The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 1985
Filed:
Dec. 10, 1982
Arman V Dolikian, Palatine, IL (US);
Motorola, Inc., Rolling Meadows, IL (US);
Abstract
A decoder for receiving and decoding a coded signal includes a particular frequency f.sub.o with a first and second amplitude. The first amplitude of the frequency f.sub.o is associated with the end of a first coded message while the second amplitude of the frequency f.sub.o is associated with the beginning of a second coded message. The decoder includes a receiver for receiving the coded signal, a tone detector circuit for detecting the frequency f.sub.o, a level sensor responsive to the receiver output, a function block for performing a command and a control unit responsive to the tone detector circuit and the sensor means. The tone detector and control unit operate in one of at least two possible states. In the first state the control unit causes the tone detector to respond to the first amplitude of the frequency f.sub.o. When the level sensor senses the second amplitude of the frequency f.sub.o the control unit responds by placing the tone detector circuit into its second state. In its second state, the tone detector circuit detects whether the level sensor was tripped by the frequency f.sub.o or by some other frequency. If the tone detector circuit detects the frequency f.sub.o, the control unit causes the decoder to end its decoding of the first message and begin the decoding of a second message. If the tone detector circuit in its second state fails to detect the frequency f.sub.o, the control unit returns the tone detector circuit to its first state so it may continue to decode the first amplitude of the frequency f.sub.o associated with the first coded message.