JP2003188785A - Successive transmission control system for satellite communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the deterioration of a line quality when a communication or broadcasting radio wave is attenuated by a local weather in each of service areas, in particular to prevent the deterioration of the line quality when transmission power for compensating the attenuation of the communication or broadcasting radio wave cannot be secured. <P>SOLUTION: In a satellite communication system, pieces of weather information Sa, Sb and Sc in a plurality of service areas A, B and C collected by a local weather information collection and distributing institution 1 are sent to an arithmetic/successive transmission controller 10 as weather information Sd. The arithmetic/successive transmission controller 10 sets the number of times of successive transmission for compensating the attenuation caused by rainfall based on the amount of rainfall and the attenuation of a signal strength is compensated/corrected by controlling the successive transmission from a satellite 3 to the service area in a satellite control station 3 to achieve the number of times of successive transmission. Besides, the time interval of succession transmission is set and controlled corresponding to situations. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite communication system which communicates or broadcasts to a plurality of service areas via satellites and is used for compensation / correction of signal strength attenuation due to local weather information of each service area. It is related to the method.

[0002]

2. Description of the Related Art In a conventional satellite communication system, in satellite communication or satellite broadcasting, a rainfall attenuation amount, which is one of radio wave interference amount information leading to radio wave attenuation of communication or broadcasting, is estimated in advance by a statistical method, and a target value is calculated. Radio waves of a certain intensity, which allows for an estimated value of rainfall attenuation that satisfies the line availability, are emitted from the satellite to the earth station or from the earth station to the satellite. It is called a rainfall margin to have a margin in consideration of this rainfall attenuation amount. Conventional communication / broadcasting satellites, which expect a rainfall margin of a fixed fixed amount of radio interference to ensure the quality of communication or broadcasting, are based on the estimated values, so the actual rainfall is estimated to be large. Due to the fact that there are areas where rainfall attenuation cannot be compensated for by the rainfall margin due to the above, and there are areas where the rainfall margin is not necessary due to fine weather, the satellite's limited electric power was not used effectively.

Therefore, without using the estimated value of rainfall attenuation,
Japanese Patent Application Laid-Open No. 5-41683 discloses a satellite communication system in which electric power is controlled by actual rainfall. Figure 5
FIG. 1 is a configuration diagram showing a conventional satellite communication / broadcasting power control system disclosed in Japanese Patent Laid-Open No. 5-41683. In the figure, A, B, and C are a plurality of service areas that receive communication or broadcast waves, for example, three service areas, Sa, Sb, and Sc are regional weather information such as rainfall in the service areas A, B, and C, and Sd is each. All weather information S, Sb, Sc that collects local weather information Sa, Sb, Sc from service areas A, B, C
1 is transmission power control information, 1 is local weather information collection and distribution organization, 2 is arithmetic unit, 3 is satellite control station, 4 is satellite, 5 is multi-beam antenna, T1 is transmission power control information S1 is transmitted to satellite 4. Radio waves Ta, Tb, and Tc are communication radio waves or broadcast radio waves for a plurality of communication or broadcasting service areas A, B, and C, respectively. Here, of the total amount of transmission power supplied to the antenna in the satellite, each service area A,
The transmission powers corresponding to the expected rainfall margins for B and C are set in advance. The total transmission power corresponding to the rainfall margin set for each service area in all service areas is used as the rain attenuation compensation transmission power.

Next, the operation will be described. The local weather information Sa, Sb, Sc of each service area A, B, C is sent immediately or intermittently as the weather information Sd of each service area A, B, C via the local weather information collection and distribution organization 1. Input to the arithmetic unit 2. The arithmetic unit 2 guides the information for distributing and distributing the rain attenuation compensation transmission power to the service areas A, B, C, that is, the transmission power control information S1 based on the all weather information Sd. At this time, the transmission power for rain attenuation compensation is preferentially distributed to the service areas A, B, and C where the deterioration of the line quality due to rainfall is predicted to be larger. The transmission power control information S1 obtained by the arithmetic unit 2 is transmitted to the satellite 4 as a radio wave T1 for transmitting the transmission power control information via the satellite control station 3. The satellite 4 uses each of the service areas A, based on the transmission power control information S1 transmitted by the radio wave T1.
The transmission power for B and C is controlled, and the communication radio waves or broadcast radio waves Ta, Tb, Tc for each service area are radiated from the multi-beam antenna 5.

[0005]

Since the conventional configuration is as described above, if the amount of rainfall is too large, the limit of the transmission power for rainfall attenuation compensation may be exceeded. As described above, when the amount of rainfall attenuation due to the increase in rainfall cannot be compensated by increasing the transmission power, there is a problem that the line quality deteriorates, the signal strength is attenuated, and information is lost.

The present invention has been made in order to solve the above problems, and even when the amount of rainfall exceeds the limit of the transmission power for rainfall attenuation compensation, the signal strength attenuation is compensated to provide information in the service area. It is an object of the present invention to obtain a continuous transmission control system of a satellite communication system which can be delivered to the satellite with high reliability.

[0007]

A continuous transmission control system for a satellite communication system according to the present invention, when communicating or broadcasting to a plurality of service areas via a satellite, results in attenuation of the communication or broadcasting radio waves. Continuous transmission number setting means for setting the number of continuous transmissions to each of the service areas based on the radio disturbance amount information related to the local weather, and from the satellite to each of the service areas so that the set number of continuous transmissions is achieved. And a continuous feed number control means for controlling the continuous feed number.

Further, in the continuous transmission control method of the satellite communication system according to the present invention, the radio wave interference amount information relating to the local weather is the rainfall amount, and the continuous transmission number setting means for each of the service areas When it is not possible to secure the transmission power for compensating the amount of rainfall attenuation due to the amount of rainfall in the region, the number of continuous transmissions is set so as to compensate for the amount of rainfall attenuation.

Further, in the continuous transmission control system of the satellite communication system according to the present invention, the radio disturbance amount information relating to the local weather is the amount of rainfall, and the continuous transmission number setting means sets the number of times for each service area. The transmission power and the number of continuous transmissions are set so as to compensate for the rainfall attenuation due to the rainfall in the area, and the transmission power from the satellite to each service area is set to the set transmission power. It is characterized by.

Further, the continuous transmission control method of the satellite communication system according to the present invention is characterized in that continuous transmission interval setting means for setting a continuous transmission time interval and each of the satellites are arranged so that the set continuous transmission interval is reached. It is characterized in that it is provided with a continuous transmission interval control means for controlling the continuous transmission interval to the service area.

Further, the continuous transmission interval setting means in the continuous transmission control system of the satellite communication system according to the present invention is characterized in that the continuous transmission time interval is set based on the wind speed of the regional weather. .

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. 1 is a configuration diagram showing a main part of a satellite communication system according to a first embodiment of the present invention. In the figure, A, B, and C are a plurality of service areas that receive communication or broadcast waves, for example, three service areas, S
a, Sb, Sc are local weather information of each service area A, B, C, Sd is all weather information gathering the local weather information Sa, Sb, Sc from each service area A, B, C, S10 is Transmission power of each service area A, B, C
Transmission control information, 1 is local weather information collection and distribution agency, 3
Is a satellite control station, 4 is a satellite, 5 is a multi-beam antenna,
Reference numeral 10 is a calculation / continuous transmission control device, T1 is a radio wave for transmitting the transmission power control information for each service area A, B, C of the transmission power / continuous transmission control information S10 to the satellite 4, Ta, Tb, Tc.
Is a communication radio wave or a broadcast radio wave for each of a plurality of communication or broadcasting service areas A, B, and C. Further, FIG. 2 is a graph for explaining the continuous feed control method according to this embodiment, in which the horizontal axis represents rainfall (mm / h) and the vertical axis represents the number of continuous feeds (times).

When communicating or broadcasting to a plurality of service areas via a satellite, signal strength attenuation of communication or broadcasting radio waves occurs due to radio wave disturbance related to local weather in each service area. In this embodiment, for example, the amount of rainfall in local weather is the amount of radio interference that causes attenuation of communication or broadcast radio waves. Therefore, the signal strength attenuation to each service area A, B, C is calculated based on the rainfall information of the local weather of each service area A, B, C, and the antenna in the satellite is calculated according to this signal strength attenuation. The total amount of transmitted power of
It is controlled to compensate or correct the signal strength attenuation.

Next, the operation of this embodiment will be described. In FIG. 1, the local weather information Sa, Sb, Sc of each service area A, B, C passes through the local weather information collection and distribution organization 1, and all the weather information gathered of each service area A, B, C. It is input to the calculation / continuous transfer control device 10 as Sd immediately or intermittently. Arithmetic / continuous transfer control device 10
Creates information for allocating the transmission power for rainfall attenuation compensation to each service area A, B, C based on the total weather information Sd. That is, the total amount of transmission power supplied to the antennas in the satellite has a transmission power corresponding to a margin (rainfall margin) given in consideration of the amount of rainfall attenuation in each service area A, B, and C. Part or all shall be the transmission power for rain attenuation compensation for all service areas. Arithmetic / continuous transfer control device 1
By 0, information for preferentially distributing and distributing the rain attenuation compensation transmission power to the service areas A, B, and C where the deterioration of the line quality due to rainfall is predicted, that is, the transmission power control information is derived. When the transmission power that can compensate for the rain attenuation in all service areas can be secured, the continuous transmission control information is created by setting the number of continuous transmissions in each service area to one.

Next, a case will be described in which the amount of rainfall in any one or a plurality of service areas is large and the transmission power for compensating for the amount of rainfall attenuation in all service areas cannot be secured by the transmission power for rainfall attenuation compensation. When creating the information for allocating the transmission power for rain attenuation compensation to each service area A, B, C based on the rainfall information of the total weather information Sd, for example, it corresponds to the rainfall margin in order from the service area with the smallest rainfall amount. Transmission power to be distributed. The number of continuous transmissions is set to 1 for an area in which the transmission power for compensating for the amount of rainfall attenuation can be secured among the plurality of service areas.
Further, for a service area in which a transmission power for compensating for the rain attenuation amount cannot be secured among a plurality of service areas, as shown in FIG. Control information. The transmission power control information of this service area may be the reference value of the transmission power, or the transmission power for rain attenuation compensation may be set to the transmission power by adding the reference value to it.

The information thus set is transmitted to the satellite control station 3 as transmission power / continuous transmission control information S10. The satellite control station 3 performs continuous transmission control based on the continuous transmission control information. The transmission power control information is transmitted to the satellite 4 as a radio wave T1, and the satellite 4 transmits the transmission power control information by the radio wave T1. Based on the above, the transmission power for each service area A, B, C is controlled, and the communication wave or broadcast wave Ta, Tb, Tc for each service area is provided by the multi-beam antenna 5.
Radiate from.

As shown in FIG. 2, the continuous transmission control initially compensates for the rain attenuation by increasing the transmission power by setting the number of continuous transmissions to 1 as the rainfall increases. If it becomes impossible to secure transmission power that compensates for the amount of attenuation, the number of continuous transmissions will be increased to 2 or 3.

Further, not only the number of continuous transmissions is increased according to the amount of rainfall, but also the number of continuous transmissions can be set in consideration of the importance of the information to be transmitted. That is, the error rate at the rainfall rate x is α, and the error allowable rate is β, and the number of continuous transmissions y is set to satisfy the following equation. α ^y <β where x means rainfall rate (mm / h) and error rate α =
BER (Bit Error Rate), and error tolerance rate β = B
It is an allowable limit value of ER. The error rate when the rainfall rate is x is α
If the error allowable rate is β and is stored in the calculation / continuous transfer control device 10 in advance, the continuous transmission number y can be set by calculating the rainfall rate x from the total rainfall amount information Sd. If the error tolerance β in the above formula is set according to the importance of information, etc., the number of continuous transmissions y also changes according to the importance of information, rain attenuation can be compensated, and particularly important information can be ensured. Can be communicated to.

In the continuous transmission control based on FIG. 2 described above, rain attenuation is compensated by increasing the transmission power when the number of continuous transmissions is one, and when the number of continuous transmissions is two or more, the amount of rainfall increases. On the other hand, the transmission power is constant. On the other hand, the transmission power may be changed in consideration of rain attenuation even when the number of continuous transmissions is two or more. By changing the transmission power even when the number of consecutive transmissions is two or more, it is possible to set the transmission power and the number of consecutive transmissions more suitable for rain attenuation, so that it is possible to reliably transmit information and save transmission power. be able to.

Further, when the transmission power / continuous transmission control information S10 is created by the arithmetic / continuous transmission control device 10, it may be set as shown in FIG. FIG. 3 shows continuous transmission control in one service area, in which the horizontal axis represents rainfall (mm / h) and the vertical axis represents the number of continuous transmissions and transmission power. The solid line in the graph represents the number of continuous transmissions, and the dotted line represents the transmission power. The maximum value of transmission power is a predetermined transmission power that can be secured in this service area. Using the graph shown in FIG. 3, the number of continuous transmissions and the transmission power, which are the values on the y-axis, are determined from the values on the x-axis at a certain amount of rainfall. With this control method, if the transmission power for compensating the rainfall attenuation in all service areas cannot be secured by the transmission power for rainfall attenuation compensation, the number of consecutive transmissions is not increased, but it is optimal according to the amount of rainfall at that time in a certain area. Set the appropriate transmission power and the number of continuous transmissions. For this reason, it is possible to set the transmission power and the number of consecutive transmissions more suitable for rain attenuation, so that it is possible to reliably transmit information and save the transmission power.

As the radio interference amount information of the local meteorological information Sa, Sb, Sc and the meteorological information Sd, one hourly hourly precipitation of AMeDAS (AMeDAS) provided by the Meteorological Agency, radar AMeDAS synthetic precipitation, and precipitation amount Short-term forecasts are possible. The local meteorological information collecting and distributing organization 1 may be the Meteorological Agency, the Japan Meteorological Association, a private weather information company, or the like. In addition to the amount of rainfall, the amount of radio interference related to the meteorological information Sd may be snowfall, wind power, temperature, humidity, thick fog, lightning strike, etc. By setting the number of continuous transmissions and performing continuous transmission, it is possible to obtain a satellite communication system capable of preventing line deterioration.

Embodiment 2. FIG. 4 is a graph for explaining a continuous transmission control system of a satellite communication system according to a second embodiment of the present invention, showing time interval control of continuous transmission in one service area, where the horizontal axis indicates wind speed (km / h). ), The vertical axis indicates the continuous feeding interval (minutes). In the first embodiment, when performing continuous feed control, the continuous feed was performed continuously without taking a time interval, but in the present embodiment, the continuous feed time interval is set,
It is controlled so that the sheets are sent for a predetermined period of time and then continuously sent. Here, the configuration of the satellite communication system and the setting of the number of continuous transmissions are the same as those in the first embodiment.

For example, even if the number of continuous transmissions is set by the arithmetic / continuous transmission control device 10 of the first embodiment so as to compensate for rain attenuation, if the wind speed is slow, the rain cloud is stagnant and the transmission is repeated many times. But the same can happen. In such a case, in order to carry out continuous transmission after the rain clouds move, in this embodiment, the time interval is set based on the wind speed. That is, as shown in FIG. 4, when the wind speed is slow, the continuous feeding interval is set long. On the other hand, when the wind speed is fast, the rain clouds move quickly, so even if you send them continuously, there are actually multiple receiving stations in the service area, and information is sent to different receiving stations in the service area from the last time. Can be delivered. Therefore, the continuous feeding interval is set shorter as the wind speed increases. The wind speed of each service area at this time is included in the weather information Sa, Sb, Sc of each service area A, B, C collected by the local weather information collection and distribution organization 1 as shown in FIG. It should be included in the meteorological information Sd, which is a collection of regional meteorological information of a plurality of service areas sent to the arithmetic / continuous transfer control device 10. The information on the continuous transmission time interval set in this manner is transmitted to the satellite control station 3 as transmission power / continuous transmission control information S10. In the satellite control station 3, the continuous transmission interval control is executed based on the continuous transmission interval control information. As described above, in the calculation / continuous transmission control device 10, by changing the continuous transmission interval according to the situation, information can be transmitted reliably and the reliability of the satellite communication system can be improved.

Although the continuous transmission interval is changed according to the wind speed in the above, the continuous transmission time interval may be set longer in a time zone when communication radio waves are crowded. Alternatively, for example, the communication status may be detected at regular time intervals, and the transmission may be performed when the crowded state of radio waves is resolved. In the above, the number of service areas is three, A, B, and C, but the number is not limited to this.

[0025]

As described above, according to the present invention, when communicating or broadcasting to a plurality of service areas via satellites, radio waves relating to the local weather of each of the service areas, which leads to attenuation of the communication or broadcasting radio waves, are obtained. Continuous transmission number setting means for setting the number of continuous transmissions to each of the service areas based on the failure amount information, and controlling the number of continuous transmissions from the satellite to each of the service areas so that the set number of continuous transmissions is achieved. By providing the continuous transmission number control means, it is possible to obtain a control system for a satellite communication system that can reliably deliver information to a service area even when the attenuation of radio waves cannot be compensated by the transmission power.

The radio disturbance amount information relating to the local weather is rainfall information of the local weather, and the continuous transmission number setting means gives the rain attenuation amount due to the rainfall amount of the area to each service area. A satellite communication system that can reliably deliver information to a service area even when rain attenuation cannot be compensated by transmission power by setting the number of consecutive transmissions to compensate for the rain attenuation when the transmission power to be compensated cannot be secured Can be obtained.

Further, the radio disturbance amount information relating to the local weather is the rainfall amount of the local weather, and the continuous transmission number setting means is
For each of the service areas, a transmission power and a number of consecutive transmissions are set so as to compensate for the amount of rainfall attenuation due to the rainfall in the area, and the transmission power from the satellite to each of the service areas is set to the set transmission. By being configured to use electric power, it is possible to obtain a continuous transmission control method of a satellite communication system that can set a transmission power amount suitable for rainfall and save the transmission power.

Further, continuous transmission interval setting means for setting a continuous transmission time interval, and continuous transmission interval control for controlling the continuous transmission interval from the satellite to each of the service areas so that the set continuous transmission interval is achieved. By providing the means, it is possible to perform continuous transmission control suitable for the situation, and to obtain a continuous transmission control system for a satellite communication system that can improve reliability.

Furthermore, the continuous transmission interval setting means can perform continuous transmission control suitable for the situation by setting the continuous transmission time interval according to the wind speed of the local weather.
A continuous transmission control system of a satellite communication system that can improve reliability is obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a main part of a satellite communication system according to a first embodiment of the present invention.

FIG. 2 is a graph for explaining the control method according to the first embodiment of the present invention and is a graph showing the number of continuous transmissions with respect to the rainfall amount in one service area.

FIG. 3 is a graph for explaining another control method according to the first embodiment and is a graph showing the number of continuous transmissions and the transmission power with respect to the rainfall amount in one service area.

FIG. 4 is a graph for explaining a control method according to a second embodiment of the present invention and is a graph showing continuous feeding intervals with respect to wind speed in one service area.

FIG. 5 is a configuration diagram showing a main part of a conventional satellite communication system.

[Explanation of symbols]

1 Local Meteorological Information Collection and Distribution Organization 3 Satellite Control Station 4 Satellite 10 Operation / Continuing Transmission Control Devices A, B, C Communication or Broadcast Service Areas Sa, Sb, Sc Regional Meteorological Information Sd of each Service Area A, B, C Meteorological information S10 which is a collection of regional meteorological information of a plurality of service areas. Transmission power / continuous transmission control information.

Claims (5)

[Claims] 1. When communicating or broadcasting to a plurality of service areas via a satellite, the communication to or from each of the service areas is performed on the basis of radio disturbance amount information related to local weather of each of the service areas, which leads to attenuation of communication or broadcast radio waves. A continuous transmission number setting means for setting the continuous transmission number; and a continuous transmission number control means for controlling the continuous transmission number from the satellite to each of the service areas so that the set continuous transmission number is achieved. A feature of the satellite communication system is continuous transmission control. 2. The radio disturbance amount information relating to the local weather is a rainfall amount, and the continuous transmission frequency setting means compensates the rain attenuation amount due to the rainfall amount in the region for each service region. 2. The continuous transmission control method for a satellite communication system according to claim 1, wherein the number of continuous transmissions is set so as to compensate for the amount of rainfall attenuation when it is not possible to secure the above. 3. The radio disturbance amount information relating to the local weather is a rainfall amount, and the continuous transmission frequency setting means compensates the rain attenuation amount due to the rainfall amount in the area for each service area. 2. The satellite communication system according to claim 1, wherein the transmission power and the number of continuous transmissions are set, and the transmission power from the satellite to each of the service areas is set to the set transmission power. Transmission control method. 4. A continuous transmission interval setting means for setting a continuous transmission time interval, and a continuous transmission interval control for controlling the continuous transmission interval from the satellite to each of the service areas so that the set continuous transmission interval is achieved. A continuous transmission control system for a satellite communication system according to any one of claims 1 to 3, further comprising: 5. The continuous transmission control method for a satellite communication system according to claim 4, wherein the continuous transmission interval setting means sets a continuous transmission time interval based on the wind speed of the local weather.