Digital signal transmitting and/or receiving system

Claim 2

A digital signal transmitting system comprising: means for generating a word synchronizing signal; means for generating digital audio signals sampled at a sampling frequency and coded in a predetermined data length; means for generating service bit signals including an identifying signal indicating that an emergency broadcast signal is being transmitted; means for mutiplexing said word synchronizing signal, digital audio signals and service bit signals so as to produce a digital word signal; a cable television transmission line; and means for modulating a carrier in accordance with said digital word signal and transmitting the modulated carrier through said cable television transmission line.

Claim 3

A digital signal transmitting system according to claim 1, in which said digital audio signals include at least a 2 channel stereo broadcast signal and an emergency broadcast signal.

Claim 4

A digital signal receiver comprising: a signal input terminal for receiving a modulated carrier modulated by a time-multiplexed word synchronizing signal, digital audio signals and service bit signals, said service bit signals including an identifying signal indicating than an emergency broadcast signal is being transmitted; means for demodulating said time division-multiplexed word synchronizing signal, digital audio signals and service bit signals; a speaker, an audio amplifier connected to said speaker; means for digital-to-analog-converting said digital audio signals into analog signals which are supplied to said speaker through said audio amplifier; a television receiver connected to said signal input terminal so as to receive a plurality of channels; means for latching said service bit signals; and control means connected to said latching means so as to produce a control signal which is supplied to said television receiver to turn on said television receiver when said identifying signal is received.

Claim 5

A digital signal receiver comprising: a signal input terminal for receiving a modulated carrier modulated by a time-multiplexed word synchronizing signal, digital audio signals and service bit signals, said service bit signals including an identifying signal indicating than an emergency broadcast signal is being transmitted; means for demodulating said time division-multiplexed word synchronizing signal, digital audio signals and service bit signals; a speaker, an audio amplifier connected to said speaker; means for digital-to-analog-converting said digital audio signals into analog signals which are supplied to said speaker through said audio amplifier; a television receiver connected to said signal input terminal so as to receive a plurality of channels; means for latching said service bit signals; and control means connected to said latching means so as to produce a control signal which is supplied to said television receiver to turn on said television receiver when said identifying signal is received.

Claim 6

A receiver according to claim 3, in which the channel of said television receiver is changed over by said control signal from said control means to receive a predetermined channel.

Claim 7

A receiver according to claim 4, in which said predetermined channel receives said emergency broadcast signal.

Claim 8

A receiver according to claim 3, in which said control means comprises a microcomputer.

Claim 9

A receiver according to claim 3, in which said control means produces a muting control signal which is used to prevent an analog signal from being transmitted to said speaker.