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:
Jul. 22, 2003
Filed:
Jan. 06, 2000
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 amplifier based on a level of an output signal which is derived by variably amplifying a receiving signal S (input signal). An AGC output signal S is detected by a detector circuit , then a detected voltage signal S is converted into a digital signal by an A/D converter to output it to a CPU . Then, the CPU generates a control signal S based on the detected voltage signal S , then an A/D converter converts the control signal S into the analogue signal, and then the signal is sent out to the gain variable amplifier to execute gain control. At this time, an RSSI detector portion detects an RSSI signal S corresponding to a transmitting signal level from the receiving signal S , and then the CPU sends out the control signal S stored at the time of preceding execution of the gain control when the RSSI signal S is 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.