JPH0669840A - Rebroadcasting device - Google Patents

Abstract

PURPOSE:To reduce transmission lines between a receiver and a retransmitter by sending the batch multi-tuning signal of radio waves broadcasted from respective stations to a branch filter part, converting the frequency, amplifying the power, mixing those signals and broadcasting a weak radio wave area from an antenna. CONSTITUTION:A rebroadcasting device 30 receives the FM or AM broadcasting radio waves of plural channels from an antenna 14. Those broadcasting signals are inputted through a filter 32 and a high frequency amplifier part 33 to a multituning part 34 and multi-tuned with broadcasting signals f1, f2.... These broadcasting signals f1, f2... are converted to broadcasting signals F1a, F2a... of an intermediate frequency component by a frequency conversion part 35 and turned to broadcasting signals F1b, F2b... enlarged by an elarging part 37. These broadcasting signals are sent through a single transmission line 38 to retransmitters 19a, 19b..., the frequency of the respective broadcasting signals is converted, and power is amplified. These broadcasting signal returned to the original broadcasting signals are sent to a mixing part 20 and sent to a transmission antenna 13 as mixed signals, and the weak areas are broadcasted. Thus, the transmission lines connecting the reception part and the retransmission part are reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rebroadcasting device, and more particularly to a rebroadcasting device adapted to send broadcast radio waves of a plurality of channels in a weak radio wave area.

[0002]

2. Description of the Related Art Generally, a rebroadcast device is installed in a tunnel, a shadow of a building, or the like because a broadcast radio wave from a broadcast station does not reach directly or is weak. As shown in FIG. 4, the rebroadcasting device 10 includes a receiving unit 11, a retransmitting unit 12, a transmitting antenna 13, and the like.

The receiving section 11 is provided with a common receiving antenna 14 for receiving each broadcast radio wave installed in a region or place where a plurality of broadcast radio waves transmitted from a plurality of broadcast stations can be received. The receiving antenna 14 is connected to a distributor 15 composed of a plurality of filters so that a plurality of received broadcast signals can be distributed and passed. A plurality of receivers 16a, 16b, ... Are connected to the distribution unit 15, and one broadcast signal is selected in synchronization with each set broadcast signal to perform frequency conversion or the like. Each of these receivers 16a, 16b ...
Transmission lines 17a, 17b such as cables from 100 m to several hundred m
Are connected to send a frequency-converted broadcast signal to the retransmitting section 12 installed in a weak radio wave area, for example, near the tunnel 18.

The transmission lines 17a, 17b, ... Are connected to the retransmitters 19a, 19b, .. of the transmission section 12 for converting the received broadcast signal into a broadcast signal of the original frequency by frequency conversion and amplification, and We are trying to increase the output. A mixing unit 20 is connected to the retransmitters 19a, 19b, ..., and mixes broadcast signals to supply to a transmitting antenna 13 installed in a tunnel 18.

Reference numeral 21 is a terminating resistor for impedance matching provided at the end of the transmitting antenna 13.

FIG. 5 shows the internal structure of the receiver 16a. The distribution unit 15 of the receiving unit 11 includes a tuning unit 22.
Are connected, and one of the plurality of broadcast signals sent from each broadcast station is selected. This tuning unit 22
A high frequency amplifier 23 is connected to the high frequency amplifier 23, and high frequency amplification of the broadcast signal is performed. A tuning unit 24 is further connected to the high frequency amplifying unit 23, and tuning with a broadcast signal is performed again.

A frequency conversion section 25 is connected to the tuning section 24. A local oscillator 26 is connected to the frequency converter 25. Therefore, the frequency conversion unit 2
In 5, the intermediate frequency component of the difference between the frequency of the broadcast signal and the frequency of the local oscillation signal supplied from the local oscillation unit 26 is extracted, and the broadcast signal converted into this intermediate frequency component is reproduced via the transmission line 17a. It is adapted to be transmitted to the transmitter 19a.

Although the receiver 16a has been described above, the other receivers 16b, etc. are also configured in substantially the same manner as the receiver 16a, and a description thereof will be omitted.

In such a rebroadcasting apparatus 10, when the receiving antenna 14 receives a plurality of channels of FM or AM broadcast radio waves sent from a plurality of broadcasting stations, the broadcast signal is sent to the distributor 15. The distribution unit 15 distributes the broadcast signal so as to correspond to each broadcasting station, and the distributed signal is sent to the receivers 16a, 16b, .... These receivers 16a, 16b ... tune, amplify, tune the distributed signal,
After frequency conversion and the like, the broadcast signals of the respective intermediate frequency components are sent to the respective retransmitters 19a, 19b ... Through the respective transmission lines 17a, 17b.

The retransmitters 19a, 19b ... Amplify the broadcast signal of the intermediate frequency component, frequency-convert it to the original broadcast signal, and send it to the mixing section 20. A mixed broadcast signal is sent from the mixing section 20 to the broadcast antenna 13 to broadcast in a weak area in the tunnel.

[0011]

By the way, in the conventional rebroadcasting apparatus having the above-mentioned configuration, the broadcast signal is distributed to each channel allocated to each broadcasting station, and the distributed signal is distributed to each receiver. It was designed to be sent to each re-transmitter and then restored to the original broadcast signal before broadcasting. Therefore, there is a problem that as the number of broadcasting stations increases, the number of receivers and retransmitters must be increased in accordance with the increase in the number of installations, which increases the installation work.

Further, there has been a problem that as the number of broadcasting stations increases, the number of receivers and re-transmitters is increased and the number of dedicated transmission lines connecting the receivers and re-transmitters increases.

Moreover, the shortest transmission line is several tens of meters.
However, depending on the installation location of the receiver, it can reach up to several hundred meters. Therefore, not only the facility cost is required,
There is a problem that the transmission loss of the broadcast signal increases.

Therefore, the present invention has been made in consideration of the above circumstances, and an object thereof is to provide a rebroadcasting device in which the number of transmission lines connecting a receiver and a retransmitter is reduced. It is a thing.

[0015]

In order to achieve the above object, the present invention is directed to a receiver for receiving broadcast radio waves of a plurality of channels, a re-receiver for power-amplifying a broadcast signal received by the receiver, and a receiver for the receiver. In a rebroadcasting device including a transmission antenna that radiates broadcast radio waves in a weak radio wave area that receives a transmission signal transmitted by a reception unit, the reception unit includes a multi-tuning unit that performs multi-tuning with broadcast signals of a plurality of channels, A frequency conversion unit that is connected to the multi-tuning unit and converts a frequency is provided, the frequency conversion unit is connected to a single transmission unit that transmits a frequency conversion signal, and the re-reception unit includes the transmission unit. A demultiplexer that demultiplexes the frequency-converted signal to be transmitted, a plurality of retransmitters that perform power amplification on the demultiplexed signals that the demultiplexer demultiplexes, and restore the original broadcast signal, and each of these retransmitters. The output signals of the above are mixed and transmitted. There is provided a rebroadcast apparatus characterized in that a mixing unit for sending the antenna.

[0016] Further, the present invention provides a rebroadcasting device characterized in that the frequency conversion section is provided with an expansion section for expanding the frequency conversion signal.

[0017]

Function: Broadcast radio waves transmitted from each broadcasting station are received, and these broadcast signals are collectively tuned. This multi-tuned signal is sent to the demultiplexing section via a single transmission line. Frequency conversion of this demultiplexed signal, power amplification, etc. are performed, mixed, and sent to the transmitting antenna to broadcast in the weak radio wave region.

The intermediate frequency component broadcast signal is expanded and then demultiplexed.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the rebroadcasting device of the present invention will be described below with reference to FIG.

FIG. 1 is a block diagram showing an embodiment of the rebroadcasting apparatus 30 of the present invention. This rebroadcast device 30 is shown in FIG.
Since it is basically the same as the conventional rebroadcasting device 10 shown in FIG. 2, the same parts are denoted by the same reference numerals and detailed description will be omitted.

The receiving section 31 of the rebroadcasting device 30 is provided with a receiving antenna 14 for receiving a plurality of broadcast radio waves transmitted from a plurality of transmitting stations (not shown). A filter 32 having a predetermined bandwidth is connected to the receiving antenna 14,
The broadcast signal from the transmitting station is taken out. This filter 3
A high frequency amplifier 33 is connected to 2 and high frequency amplification of the broadcast signal is performed. The high-frequency amplification unit 33 includes a multi-tuning unit 3
4 are connected, and a high Q corresponding to a plurality of channels F1, F2, F3, ... Assigned to each broadcasting station as shown in FIG.
The multi-tuning with the multi-tuned broadcasting signals f1, f2, f3 ,.

A frequency converter 35 is connected to the multi-tuning unit 34, and a local oscillator 36 is connected to the frequency converter 35.
Are connected. As a result, as shown in FIG. 3, in the frequency converter 35, the intermediate frequency component F of the difference between the broadcast signals f1, f2, f3 ... And the oscillation signal fo oscillated by the local oscillator 36.
1a, F2a, F3a ... Are taken out. An expansion unit 37 such as a frequency multiplication unit is connected to the frequency conversion unit 35, and as shown in FIG. 3, the broadcast signal F1 converted into an intermediate frequency component.
a, F2a, F3a ... Are expanded to F1b, F2b, F3b.

A single transmission line 38 such as a cable is connected to the expansion section 37 and transmits the broadcast signal of the intermediate frequency component to the retransmission section 39. A demultiplexing unit 40 including a plurality of filters is connected to the transmission line 38 to demultiplex the expanded broadcast signals F1b, F2b, F3b. Re-transmitters 19a, 19b ... Are connected to the demultiplexing unit 40, and frequency conversion of the intermediate frequency signals F1b, F2b, F3b ... Is performed to restore each broadcast signal to the original broadcast signal for power amplification. There is. A mixing unit 20 is connected to the retransmitters 19a, 19b ..., And the broadcasting signals output from the retransmitters 19a, 19b ... Are mixed and transmitted to the transmitting antenna 13.

In such a rebroadcasting device 30, when the receiving antenna 14 receives FM or AM broadcast radio waves of a plurality of channels sent from a plurality of broadcasting stations, the broadcast signal is filtered by the filter 32 and the high frequency amplifier 33. It is sent to the multi-tuning unit 34 via. The multi-tuning unit 34 multi-tunes with the broadcast signals f1, f2, f3 .... The broadcast signals f1, f2, f3 ... Are converted into intermediate frequency component broadcast signals F1a, F2a, F3a ... by the frequency conversion unit 35, and expanded by the expansion unit 37.
b, F3b ...

The broadcast signals F1b, F2b, F3b ... Are sent to the re-transmitters 19a, 19b ... via the single transmission line 38, and the broadcast signals are frequency-converted and power-amplified. The mixing unit 20 converts the converted broadcast signal back to the original broadcast signal.
To the transmitting antenna 13 as a mixed signal to broadcast in a weak area.

Therefore, in this rebroadcasting device, a plurality of broadcast signals are multituned and the number of transmission lines connecting the receiving part and the retransmitting part is reduced, so that installation work can be reduced.

Further, since the intermediate frequency signal is expanded, the structure of the demultiplexing unit for demultiplexing the intermediate frequency signal can be simplified.

[0028]

As described above, according to the present invention,
A receiving unit that receives broadcast waves of multiple channels, a re-receiving unit that power-amplifies the broadcast signals received by this receiving unit, and a transmitting antenna that radiates the broadcast waves to the weak radio wave area that receives the transmission signals transmitted by this re-receiving unit. In the re-broadcasting device including, the receiving unit is provided with a multi-tuning unit that performs multi-tuning with broadcast signals of a plurality of channels, and a frequency conversion unit that is connected to the multi-tuning unit and converts a frequency, The conversion unit is connected to a single transmission unit that transmits a frequency conversion signal, and the re-reception unit divides the frequency conversion signal transmitted by the transmission unit and a demultiplexing unit. Since a plurality of retransmitters for amplifying the power of each of the demultiplexed demultiplexed signals to return to the original broadcast signal and a mixing unit for mixing the output signals of the retransmitters and sending the mixed signals to the transmitting antenna are provided, Section and retransmit section Installation work such as transmission lines is reduced can be reduced.

Further, since the frequency converting section is provided with the expanding section for expanding the frequency converted signal, the broadcasting signal can be easily demultiplexed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a rebroadcasting device of the present invention.

FIG. 2 is a multi-tuning characteristic diagram of the multi-tuning unit in FIG.

FIG. 3 is an enlarged characteristic diagram of an enlarged portion of FIG.

FIG. 4 is a block diagram showing the overall configuration of a conventional rebroadcast device.

FIG. 5 is a block diagram showing an internal configuration of a conventional receiver.

[Explanation of symbols]

 10 Rebroadcasting device 11 Receiving unit 12 Retransmitting unit 13 Transmitting antenna 14 Receiving antenna 15 Demultiplexing unit 16a, 16b Receiver 17a, 17b Transmission line 18 Tunnel 19a, 19b Retransmitting unit 20 Mixing unit 22 Tuning unit 25 Frequency converting unit 26 Local transmission unit 30 Rebroadcasting device 31 Reception unit 34 Multi-tuning unit 35 Frequency conversion unit 36 Local transmission unit 37 Expansion unit 38 Transmission line 39 Retransmission unit

Claims (2)

[Claims] 1. A receiving unit that receives broadcast waves of a plurality of channels, a re-receiving unit that power-amplifies a broadcast signal received by the receiving unit, and a broadcast wave in a weak radio wave area that receives a transmission signal transmitted by the re-receiving unit. In a rebroadcasting device comprising: a transmitting antenna for radiating a signal, a multi-tuning unit for performing multi-tuning with broadcast signals of a plurality of channels in the receiving unit, and a frequency conversion unit for converting a frequency connected to the multi-tuning unit. And a single transmission unit for transmitting the frequency conversion signal to the re-reception unit is connected to the frequency conversion unit, and the re-reception unit has a component for demultiplexing the frequency conversion signal transmitted by the transmission unit. The wave section, a plurality of retransmitters that perform power amplification on the demultiplexed signals demultiplexed by the demultiplexer, and restore the original broadcast signal, and mix the output signals of the retransmitters to the transmitting antenna. And a mixing section for sending, A rebroadcasting device characterized by the above. 2. The rebroadcasting apparatus according to claim 1, wherein the frequency conversion section includes an expansion section for expanding the frequency conversion signal.