H - Electricity – 04 – B
Patent
H - Electricity
04
B
325/106, 331/32
H04B 1/26 (2006.01) H03B 21/02 (2006.01)
Patent
CA 1116700
A B S T R A C T Ultra-narrow-band system for communication between a transmitter device and a receiver device provided by locking both to a carrier signal from a radio broadcast station and synthesizing a precise local frequency at each device as a preset multiple of the frequency of the carrier. Such a system is usable in a multi-station alarm and status communica- tion system including a multiplicity of independent radio alarm transmitters whose various carrier frequencies are different from but phased locked to a local radio broadcast station, and a central alarm receiving station which employs a corresponding multiplicity of synchronous detectors. The detectors each have associated with them a synthesized local oscillator source which is also phase-locked to the same radio broadcast station used by the alarm transmitters. Both the alarm transmitters and the central receiver are thereby accurately referenced to a readily available local frequency source (the broadcast station). As a consequence, very narrow-band radio circuits may be employed and the receiver and transmitter bandwidth may be accurately matched to the information content of the alarm and status signal source to achieve high signal-to-noise ratio reliable transmissions. The disclosed apparatus is relatively immune to intentional or unintentional interference and will burn-through most conventional transmissions which may be transmitting on the same radio channel at the same time, without unduly bothering these other unrelated transmissions.
368821
Fetherstonhaugh & Co.
Martinez Louis
LandOfFree
Narrow band communication system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Narrow band communication system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Narrow band communication system will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-44336