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:
Jun. 25, 1991
Filed:
Jan. 05, 1989
Steven H Goode, Palatine, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An improved bias control circuit (FIG. 2) is disclosed for a radio receiver (122) used in a communication system wherein a signalling preamble is sent prior to sending other information. The bias circuit (140) rapidly determines the DC voltage level representing the average frequency of the received signalling preamble (215), develops a DC bias voltage (275) proportional to the error in frequency between the receiver and the transmitted signal, and then selectively applies this bias voltage to the series coupling capacitor (240) located between the receiver detector (121) and the receiver processing circuitry (123). The circuit is adapted for a 0.2 GMSK receiver in a TDMA communication system, where a known 1100 bit synchronization preamble is sent in each user's TDM time slot.