JPS61174267U - - Google Patents

Description

[Brief explanation of drawings]

1 and 2 are block system diagrams showing first and second embodiments of the audio demodulation section of an audio multiplex broadcasting signal transmitting/receiving apparatus which has not yet been devised, and FIG. 3 is a conventional audio multiplex television reception system. FIG. 4 is a block system diagram showing an example of the audio demodulation section of the machine, and FIG. 4 is a frequency spectrum diagram showing the television audio multiplex broadcasting system in the United States. 1... Frequency division multiplex signal input terminal, 7, 24
... Matrix circuit, 17, 18 ... Addition circuit,
19... Second difference signal output terminal, 20... Level adjuster, 23... Band limit circuit, 25... Second sum signal output terminal.

Claims (1)

[Claims for Utility Model Registration] (1) A stereo audio signal is transmitted using a main channel signal of a direct wave and a first sub-channel signal of a modulated wave, and at the same time, the main channel signal and the band of the above-mentioned sub-channel signals are transmitted. In an audio multiplex broadcast signal transmitting/receiving device that transmits and receives a second sub-channel signal obtained by modulating a carrier wave with a monaural audio signal, the audio signal of the left channel and the audio signal of the right channel are transmitted. and the first monaural audio signal as the main channel signal, and the signal obtained by modulating with the first difference signal between the left channel audio signal and the right channel audio signal as the main channel signal. 1 sub-channel signal, and a second monaural audio signal and a second monaural audio signal of the first monaural audio signal.
or a signal obtained by modulating with a second sum signal of the left and right channel audio signals and the second monaural audio signal, and transmitting them simultaneously as the second sub-channel signal; , a filter circuit that receives a signal transmitted from the transmitting device and separately waves the main channel signal, the first sub-channel signal, and the second sub-channel signal; a first demodulator that demodulates the first sub-channel signal to obtain the first difference signal; and a first demodulator that demodulates the second sub-channel signal separated by the filter circuit to obtain the second difference signal. a second demodulator for obtaining a signal or a second sum signal, the main channel signal separated by the filter circuit, the first difference signal from the first demodulator, and the first difference signal from the second demodulator; The sum signal of the left channel audio signal and the second monaural audio signal is outputted to the first terminal by adding and subtracting the second difference signal or the second sum signal, respectively. A transmitting/receiving device for an audio multiplex broadcast signal, comprising a strix means for outputting a sum signal of an audio signal and the second monaural audio signal to a second terminal. (2) The matrix means adds and subtracts the main channel signal separated by the filter circuit and the first difference signal from the first demodulator, respectively, to obtain the left channel audio signal and the difference signal. a matrix circuit that obtains a third sum signal consisting of the first monaural audio signal and a fourth sum signal consisting of the right channel audio signal and the first monaural audio signal; Utility model registration claimed in claim 1, comprising first and second adding circuits that separately add the second difference signal from the second demodulator to the third and fourth sum signals. A transmitter/receiver for audio multiplex broadcast signals. (3) The matrix means generates a signal obtained by separately adding and subtracting the second sum signal from the second demodulator to the first difference signal from the first demodulator. The audio multiplex broadcasting signal transmitting/receiving device according to claim 1, which is a matrix circuit that outputs the signal to the first and second terminals.