JP2998705B2 - Line connection control method - Google Patents

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, and more particularly, to a line connection technique for effectively using the transmission power of an earth station to its limit.

[0002]

2. Description of the Related Art FIG. 4 is a schematic diagram showing this type of conventional technology.

Referring to FIG. 4, this type of system is:
A satellite 5 and a plurality of earth stations, that is, a master station earth station device 7
, A satellite line allocating device 8 connected to the master station 7, a slave station earth station device 7 ', and a satellite line allocating device 8' connected to the slave station 7 '. In a mesh-type satellite communication system to which lines can be arbitrarily assigned, for example, DAMA (DEMAND ASSIGNME)
A line allocation method known as NT MULTIPLEACCESS has been widely used as a technique that can effectively use a limited satellite line.

[0004] In addition, a line control technique for restricting transmission of a carrier exceeding the limit due to the restriction of the transmission power of each earth station has been conventionally used.

[0005] However, not only DAMA but also a conventional line assignment method, a call from each slave station is uniquely assigned a line route by a dial number.

[0006]

However, the prior art has the following problems.

[0007] A problem with the conventional line assignment method is that a call from each slave station is uniquely connected to the line via the shortest route determined by the dial number or a predetermined route. However, when the call is destined for the slave station even when the transmission power is insufficient but the master station has a sufficient margin, the line connection is not performed because the transmission power is insufficient. For this reason, the traffic between the slave stations is limited.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and has been made to solve the above-mentioned problems inherent in the conventional technology. Therefore, the object of the present invention is to pass through a master station in the above situation. It is an object of the present invention to provide a new line connection control system which can connect a call which has been lost by the route assignment and increase the line connection ratio of the entire satellite line.

Normally, double hopping through a satellite twice is not preferable in a satellite line. However, it is an object of the present invention to remedy a case in which a line is not connected in spite of a margin in earth station transmission power. Is the purpose.

[0010]

In order to achieve the above-mentioned object, a line connection control system according to the present invention comprises a satellite line allocating device (2, 2 'in FIG. 1) installed in a master station and a slave station. A call discrimination device (3 in FIG. 1) for discriminating whether a call from a terminal such as a telephone is directed to a master station or a slave station, and a transmission power monitoring device (4 in FIG. 1) installed in the slave station. It is comprised including.

The transmission power monitoring device is a power monitor for measuring the total power to be transmitted or a power measurement / calculation device for calculating the total power currently being transmitted from the number of transmission carriers and the power determined by the transmission destination of each carrier; And a power margin calculation device for calculating how much the transmission power measured by the power measurement / calculation device or the calculated transmission power has a margin compared to the maximum possible transmission power of the earth station.

Information such as the power and the margin of the power is transmitted to the master station as a monitoring signal of the slave station.

A call discriminating device for discriminating whether a call from a terminal such as a telephone is destined for a master station or a slave station can be built in the slave station.

[0014]

In the present invention, the transmission power monitoring device installed in the slave station measures the power transmitted by the slave station by the power monitor. Alternatively, the power currently being transmitted is calculated from the number of transmission carriers and the power determined by the destination of each carrier. The measured or calculated transmission power is then compared to the maximum possible transmission power of the earth station to calculate how much margin there is. This information is transmitted to the master station as a monitoring signal of the slave station.

The satellite line allocating apparatus allocates a communication line between the slave stations in response to a request signal from the slave station. It is determined whether the inter-communication is made through a direct line or via a master station. Based on the result, the master station line allocating device sets a line to be allocated to the slave station line allocating device. The slave station line allocating device sets a line of the slave station earth station device (1 'in FIG. 1) in response to a command signal from the master station line allocating device.

As an example, the effect will be verified with reference to the following line design values.

Satellite: INTELSAT-7 Master station G / T: 34.2 (DB / K) Slave station G / T: 17.9 (DB / K) Transmission signal speed: 17.5 (KBPS) Transmission power: 33.6 (DBW) Transmission power to slave station: 46.7 (DBW) Maximum possible transmission power of slave station: 47.3 (DBW) In this example, a direct line from the slave station to the slave station is used. Can transmit only one carrier, but 0.6DB (= 47.3)
−46.7), so that three carriers can be transmitted to the master station at the same time. Therefore, when a call to a slave station has two or more carriers, by setting a line passing through the master station, it is possible to simultaneously set a line to four carriers.

In the above example, the above-mentioned result is obtained because there is a difference in power required for the master station and the slave station of 13.1DB (= 20.4 times).

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

[Description of Configuration] Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention.

Referring to FIG. 1, according to the present invention, a transmission power monitoring device for monitoring or calculating the transmission power on the slave station side, and a line allocating device and each call are managed based on information from the transmission power monitoring device. It is composed of a combination with a call discriminating device that judges whether it is for a station or a slave station. In other words, the earth station transmitting / receiving device for master station (hereinafter abbreviated as master station device) 1 includes a line allocating device for master station 2 and a call discriminator for master station / child station (hereinafter abbreviated as call discriminator). 3 are connected.
Earth station transmitter / receiver for slave station (hereinafter abbreviated as slave station apparatus)
1 'is connected to a slave station line allocation device 2' and a transmission power monitoring device 4.

Here, as shown in the second embodiment shown in FIG. 2, a call discriminating device 3 for judging whether each call is directed to a master station or a slave station is provided on the slave station side. It is also possible to adopt a configuration in which it is performed. In this case, such information is also transmitted to the master station.

In FIG. 1, a master station device 1 and a slave station device 1 'are shown.
The earth station transmitting / receiving section is composed of a power amplifier, a low noise receiver, a modem and the like. The master station and slave station line allocation devices 2 and 2 'have a function of allocating which channel to use when a call request is received from a terminal device such as a telephone.

The call discriminating apparatus 3 is a kind of exchange, and has a function of judging, for example, from a dial number whether a destination to be connected belongs to a master station apparatus or a slave station apparatus. This function can be built in each slave station device, or can be incorporated as a function in the line allocation devices 2, 2 '.

The transmission power monitoring device 4 has a power meter function as an example, and measures the power to be transmitted. Alternatively, it is a device programmed so that transmission power can be calculated by counting the number of transmission carriers using a preset parameter.

[Explanation of Operation] As shown in FIG. 1, in the present invention, a transmission power monitoring device 4 for monitoring or calculating the transmission power on the slave station side and a line allocation device 2, 2 based on information from them. The line assignment is dynamically performed by a combination of 'and a call discriminating device 3 for judging whether each call is directed to a master station device or a slave station device.

This situation will be described with reference to the above example. Normally, the lines between slave station devices are allocated so as to be directly connected without passing through the master station device, but in the above example, the transmission power of the slave station device can directly connect the line to another slave station. The one
Carrier is the limit. In a situation where the slave station-1 and the slave station-2 are transmitting and communicating one carrier at a time, the slave station-1 to the slave station-
When there is a new line connection request to the slave station 2, the slave station-1
Transmits from the transmission power monitoring device 4 to the master station device 1 that the transmittable power of the slave station-1 has only a margin of 0.6DB together with the call information.

Based on this information, the master station device 1 sets a line via the master station device 1 by the line allocating devices 2 and 2 'for a new line connection request. In the situation where the line of one carrier has already been set up and communication is being performed with another slave station device, and a request for a call to the slave station device is further made,
These calls, which have been truncated in the past, can be allocated by assigning a line via the master station 1 according to the present invention.
In the above example, up to three carriers can be connected.

That is, a maximum of four carriers can be connected, including one carrier of a direct connection line between slave stations.

FIG. 2 is a block diagram showing a second embodiment according to the present invention.

Referring to FIG. 2, the difference from the first embodiment is that the call discriminating device 3 and the transmission power monitoring device 4 are switched between the master station and the slave station.
That is, the transmission power monitoring device 4 is connected to the satellite line assignment device 2 of the master station device 1, and the call discrimination device 3 is connected to the satellite line connection device 2 'of the slave station device 1'.

FIG. 3 is a block diagram showing a third embodiment according to the present invention.

Referring to FIG. 3, the third embodiment differs from the first embodiment in that the transmission power monitoring device provided on the slave station side is different from the master station. It is arranged on the device side. That is, the transmission power monitoring device 4 is removed from the slave station device 1 ′, and is connected to the satellite channel assignment device 2 of the master station device 1.

[0034]

Next, the present invention will be described in detail with reference to a preferred embodiment.

FIG. 1 shows an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an earth station transmitting / receiving apparatus (for a master station), 1 'denotes a slave station apparatus thereof, 2 denotes a line allocating apparatus (for a master station), 2 'is a slave station device, 3 is a call discrimination device that determines whether each call is directed to a master station or a slave station, and 4 is a transmission power monitoring device provided in the slave station.

The internal line allocating device 2 monitors the entire satellite communication line network and allocates lines, and instructs each station which line to use when a call is requested. When the call from the slave station is directed to the slave station together with the line allocating device 2, the call discriminator 3 which determines whether the call from each slave station is directed to the master station or the slave station is transmitted by the calling slave station. If the available power has a margin, a line for directly connecting slave stations is allocated, and if there is no margin, a line passing through the master station is allocated. The transmission power monitoring device 4 is a device that monitors the transmission power of the slave station and transmits to the master station whether there is enough available transmission power.

Here, the call discriminating device 3 can be provided in each slave station. Since the required transmission power of the earth station for each call is determined by the performance of each earth station to be received, the power transmitted from each earth station should be calculated by measuring the destination of each call and the number of transmission carriers. Therefore, the transmission power monitoring device 4 can be configured in the master station by providing the master station with this function. This example is shown in FIG. 2 and FIG.

[0038]

As described above, according to the present invention,
In a satellite communication system including a large-sized master station and a plurality of slave stations, an effect of enabling communication between slave stations when the transmittable power of the slave station has no margin for direct communication between slave stations is obtained.

The reason is that the required transmission power for the master station can be several times to several tens times lower than the required transmission power for the normal slave station. It is possible to rescue calls that have been truncated.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a first embodiment of the present invention.

FIG. 2 is a schematic block diagram showing a second embodiment according to the present invention.

FIG. 3 is a schematic block diagram showing a third embodiment according to the present invention.

FIG. 4 is a schematic block diagram showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Earth station transmitting / receiving apparatus for master station 1 '... Earth station transmitting / receiving apparatus for slave station 2 ... Line allocating apparatus for master station 2' ... Line allocating apparatus for slave station 3: Call discriminating apparatus for master station / slave station 4. Transmission power monitoring device 5: Satellite 7: Prior art master station device 7 ': Prior art slave station device 8: Prior art master station line assignment device 8': Prior art slave station line assignment device

Claims (5)

(57) [Claims] 1. A satellite communication system comprising a large master station and a plurality of small slave stations, wherein the master station and each slave station are provided with a satellite channel allocating device, and each slave station has a transmission carrier number or transmission number. A transmission power monitoring device that monitors power,
The master station has a call discrimination device for identifying whether a call from a terminal such as a telephone is directed to the master station or a slave station, and the call is directed to the slave station at each slave station and the transmission power is reduced. A line connection control characterized by allocating a line so as to transmit the carrier for the slave station via the master station when the carrier for the slave station cannot be transmitted any more than the limit, but there is room for the master station. method. 2. The line connection control system according to claim 1, wherein said transmission power monitoring device provided in each of said slave stations is provided in said master station instead of said respective slave stations. . 3. The transmission power monitoring device provided in each of the slave stations is provided in the master station instead of the respective slave stations, and the call discriminating device provided in the master station is provided in the master station. 2. The line connection control system according to claim 1, further comprising a sub-station provided instead of a sub-station. 4. The transmission power monitoring device according to claim 1, wherein the transmission power monitoring device measures a total power to be transmitted or a power measurement / calculation that calculates a total power currently being transmitted from the number of transmission carriers and power determined by a transmission destination of each carrier. Means, and power margin calculating means for calculating the transmission power measured by the power measuring / calculating means or how much the calculated transmission power has compared to the maximum possible transmission power of the earth station. 2. The line connection control method according to claim 1, further comprising transmitting information such as the power and the power margin to the master station as a monitoring signal of the slave station. 5. The satellite link allocating device of the master station receives a request signal from the slave station and allocates a communication line between the slave stations. Based on the above information, a determination is made as to whether the communication between slave stations is a direct line or via a master station, and based on the determination result, a line to be assigned to the satellite line assignment device of the slave station is set. 5. The line connection control method according to claim 4, wherein the satellite link assignment device of the slave station sets a line of the slave station in response to a command signal from the satellite link assignment device of the master station.