Emergency broadcast receiver
First Claim
1. An emergency broadcast radio receiver comprising:
- a signal detector circuit, when powered, adapted to detect a predetermined emergency broadcast signal;
a timing generator circuit adapted to couple a battery to the signal detector circuit to periodically power the signal detector circuit; and
a demodulator circuit, when powered, adapted to demodulate an audio signal modulated on a radio frequency signal at a tuning frequency;
wherein;
the signal detector circuit, on detection of the predetermined emergency broadcast signal, is adapted to couple the battery to the demodulator circuit to power the demodulator circuit; and
the emergency broadcast radio receiver is adapted to set the tuning frequency to one of a plurality of predetermined emergency bulletin frequencies on detection of the predetermined emergency broadcast signal by the signal detector circuit, a setting of the tuning frequency being dependent on a power of demodulated audio signal at each of the plurality of the predetermined emergency bulletin frequencies, wherein the audio signal modulated on the radio frequency signal on at least the one of the plurality of the predetermined emergency bulletin frequencies contains emergency bulletin information.
1 Assignment
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Accused Products
Abstract
Disclosed is an emergency broadcast radio receiver. The receiver can comprise a signal detector circuit adapted to detect, when powered, a predetermined emergency broadcast signal, and a timing generator circuit adapted to couple a battery to the signal detector circuit to periodically power the signal detector circuit. The receiver also can comprise a demodulator circuit adapted to demodulate, when powered, an audio signal modulated on a radio frequency signal at a tuning frequency. The signal detector circuit can be adapted, on detection of the predetermined emergency broadcast signal, to couple the battery to the demodulator circuit to power the demodulator circuit. Other embodiments are also disclosed.
14 Citations
14 Claims
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1. An emergency broadcast radio receiver comprising:
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a signal detector circuit, when powered, adapted to detect a predetermined emergency broadcast signal; a timing generator circuit adapted to couple a battery to the signal detector circuit to periodically power the signal detector circuit; and a demodulator circuit, when powered, adapted to demodulate an audio signal modulated on a radio frequency signal at a tuning frequency; wherein; the signal detector circuit, on detection of the predetermined emergency broadcast signal, is adapted to couple the battery to the demodulator circuit to power the demodulator circuit; and the emergency broadcast radio receiver is adapted to set the tuning frequency to one of a plurality of predetermined emergency bulletin frequencies on detection of the predetermined emergency broadcast signal by the signal detector circuit, a setting of the tuning frequency being dependent on a power of demodulated audio signal at each of the plurality of the predetermined emergency bulletin frequencies, wherein the audio signal modulated on the radio frequency signal on at least the one of the plurality of the predetermined emergency bulletin frequencies contains emergency bulletin information. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. An emergency broadcast system comprising:
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a transmitter adapted to broadcast a predetermined emergency broadcast signal; a further transmitter adapted to broadcast an audio signal modulated on a radio frequency signal; and a radio receiver, comprising; a signal detector circuit, when powered, adapted to detect the predetermined emergency broadcast signal; a timing generator circuit adapted to couple a battery to the signal detector circuit to periodically power the signal detector circuit; and a demodulator circuit adapted, when powered, to demodulate the audio signal from the radio frequency signal at a tuning frequency; wherein; the signal detector circuit, on detection of the predetermined emergency broadcast signal, is adapted to couple the battery to the demodulator circuit to power the demodulator circuit, and the radio receiver is adapted to set the tuning frequency to one of a plurality of predetermined emergency bulletin frequencies on detection of the predetermined emergency broadcast signal by the signal detector circuit, a setting of the tuning frequency being dependent on a power of demodulated audio signal at each of the plurality of the predetermined emergency bulletin frequencies, wherein the audio signal modulated on the radio frequency signal on at least the one of the plurality of the predetermined emergency bulletin frequencies contains emergency bulletin information. - View Dependent Claims (11)
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12. A method of demodulating an audio signal from a radio frequency signal, the method comprising:
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coupling a battery to a signal detector circuit so as to periodically power the signal detector circuit; detecting, by the signal detector circuit, when powered, a predetermined emergency broadcast signal; coupling, on detection of the predetermined emergency broadcast signal, by the signal detector circuit, when powered, the battery to a demodulator circuit to power the demodulator circuit; demodulating, by the demodulator circuit, when powered, the audio signal from the radio frequency signal at a tuning frequency; and setting the tuning frequency to one of a plurality of predetermined emergency bulletin frequencies on detection of the predetermined emergency broadcast signal, the setting of the tuning frequency being dependent on a power of demodulated audio signal at each of the plurality of the predetermined emergency bulletin frequencies, wherein the audio signal modulated on the radio frequency signal on at least the one of the plurality of the predetermined emergency bulletin frequencies contains emergency bulletin information. - View Dependent Claims (13, 14)
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Specification