JPS6251398A - Alarm supervision system - Google Patents

Abstract

PURPOSE:To collect data of an alarm generating terminal equipment only at a high speed and in a short time by making an outgoing call from a terminal with the 1st single frequency while placing priority to the alarm of the terminal equipment and applying simultaneous transmission of a universal address signal by the 2nd single frequency from a center to control the stop and restoration of the outgoing of the alarm raising terminal equipment. CONSTITUTION:The system consists of the center 1 and a branch system block 3 where terminal equipments 2 are connected on multi-drop basis and a main transmission line 4 connects the block 3 and the center 1. If an alarm is raised from a terminal equipment 2 in the block 3, the center 1 sends a universal address stop signal to stop forcibly alarming. The center 1 sends sequentially an address signal to all terminal equipments and a reply of alarm raising terminal equipment is returned from an alarm generating terminal equipment only. The reply signal transmission from the alarm generating terminal equipment is stopped automatically and only the said terminal equipment is detected in time series. The processing above is executed consecutively until the address for all the terminal equipments is finished, the alarm generation restoration by a universal address restoration signal is executed to complete one period and the alarm generating terminal equipment makes a call again.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an alarm monitoring system using a branch line network such as a CATV transmission line system for collecting security alarm monitoring information, for example.

[Conventional technology]

Conventionally, this type of alarm monitoring has been carried out in a branch system with a transmission line configuration using multi-drop connections in which all terminals are divided into blocks. I was doing a lot of collecting.

[Miscellaneous invention/problem to be solved] In the conventional alarm monitoring system described above, polling is started sequentially from the terminal at the beginning of the first block, and when polling of the terminal at the end of the first block is completed. Move to the next second block. The first terminal address of the second block is next to the last terminal address of the first block, and the process moves on to the third block in the same manner. For this reason, if the terminal generating the alarm is in the n-th block towards the end, the number of polling steps up to that point increases, the time required becomes longer, and there is a drawback that data cannot be collected urgently.

[Means for solving problems]

In order to solve such problems, the present invention transmits a terminal transmission using a first single frequency from an alarm generating terminal to a center, and in response, the center transmits a terminal transmission using a second frequency common to all terminals. After transmitting a unipurple address stop signal using one frequency to stop the corresponding terminal from transmitting, the address signals of all terminals in the block are continuously transmitted from the first address, and the time and center when the alarm generating terminal retransmits are transmitted. This system detects all the alarm-generating terminal addresses based on the timing of the address signal continuous sending time, and repeats the operation of sending out a recovery signal equivalent to stopping the UniPurple address again, thereby periodically and continuously monitoring the alarm-generating terminals. be.

[Effect]

The alarm generating terminal will send the alarm again if the address is specified. If there are a plurality of alarm generating terminals, re-transmission will occur sequentially as addressing progresses, and all alarm generating terminals will be extracted. As the periodic monitoring operation is repeated, terminals that have recovered will no longer make calls again.

〔Example〕

FIG. 1 is a time chart of a two-frequency monitoring system showing one embodiment of the present invention. When the first single frequency signal F1 is transmitted from the alarm generating terminal as shown in (,) in Fig. 1 (4), the center that receives it transmits the first single frequency signal F1 as shown in Fig. 1(4) (,). A second single frequency signal F2 different from the single frequency is transmitted. This signal is a universal address stop signal with a fixed time common to all terminals in the same block 69 and simultaneously cuts off all the first single frequency signals of the alarm generating terminals.

After this timing, address signals A are sequentially sent from the center to all terminals, as shown in FIG. 2(C). When the first alarm generating terminal (address ap) is specified, that terminal is assigned the first alarm for a predetermined fixed period of time as shown in FIG.
retransmit the single frequency signal F1. Depending on the coincidence of the detection time and the continuous transmission time of the address signal A, the center can know the terminal that generated the first alarm. Next, the center immediately resumes continuous transmission of the address signal A from the next address as shown in FIG. ), the second alarm generating terminal (address IL9) is detected. In this way, the center responds to the address signal A by the first single frequency signal F1 sent only from the alarm generating terminal.
The detection is performed one after another until the sending of the address ends at the last address (aX) as shown in (a) of FIG. 1(B). Meanwhile, as shown in FIG.
If there is no response signal of 1, it indicates that the terminals at those addresses are not alarm generating terminals. One! ! The address signal A becomes a signal that is discarded without making any response in terminals other than the alarm generating terminal.

Next, the center sends out a universal address recovery signal consisting of a second single frequency signal F2, which is equivalent to the universal address stop signal, as shown in (,) in C) of Figure 1, and again causes the alarm generation terminal to transmit the first signal. After transmitting the single frequency signal F1 as shown in the same figure (C),
As shown in FIG. 2, a universal address stop signal consisting of a second single frequency signal F2 is transmitted all at once. Thereafter, address signals A similar to those described above are sequentially sent out, and the alarm generating terminal is detected in the same procedure.

FIG. 2 is a block diagram of a system to which the embodiment can be applied. The system consists of a center 1 and a branch block 3 that has multi-drop connections to terminals 2.
A main transmission line 4 connects the block 3 and the center 1.

On the other hand, FIG. 3 is a flowchart showing the flow of operations corresponding to the time chart in FIG. The arrows in FIG. 2 indicate the direction of signal flow at each step in FIG.

In the above configuration, when an alarm is generated from the terminal 2 in the block 3 (step 101), the center 1 forcibly stops issuing the alarm by means of a universal address stop signal (step 102). Subsequently, the address signals of all terminals are sequentially transmitted from the center 1 (step 103), and in response, a response from the alarm generating terminal is returned only for the alarm generating terminal (step 104). The transmission of response signals from the alarm generating terminal is automatically stopped, and only the alarm generating terminal is detected in chronological order (step 105).

The above steps 103 to 105 are continued until all terminal addresses are completed (step 106), and then alarm generation recovery is performed by the universal address recovery signal (step 107), and one cycle is completed, and the alarm is issued again. The originating terminal makes the call. As a result, the alarm generation step 1
Returning to 01, the process similarly moves to step 102 forcibly stopping alarm transmission, but if the alarm on the original terminal side recovers naturally in one cycle period up to alarm generation recovery step 107, terminal 7 will not be able to transmit again. Step 1: Stop the alarm transmission from the center 1 using the universal address stop signal.
02 is basically not performed. Note that if no alarm occurs, it is also possible to perform one cycle in the same manner as above for normal testing.

〔Effect of the invention〕

As explained above, according to the present invention, the terminal transmits the terminal signal using the first single frequency, giving priority to the alarm on the terminal side, and the center transmits the uniperful address signal simultaneously using the second single frequency. The system controls the stopping and restoring of the alarm generation terminal's transmission, repeats this period continuously, and the center extracts only the response of the alarm generation terminal within that period. This has the effect of allowing data collection to be performed quickly and in a short period of time.

Also, based on two-frequency monitoring, in which a first single frequency is used for terminal transmission and a second different single frequency is used for center transmission9, the continuous transmission of address signals from the center is, for example, This can be achieved by a first single frequency FSK frequency shift. In other words, by realizing uplink and downlink carrier waves using two frequencies, the total number of terminals is 2.
It has the advantage of being able to increase efficiency in terms of frequency, and in terms of occupation by band division, it is efficient in a narrow band because it uses two waves.

[Brief explanation of the drawing]

FIG. 1 is a time chart showing one embodiment of the present invention, and FIG.
The figure is a system configuration diagram, and FIG. 3 is a flowchart corresponding to the time chart of FIG. 1. Fl...first single frequency signal, F2...
. . . second single frequency signal, A . . . address signal,
S...Address of the bow-th alarm generating terminal, a,...
・Address of the second alarm generating terminal, &...Last address, 1...Center, 2...Terminal, 3...
...Block, 4... Main transmission line. Patent Applicant: NEC Corporation Agent Masaki Yamakawa (#12) Figure 1 (B) Δ

Claims (1)

[Claims] In an alarm monitoring system in which all terminals are divided into blocks, an alarm generating terminal transmits a first single frequency signal, and the center that receives the single frequency transmits a second single frequency signal different from the first single frequency. A universal address stop signal with a fixed time common to all terminals in the same block based on the frequency is sent out all at once to stop the corresponding terminals in the alarm block from transmitting, and then all terminal address signals are continuously sent from the first address. By causing the alarm generating terminals that have been addressed to re-transmit for a fixed time, all alarm generating terminals are extracted from that time and the timing of the address signal continuous sending time of the center, and a third address signal equivalent to the universal address stop signal is added within the block. The second single-frequency universal address recovery signal is sent out, and the first single-frequency signal is sent again from the alarm generating terminal, and the period from sending out the universal address stop signal to sending out the universal address recovery signal is regarded as one cycle, and the original alarm is activated. An alarm monitoring method characterized in that the alarm monitoring method is repeatedly executed until the occurrence naturally recovers and the terminal stops transmitting.