JPH05183477A - Transmitter-receiver at earth station for satellite communication - Google Patents

Abstract

PURPOSE:To save the power consumption and to reduce the burden of a battery incorporating a land mobile station by permitting a control means to stop the power supply based on the battery to the load when an unreceivable stopping state is detected. CONSTITUTION:In the transmitter-receiver of the earth station for satellite communication, a reception state detection signal (a) indicating whether or not the reception from a reception circuit 8 can be performed is inputted from a detection means 6 through an interface 11a to a control means 12. The can speed signal V is inputted via an interface 11c to the control means 12 from the can speed sensor 13. The control means 12 judges whether or not the unreceivable land mobile station is in the unreceivable stopping state of the stopping state based on the inputted reception state detection signal (a) and the car-speed signal (v). As a result, when it is judged to be an unreceivable stopping state, the control means 12 inputs the on-state power saving control signal (b) through an interface 11b to a load switch 9, making the closed state. Thus, the voltage V is not supplied to a transmission/reception circuit 7 and the power consumption can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitter / receiver for an earth station for satellite communication, which is mounted on a land mobile body and is supplied with power from a battery.

[0002]

2. Description of the Related Art One of the geostationary satellite communication systems is the Inmarsat standard C system (hereinafter referred to as the C system). This C system was started as a system for data communication between sea vessels and ground. Has been introduced in land mobile communications as well as maritime vessels.

When the transmitter / receiver of the earth station for satellite communication in the C system is mounted on a land mobile body and used, the transmitter / receiver is generally driven by a battery mounted on the land mobile body.

When communication is performed by the above-mentioned transmitting / receiving device, if there is an obstacle such as a building between the Inmarsat geostationary satellite and the land mobile, communication becomes impossible. Building, bridge,
When traveling in the city center with many obstacles such as tunnels, it is often impossible to receive signals and stop at a signal. In such a case, since communication is impossible, transmission / reception is not performed.

[0005]

As described above, in the state of being incapable of receiving and in the state of being stopped due to waiting for a signal or the like, communication is impossible even if transmitting and receiving, so that neither transmission nor reception is performed. In the case of the transmitter / receiver of the earth station for satellite communication, the power supply was supplied from the on-board battery even if neither transmission nor reception was performed, and power was wasted.

The present invention has been made in consideration of the above circumstances. An object of the present invention is to reduce the power supply by stopping the supply of unnecessary power supply, thereby reducing the burden on the battery mounted on the land mobile body. Is to reduce.

[0007]

In order to solve the above-mentioned problems, according to the present invention, a receiver / transmitter of a satellite communication earth station mounted on a land mobile body and supplied with power from a battery cannot receive data. A reception state detection means for detecting whether or not the reception state detection signal is output, a vehicle speed detection means for outputting a vehicle speed signal for determining whether the land vehicle is in a running state or a stopped state, and the reception state detection signal And a vehicle speed signal, and control means for determining whether or not it is unreceivable and the land mobile body is in the unreceivable stop state of the stop state, and the control means determines that it is in the unreceivable stop state. When this is done, the power supply from the battery to the predetermined load is stopped.

[0008]

In the transmitting / receiving apparatus of the earth station for satellite communication according to the present invention, as shown in FIG. 1, the reception state detection signal a indicating whether the reception is impossible or not is transmitted from the reception state detection means 6 through the interface 11a to the control means. Entered in 12, and again
A vehicle speed signal v indicating the vehicle speed is input from the vehicle speed detection means 13 to the control means 12 via the interface 11c.

The control means 12 determines from the received reception state detection signal a and the vehicle speed signal v whether or not the reception is impossible and the land mobile body is in the reception impossible stop state of the stop state,
When it is determined that the reception cannot be stopped, the power supply from the battery to the predetermined load 7 is stopped.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a transmitting / receiving apparatus for an earth station for satellite communication according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a transmitting / receiving apparatus for an earth station for satellite communication according to the present invention. This apparatus is mounted on a land mobile body and is supplied with power from a battery.

At the time of transmission, the transmission data signal TD is transmitted by the transmission circuit 3
In addition, since the terminal 2b and the common terminal 2a of the transmission / reception changeover switch 2 are connected during transmission, the output of the transmission circuit 3 is input as a transmission signal to the antenna 1 via the transmission / reception changeover switch 2 (hereinafter , Terminal 2b and common terminal 2a
The state in which and are connected is called the "sending side connection state").

At the time of reception, the transmission / reception changeover switch 2 has a terminal 2c.
And the common terminal 2a are connected to each other, the output of the antenna 1 is transmitted through the transmission / reception changeover switch 2 to
It is input to the intermediate frequency circuit (RF / IF circuit) 4 as a high-frequency reception signal (hereinafter, a state in which the terminal 2c and the common terminal 2a are connected is referred to as a "reception side connection state").

The high frequency received signal is converted into an intermediate frequency received signal by the high frequency / intermediate frequency circuit 4 and output.
The intermediate frequency reception signal is demodulated by the demodulation circuit 5 and output as a reception data signal RD. The demodulation circuit 5 also outputs a discrimination signal for discriminating the state of the reproduced carrier. This discrimination signal is input to the carrier lock detection circuit (reception state detection means) 6 and is output as a carrier lock detection signal (reception state detection signal) a indicating whether reception is impossible. The carrier lock detection signal a is input to the CPU (control means) 12 via the interface 11a.

On the other hand, a vehicle speed sensor (vehicle speed detecting means) 13 attached to a land moving body such as an automobile outputs a vehicle speed signal v indicating the vehicle speed. This vehicle speed signal v is a signal for determining whether the land vehicle is in a stopped state or a running state,
It is input to the CPU 12 via the interface 11c.

From the inputted carrier lock detection signal a and vehicle speed signal v, the CPU 12 determines whether or not it is in the unreceivable state and the land mobile body is stopped (hereinafter referred to as the unreceivable stop state). .. When it is determined that the reception cannot be stopped, the CPU 12 turns on the power saving control signal b.
Is input to the load switch 9 via the interface 11b to bring the load switch 9 into the "open" state. As a result, the power supply of the voltage V is not supplied to the transmission / reception circuit 7 as a load, and the power consumption in the transmission / reception circuit 7 is eliminated.

Further, the power saving control signal b in the on state is input to the power saving mode terminal 12a of the CPU 12 itself via the interface 11b. As a result, the CPU 12
Becomes a power saving mode, and power consumption in the CPU 12 is also reduced. Although the CPU 12 slows down the calculation speed in the power saving mode, when the vehicle speed signal v recognizes that the land vehicle is in the traveling state again, the power saving control signal b is turned off and the load switch 9 is closed. At the same time, the CPU 12 itself is released from the power saving mode and returns to the normal calculation speed.

The reference signal generating circuit 10 shown in FIG. 1 has a transmitting / receiving circuit 7, CP for determining a transmitting / receiving frequency and a clock frequency.
The reference signal r is input to U12. Reference signal generation circuit 10
Has an oscillator as its constituent element, but since the oscillation frequency of the oscillator is not stable when the power is turned on, it is always energized and excluded from the target of power saving.

As described above, in this embodiment, the power supply to the transmission / reception circuit 7 is stopped in the non-reception stop state, and the CPU 12 is set in the power saving mode to reduce the power consumption. Each time the vehicle is stopped, power is saved and the burden on the battery mounted on the land mobile is reduced. This effect is particularly great in areas with many buildings, bridges, and tunnels.

In the above embodiment, the power is saved in the unreceivable state, but the power can be similarly saved in the untransmittable state. For example, if a line request for transmission is issued but no line allocation is returned, it is considered that transmission is impossible, and the CPU 12 can perform the same processing as when reception is impossible.

[0021]

As described above, since the transmitting / receiving device of the earth station for satellite communication according to the present invention stops the supply of the power source by the battery to the predetermined load in the unreceivable stop state, the battery The power consumption can be reduced and the load on the battery can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a transmitting / receiving apparatus of an earth station for satellite communication according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 antenna 2 transmission / reception change-over switch 3 transmission circuit 4 high frequency / intermediate frequency circuit 5 demodulation circuit 6 carrier lock detection circuit (reception state detection means) 7 transmission / reception circuit 8 reception circuit 9 load switch 10 reference signal generation circuit 11a to 11c interface 12 CPU ( Control means) 13 Vehicle speed sensor (vehicle speed detection means)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masami Abe 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (1)

[Claims] 1. A receiving state detecting means for detecting whether or not reception is impossible and outputting a receiving state detection signal in a transmitting / receiving device of a satellite communication earth station mounted on a land mobile body and supplied with power from a battery. And a vehicle speed detecting means for outputting a vehicle speed signal for determining whether the land vehicle is in a running state or a stopped state, and the reception detection signal and the vehicle speed signal are inputted, and reception is impossible and the land vehicle is in a stopped state. And a control means for determining whether or not it is in the unreceivable stop state, and the control means stops the power supply to the predetermined load by the battery when it is determined that the unreceivable stop state. The transmitting / receiving device of the earth station for satellite communication.