RADIO FREQUENCY RECEIVING APPARATUS, RADIO FREQUENCY RECEIVING METHOD, LSI FOR RADIO FREQUENCY SIGNAL AND LSI FOR BASE BAND SIGNAL
First Claim
1. A receiving method in which a received radio frequency signal is amplified by a radio frequency variable gain amplifier, the amplified signal is converted into an intermediate frequency signal, the intermediate frequency signal is amplified by an intermediate frequency variable gain amplifier, and the amplified intermediate frequency signal is demodulated,wherein a period of gain control for the radio frequency variable gain amplifier is set to be shorter than a period of gain control for the intermediate frequency variable gain amplifier.
3 Assignments
0 Petitions
Accused Products
Abstract
A receiving apparatus may achieve optimal RF and IF gain control while suppressing saturated amplification due to interference. The receiving apparatus includes an RF variable gain Amp that amplifies a received RF signal, a mixer that converts an output signal of the RF variable gain Amp into an IF signal, an IF variable gain Amp that amplifies the IF signal, a demodulator that demodulates an output signal of the IF variable gain Amp, and an AGC circuit. The AGC circuit sets a period of gain control for the RF variable gain Amp to be shorter than a period of gain control for the IF variable gain Amp when gains of the RF variable gain Amp and the IF variable gain Amp are controlled based on the output signal of the IF variable gain Amp.
11 Citations
24 Claims
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1. A receiving method in which a received radio frequency signal is amplified by a radio frequency variable gain amplifier, the amplified signal is converted into an intermediate frequency signal, the intermediate frequency signal is amplified by an intermediate frequency variable gain amplifier, and the amplified intermediate frequency signal is demodulated,
wherein a period of gain control for the radio frequency variable gain amplifier is set to be shorter than a period of gain control for the intermediate frequency variable gain amplifier.
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3. A receiving apparatus comprising:
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a radio frequency variable gain amplifier that amplifies a received radio frequency signal; a conversion circuit that converts an output signal of the radio frequency variable gain amplifier into an intermediate frequency signal; an intermediate frequency variable gain amplifier that amplifies an output signal of the conversion circuit; a demodulation circuit that demodulates an output signal of the intermediate frequency variable gain amplifier; and an automatic gain control circuit that sets a period of gain control for the radio frequency variable gain amplifier to be shorter than a period of gain control for the intermediate frequency variable gain amplifier, when gains of the radio frequency variable gain amplifier and the intermediate frequency variable gain amplifier are controlled based on the output signal of the intermediate frequency variable gain amplifier. - View Dependent Claims (4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
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16. An LSI for a radio frequency signal, comprising:
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a radio frequency variable gain amplifier that amplifies a received radio frequency signal; a conversion circuit that converts an output signal of the radio frequency variable gain amplifier into an intermediate frequency signal; and an intermediate frequency variable gain amplifier that amplifies an output signal of the conversion circuit, wherein a period of gain control for the radio frequency variable gain amplifier is set to be shorter than a period of gain control for the intermediate frequency variable gain amplifier, when gains of the radio frequency variable gain amplifier and the intermediate frequency variable gain amplifier are controlled based on an output signal of the intermediate frequency variable gain amplifier. - View Dependent Claims (17, 18)
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19. An LSI for a base band signal for connection to an LSI for a radio frequency signal including a radio frequency variable gain amplifier that amplifies a received radio frequency signal, a conversion circuit that converts an output signal of the radio frequency variable gain amplifier into an intermediate frequency signal, and an intermediate frequency variable gain amplifier that amplifies an output signal of the conversion circuit,
wherein the LSI for a base band signal comprises an automatic gain control circuit that controls gains of the radio frequency variable gain amplifier and the intermediate frequency variable gain amplifier under a condition where a period of gain control for the radio frequency variable gain amplifier is set to be shorter than a period of gain control for the intermediate frequency variable gain amplifier.
Specification