JPS61117932A - Fm stereo broadcast system in catv - Google Patents

Abstract

PURPOSE:To enjoy an FM broadcast without troublesome tuning by multiplexing a data of an FM broadcast channel at the center, demodulating it at a terminal device to use the result as a data for automatic channel selection of an FM tuner. CONSTITUTION:A data multiplexing encoder 19 is arranged at the center between a video/audio source 1 and a TVIF demodulator 2 and a data of a stereo broadcast channel corresponding to a channel of each TV broadcast signal is multiplexed in a VBI period of a video signal. Further, an output signal of a CATV terminal device 8 at a terminal device side is inputted to a stereo receiver 18, in which a data of a stereo broadcast channel multiplexed to a TV broadcast channel selected at present is demodulated by a multiplex data demodulator 15. Then the data is inputted to an FM tuner controller 16, which applies tuning to an FM tuner 17 into 84MHz, when the TV broadcast channel is Hch, for example, based on the said data.

Description

[Detailed description of the invention]

(Industrial Field of Application 1) The present invention relates to an FM stereo broadcast system in CATV1, in which audio is broadcast in FM stereo on a channel different from a video broadcast channel.

[Prior Art and Problem 1] As this type of FM stereo broadcasting system, the systems shown in FIGS. 1 and 2 are conventionally known. Here, on the center side, the video signal and audio monaural signal supplied from the video/audio source 1 are modulated by the TVIF converter I 2, and input to the IF scramble encoder 3 as the video ■F signal and the audio ■F signal. Ru. Here is the video I
The F signal is scrambled, and decoding information is multiplexed onto the audio [E signal]. This is then frequency-converted by the channel up converter 4 to, for example, l-1ch. On the other hand, the audio stereo signal output from the video/audio source 1 for stereo broadcasting is input to the stereo encoder 5, and FM audio conversion: lIIO2F
M modulated and IFf! The frequency is converted by the up-converter 97 to, for example, 84 MHz in the FM broadcast band. The output signals prepared in this way are combined and sent out together with other channel signals. On the other hand, on the terminal side, there is no communication from the main line! '3 L;t
It is split into TV frequency band and FM broadcast. The former is CA
TV terminal! 18, the latter being input to a stereo FM tuner 10. Audio amplifier 11. The signal is input to audio No. 141 consisting of speaker 12. When the viewer operates the terminal 8 to request (for example) -1ch, the converter 13 tunes Hch according to instructions from the controller 8a, and the signal is input to the scramble decoder 14. Since the scramble decoded information is multiplexed with the audio signal, here the controller 8a provides the decoded signal based on the data demodulated from the audio signal.
The descrambled TV signal is output and TV set 9
sent to. At this time, the viewer will listen to monaural audio on TV set 9. If the viewer requests stereo broadcasting, stereo F
84M corresponding to l-1ch by operating M tuner 10
When tuned to Hz, the speakers 12 provide stereo service. The problem here is that in order to receive stereo broadcasting service, each time you change channels on the CATV terminal, you must
Due to the need to tune the M tuner,
This is very inconvenient for viewers. [Means for Solving the Problems] The present invention has been made based on the above circumstances, and is a method of multiplexing data of an FM broadcast channel to a selected TV broadcast channel, demodulating this on the terminal side, and converting it into audio FM. The present invention aims to provide an FM stereo broadcasting system for CATV that uses a W4III tuner to automatically select a station so that a stereo service can be obtained. For this purpose, the present invention provides a system in which audio is broadcast in FM stereo on a channel different from a video broadcast channel, and the CATV center side transmits data of the FM broadcast channel performing stereo broadcast within the channel band of TV broadcast. The receiving side demodulates the data of the multiplexed FM broadcast channel within the band from the selected channel input via the CATV converter, and the FM receiver is set to the FM broadcast channel specified by the data. It is characterized by synchronization. (Embodiment) Hereinafter, an embodiment of the present invention will be explained in detail with reference to FIGS. 3 and 4. Here, the same components as in the prior art example will be designated by the same reference numerals. In the system according to the present invention, the center side
A data multiplex encoder 19 is arranged between the audio source 1 and the TV I F'a modulator 2, and multiplexes the data of the stereo broadcast channel corresponding to each TV broadcast signal channel into the VB1 section of the video signal. ing. Also, on the terminal side, the output signal of the CATV terminal 8 is received in stereo! 1iif18, and here the multiplexed data li
The modulator 15 modulates the data of the stereo broadcast channel multiplexed with the currently selected TV broadcast channel. Then, this is input to the FM tuner controller 16, and the FM tuner controller 16 selects the FM tuner based on the above data, for example, when the TV broadcast channel is Hch.
The tuner 17 is tuned to 84MH2. Similarly, when a viewer tunes into a TV channel that is broadcasting in stereo at 86MHz, the multiplexed data is "86MHz".
MHz", the FM tuner controller 1G selects the FM tuner 17 to 86M1-12. In the above embodiment, the multiplexed data is sent in the video VB1 section, but the audio is sent along with the scrambled data. It may be multiplexed with the signal.Also, a data carrier may be prepared within the broadcast channel band and data may be sent using this.Furthermore, the data to be sent is FM broadcast channel data, but this may be used as video The command signal may be composed of channel numbers, and the corresponding FM broadcast channels may be written as a table in the ROM or RAM in the FM tuner controller 16, and read out as a command signal to perform FM tuning. Effect 1 The present invention is as detailed above, and the center side
Since we multiplexed broadcast channel data and demodulated it on the terminal to use the FM tuner for automatic tuning, m*
Since i can obtain FM broadcasting service at the same time by selecting a TV station, it is possible to enjoy FM broadcasting without the hassle of tuning.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional center-side sending circuit, FIG. 2 is a block diagram of a terminal-side receiving circuit, FIG. 3 is a terminal-side block diagram showing an embodiment of the present invention, and FIG. 4 is a block diagram of the center. 1...Video/audio source, 2...TVIF change m@,
3...1F scramble encoder, 4...channel up converter, 5...stereo encoder,
6...FM audio conversion II, 7...up converter,
8...CATV terminal device, 8a...controller, 9
...TV top set 10..., stereo encoder,
11...Audio amplifier, 12...Speaker, 1
3... Converter, 14... Scramble decoder, 15... Multiplex data demodulator, 16... FM tuner controller, 17... FM tuner, 18...
Stereo receiving device, 19...data multiplex encoder. Patent applicant: Pioneer Co., Ltd. Agent: Patent attorney: Shin Kobashi Jundo Patent attorney: Susumu Murai Takue 6
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Claims (1)

[Claims] When audio is broadcast in FM stereo on a channel different from the video broadcast channel, the CATV center multiplexes the data of the FM broadcast channel that is broadcasting in stereo within the channel band of the TV broadcast, and the receiving side
It is characterized by demodulating the data of the FM broadcast channel multiplexed within the band from the selected channel input through the ATV converter, and tuning the FM receiver to the FM broadcast channel specified by the data. CA
FM stereo broadcast system on TV.