JPH05235802A - Transmission power control system - Google Patents

Abstract

PURPOSE:To prevent interference from being given onto an adjacent line even when a fault takes place in a transmission output control circuit of a transmitter at a sender side. CONSTITUTION:A transmitter 11 at a sender side controls a transmission output in response to reception level information Lr sent from a receiver side. An output detector 14 detects a transmission output level of the transmitter 11. A comparator 15 compares transmission output level information Lt with the reception level information Lr to detect an error in a transmission output and to send an error signal At, which is sent to the receiver side via a multiplexer circuit 16 and the transmitter 11. A receiver 22 at the receiver side detects the error signal At and sends the signal to a changeover controller 24, which selects a line changeover device 61 to the position of a standby line and sends a switching signal Cs to the sender side via a multiplexer circuit 23 and a transmitter 21. A changeover control circuit 13 at the sender side receives the switching signal Cs from the receiver side to throw a line changeover device 51 to the position of the standby line thereby stopping the operation of the transmitter 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission power control system for transmitting a reception level detected by a reception side to a transmission side to control a transmission output level, and particularly to a protection line to a protection line when a failure occurs in a working line. The present invention relates to a transmission power control method applied to a wireless system that performs switching.

[0002]

2. Description of the Related Art In a conventional transmission power control system of this type, as shown in FIG. 2, for example, a transmitter 11 and a receiver 12 for a working line and a transmitter 3 for a protection line are provided on the transmitting side.
1, a receiving device 32, a line switching device 51 and a switching controller 13 respectively. Further, the receiving side is provided with a transmitting device 21 and a receiving device 22 for the working line, a transmitting device 41 and a receiving device 42 for the protection line, a line switching device 61 and a switching control device 24, respectively, and a transmitting device. Device 21
Multiplexing circuits 23 and 43 for transmitting the reception level information to the transmitting side are provided on the input sides of and 41, respectively.

Here, the receiving devices 22 and 42 on the receiving side are
Each has a function of detecting the signal level of the received radio wave and generating reception level information Lr indicating the reception level.
The reception level information Lr is multiplexed on the transmission signal by the multiplexing circuits 23 and 43, and sent to the transmission side via the transmission devices 21 and 41.

Further, the receiving devices 12 and 32 on the transmitting side have a function of detecting the reception level information Lr sent from the receiving side, and further, the transmitting devices 11 and 31 include the receiving devices 12 and 32, respectively. It has a function of controlling the transmission output level according to the detected reception level information Lr. In this case, the transmission output of the transmission side is controlled to increase or decrease according to the increase or decrease of the reception level of the reception side.

By the way, the receiving side switching controller 24 constantly monitors the receiving level information Lr, and switches the line switching unit 61 to the protection line side when the reception level is reduced to a predetermined value or less, and at the same time to the protection line. A switching signal Cs indicating switching is generated and sent to the multiplexing circuit 23. This switching signal Cs is
It is sent to the transmitting side via the transmitting device 21, detected by the receiving device 12 on the transmitting side, and sent to the switching controller 13.

The switching controller 13 switches the line switching device 51 to the protection line side according to the switching signal detected by the receiving device 12. At the same time as switching to the protection line side, the power supply to the transmitter 11 for the working line is cut off.

[0007]

In the above-mentioned conventional transmission power control method, the transmission output of the transmission side is controlled according to the reception level information sent from the reception side. For this reason,
When a failure occurs in the transmission output control circuit of the transmission device on the transmission side and the transmission output abnormally increases, it is impossible to cope with this abnormality, and there is a problem that it interferes with an adjacent line. ..

An object of the present invention is to provide a transmission power control system capable of preventing interference to an adjacent line even if a failure occurs in the transmission output control circuit of a transmitter.

[0009]

The transmission power control method of the present invention is a radio system for switching to a protection line when a failure occurs in a working line, and transmits a reception level detected on the receiving side. In the transmission power control method of transmitting to the side to control the transmission output level, the transmission side detects the transmission output level, the detected transmission output level and the reception level transmitted from the reception side. And means for transmitting an abnormality signal by detecting the abnormality, means for forcibly switching to the protection line when the abnormality signal is received, and means for transmitting the abnormality signal to the receiving side. The receiving side includes means for detecting the abnormal signal transmitted from the transmitting side, and means for forcibly switching to the protection line when the abnormal signal is detected. To have.

[0010]

The present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. The difference from the conventional transmission power control system shown in FIG. 2 is that the transmission output level of the transmitter 11 is detected and the transmission output level is detected. An output detector 14 for sending out information Lt,
To compare the detected transmission output level with the reception level from the receiving side to detect an abnormality and send out the abnormal signal At, and to transmit the abnormal signal At to the receiving side after multiplexing the abnormal signal At with the transmitting signal. That is, the multiplex circuit 16 of FIG. The same blocks are designated by the same reference numerals.

Next, the operation will be described.

Now, when a failure occurs in the transmission output control circuit of the transmission device 11 and the transmission output abnormally increases, the output detector 14 detects the abnormally increased transmission output level of the transmission device 11 and transmits it. The output level information Lt is sent to the comparator 15. On the other hand, the reception side detects the increased reception level, generates reception level information Lr, and transmits it to the transmission side. The comparator 15 compares the transmission output level information Lt with the reception level information Lr from the receiving side. in this case,
Although the reception level information is information for controlling the transmission output to be reduced, the transmission output level is still increased, so that it is determined that the abnormality is present and the abnormality signal At is transmitted. The abnormal signal At is transmitted to the receiving side via the multiplexing circuit 16 and the transmitting device 11.

The receiving device 22 on the receiving side receives the abnormal signal A
t is detected and sent to the switching controller 24. Switching controller 2
When the abnormal signal At is received, or when the reception level information indicates a reception level equal to or lower than a predetermined value, the line switching unit 61 switches to the protection line side and a switching signal Cs indicating switching to the protection line. Is transmitted to the transmitting side via the transmitting device 21.

The receiving device 12 on the transmitting side detects the switching signal Cs and sends it to the switching controller 13. The switching controller 13 is
Upon receiving the switching signal Cs from the receiving side, the line switching device 51 is switched to the protection line side, and at the same time, the power supply to the transmitting device 11 is cut off.

By doing so, even if a failure occurs in the transmission output control circuit of the transmission device, the transmission device is forcibly switched to the standby line and the transmission device is stopped, so that the interference with the adjacent line can be prevented.

In this embodiment, the line switching means when the abnormal transmission output is increased is provided on the working line side, but similar means may be provided on the protection line side.

[0018]

As described above, according to the present invention, the transmitting side detects the transmission output level of the transmitting device, compares the detected transmission output level with the receiving level of the receiving side, and detects an abnormality. And transmit an abnormal signal to the receiving side,
The receiving side detects this abnormal signal and forcibly switches to the protection line, and at the same time, transmits the switching signal to the transmission side. Further, the transmission side detects this switching signal and forcibly switches to the protection line. After switching, by cutting off the power supply to the transmitter for the working line, even if the transmitter output control circuit of the transmitter on the transmitter side fails, the transmitter output will increase abnormally and interfere with the adjacent line. You can avoid it.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing an example of a conventional transmission power control method.

[Explanation of symbols]

 11, 21, 31, 41 transmitter 12, 22, 32, 42 receiver 13, 24 switching controller 14 output detector 15 comparator 16, 23, 43 multiplex circuit 51, 61 line switch Lr reception level information Lt transmission Output level information At abnormal signal Cs switching signal

Claims (1)

[Claims] 1. A radio system for switching to a protection line when a failure occurs in a working line, and transmitting power for controlling a transmission output level by transmitting a reception level detected by a reception side to a transmission side. In the control method, the transmission side, means for detecting the transmission output level,
Means for comparing the detected transmission output level with the reception level transmitted from the receiving side to detect an abnormality and transmitting an abnormality signal; and a means for forcibly forcing the protection line when the abnormality signal is received. And a means for transmitting the abnormal signal to the receiving side, wherein the receiving side detects the abnormal signal transmitted from the transmitting side, and when the abnormal signal is detected And a means for forcibly switching to the protection line.