JPS5939936B2 - Emergency broadcast device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention applies to CATV (Community Antenn
aTelevision) relates to an emergency broadcasting device using railroad tracks.

Conventionally, there are a wide variety of emergency broadcast systems using CATV lines, but all of them are configured by connecting a coaxial line, an amplifier (for example, a trunk amplifier), a coupler to each terminal, etc. in series.

However, this configuration has the disadvantage that if a break in the coaxial line or a failure in the amplifier occurs, broadcasting to further terminals is no longer possible.

This invention was made in view of the above circumstances,
The purpose is to provide a conventional emergency broadcast system using a CATV line with receiving equipment consisting of a linear antenna and an amplifier for radio broadcasting at key points of the system, and to connect this to the CATV line. In addition, by providing a bypass circuit for radio frequency signals between the input and output of the main amplifier of the CATV line, emergency broadcasts to each terminal can also be made by wireless means, thereby creating a highly reliable emergency broadcast system. It is about providing. An embodiment of the present invention will be described below with reference to the drawings.

In the figure, 11 is a transmitting station for transmitting various information to the CATV line and space, 12 and 12' are terminal groups installed at various locations on the CATV line, and 13 and 13' are each installed at important points. Trunk amplifier (trunk amplifier), 14, 14
' is a coupler (directional coupler) for coupling to each terminal,
15 is a transmitting antenna for wireless broadcasting; 16 and 16' are receiving antennas for receiving wireless broadcasting from the transmitting station 11;
IT, ) 17' is an amplifier 1 for amplifying radio frequency signals from the receiving antennas 16, 16' to an appropriate level.
8, 18' is a coupler (bidirectional coupler) for coupling radio frequency signals to both up and down directions of the CATV line;
19 and 19' are bypass filters that allow only radio frequency signals to pass through. Also, 12, 122... and 1
2'0, 12'2, . . . are terminals in the terminal groups 12 and 12', respectively. That is, transmitting station 11
, terminal groups 12, 12', trunk amplifiers 13, 13, and an emergency broadcast system using a conventional CATV line 0, in which radio broadcasting equipment (radio transmitter) is provided in the transmitting station 11, and a transmitting antenna is installed. 15 to enable wireless broadcasting. On the other hand, a receiving antenna for receiving the radio broadcast, which includes receiving antennas 16, 16' and amplifiers IT, IT', is located at key points of the emergency broadcasting device, for example, between the main amplifier 13 and the main amplifier 13'. Equipment is provided and coupled to the CATV line by couplers 18, 18'. In addition, the main amplifiers 13, 13' include a bypass amplifier 1.
9 and 19' are provided so that radio frequency signals can pass even if, for example, the main amplifiers 13 and 13' fail and become disconnected 7. By having the above configuration,
This device has the ability to perform wireless emergency broadcasts in addition to conventional wired emergency broadcasts. Therefore, for example, if the CATV line is cut at point A in the figure, the conventional emergency broadcasting system will
However, since the apparatus according to the present invention is equipped with a radio broadcast means, the radio broadcast from the transmitting antenna 15 is transmitted to the receiving antenna 16.
', and amplified to an appropriate level by amplifier 17'.
By coupling to the CATV line using the coupler 18', emergency broadcasts can be made to the terminal group 12' beyond point A without any problem. Also, for example, the trunk amplifier 13
The same is true in the case of a failure in the bypass transmitter 19', and the radio frequency signal is transmitted to the main amplifier 13' and beyond, regardless of the main amplifier 13', so emergency broadcasting can be carried out without any problem. Can be done.

In the above device, the frequency of wired broadcasting from the transmitting station 11 and the frequency of wireless broadcasting are generally different, but the function to separate the two is provided by each terminal 121, 122, . . .
It is included in 12'1, 12'2...

As described above, according to the present invention, wireless broadcasting means is added to the conventional emergency broadcasting device using the CATV line, and the CATV line. By installing a radio frequency signal bypass circuit between the input and output of the CATV mains amplifier, it eliminates the problem of failure of the mains amplifier, breakage of the CATV line itself, etc., which often occurs in the past, and makes emergency broadcasts extremely reliable. A highly sophisticated emergency broadcasting system can be realized.

[Brief explanation of drawings]

The figure is a block diagram showing one embodiment of the present invention. 11... Transmitting station, 12, 12'... Terminal group, 13, 13'... Trunk amplifier, 14, 1
4'...Coupler, 15...Transmitting antenna, 16,16'...Receiving antenna, 17,1
7'... Amplifier, 18, 18'... Bidirectional coupler, 19, 19'... Bypass filter.

Claims (1)

[Claims] 1. In an emergency broadcasting device using a CATV line, radio broadcasting equipment is provided in the transmitting section of the device, and receiving equipment consisting of a linear antenna and an amplifier for the radio broadcasting is provided at key points of the device. An emergency broadcasting system, characterized in that the emergency broadcasting system is coupled to the CATV line, and a radio frequency signal bypass circuit is provided between the input and output of the main amplifier of the CATV line.