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:
Jan. 25, 2005
Filed:
Apr. 12, 2004
Yasushi Iwata, Kanagawa, JP;
Yasufumi Ichikawa, Kanagawa, JP;
Yasushi Iwata, Kanagawa, JP;
Yasufumi Ichikawa, Kanagawa, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A constant output signal can be achieved by controlling a gain variable amplifierbased on a level of an output signal which is derived by variably amplifying a receiving signal S(input signal). An AGC output signal Sis detected by a detector circuit, then a detected voltage signal Sis converted into a digital signal by an A/D converterto output it to a CPU. Then, the CPUgenerates a control signal Sbased on the detected voltage signal S, then an A/D converterconverts the control signal Sinto the analogue signal, and then the signal is sent out to the gain variable amplifierto execute gain control. At this time, an RSSI detector portiondetects an RSSI signal Scorresponding to a transmitting signal level from the receiving signal S, and then the CPUsends out the control signal Sstored at the time of preceding execution of the gain control when the RSSI signal Sis reduced below a predetermined threshold value S. In the weak received electric field strength, the control voltage for the gain variable amplifier is prevented reduction, and the proper automatic gain control can be made possible to thus achieve the good receiving characteristics.