test request unit transmits the test request message using a Common Signaling Channel (CSC) via the satellite; 3. The satellite communication system according to claim 1, wherein the measurement unit measures the cross polarization discrimination of a test carrier signal arriving via a downlink from a mobile station device that transmitted the test request message using the CSC.

4. The measurement unit a first spectrum analyzer for analyzing a spectrum of a main polarization of a test carrier signal arriving on the downlink; 3. A satellite communication system according to claim 1, further comprising a second spectrum analyzer for analyzing a spectrum relating to the opposite polarization of the test carrier signal arriving on the downlink.

5. A satellite communication system as described in either claim 1 or 2, wherein the exclusive control unit variably controls the priority depending on the attributes of the video content that the mobile station intends to transmit or the importance of the video content.

6. A satellite communication system as described in either claim 1 or 2, wherein the exclusive control unit variably controls the priority depending on whether the mobile station belongs to a key station or an affiliated station.

7. A control station device for controlling an orbiting satellite, a measurement unit that, when receiving a test request message from a mobile station device that establishes a line via the satellite and communicates with a ground station, requests execution of a test related to uplink communication with the satellite prior to establishment of the line, measures the cross polarization discrimination of a test carrier signal that arrives in a downlink via the satellite from the mobile station device that transmitted the test request message, thereby obtaining a measurement value; a determination unit that determines the result of the test based on the measurement value; a notification unit that notifies the mobile station device of a result of the test; and an exclusive control unit that, when the test request messages arrive from a plurality of mobile stations, performs exclusive control based on predetermined criteria and determines the priority of the implementation of tests related to the uplink communication.

8. A control station device as described in claim 7, further comprising a transfer control unit that transfers the test request message to a secondary control station device that works in cooperation with its own station device to realize site diversity operation when the site diversity operation is in progress.

9. A control method for a satellite communication system having a control station device that controls an orbiting satellite and a mobile station device that establishes a line via the satellite and communicates with a ground station, comprising: the mobile station device transmitting a test request message to the control station device, requesting the execution of a test related to uplink communication with the satellite, prior to the establishment of the line; If the request is accepted, the mobile station device transmits a test carrier signal toward the satellite; and the control station device measures a cross polarization discrimination of the test carrier signal that arrives in a downlink from the mobile station device that transmitted the test request message via the satellite to obtain a measurement value; the control station device determining a result of the test based on the measurement values; the control station device notifying the mobile station device of a result of the test; and when the test request messages arrive from a plurality of mobile stations, the control station device performs exclusive control based on predetermined criteria and determines the priority of the implementation of tests related to the uplink communication.

Images