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:
Aug. 03, 1993
Filed:
Oct. 05, 1990
Risto Vaisanen, Salo, FI;
Nokia Mobile Phones Ltd., Salo, FI;
Abstract
An automatic gain control circuit (AGC) in a receiver for a digital radio telephone. Most of the total gain control of the received signal is accomplished in the base band frequency sections, i.e. in the I and Q branches, where the signal amplification is controlled step by step, and only a minor part of the total gain control is performed in the RF stage. High amplification steps are formed with amplifiers (9a, 10a, 11a, 12a; 9b, 10b, 11b, 12b), wherein the desired amplifier is activated with a digitally controlled (A, B) multiplexer (13a, 13b), and low amplification steps are formed with a resistance attenuator (14a, 14b), in which a signal of desired level is selected by a digitally controlled (C, D, E) multiplexer (15a, 15b). In addition, the RF amplifier (2) has two amplification levels and the desired amplification is selected with a digital control (F). With the different digital control combinations (A, B, C, D, E, F) the entire gain control range required of the receiver can be covered.