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:
Mar. 11, 1986
Filed:
Dec. 22, 1983
James S Butcher, Phoenix, AZ (US);
Charles G Rousch, Streamwood, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A programmable bias circuit for use with a data limiter circuit is described. The limiter and bias circuit are coupled to a portable data receiver which is adapted to communicate in a coded system. Frequency disparities between a transmitted word sync signal and the portable data terminal local oscillator signal will cause a DC offset voltage in the received data signal. The programmable bias circuit is controlled by a decoder within the portable data terminal. If the terminal is in an idle state, the programmable bias circuit will be set to rapidly follow offset voltage shifts until a transmitted word sync signal has been detected. After word sync has been detected, a slower, more stable time constant circuit is programmably activated for the duration of the digital data message. The fast time constant circuit is activated at the end of the received data signal.