US 2010/0073080 A1 · AUTOMATIC GAIN CONTROL CIRCUIT AND METHOD FOR AUTOMATIC GAIN CONTROL

Abstract

An automatic gain control circuit and method for stably maintaining received power in a mobile Internet system is disclosed. An efficient automatic gain control circuit structure is provided which uses no separate analog circuit elements in a process of detecting the level of a received signal. Therefore, it is possible to reduce a complexity of hardware, the size of the automatic gain control circuit and a manufacturing cost. Further, an automatic gain control (AGC) unit, which is made in a Fluctuating Gunn-Peterson Approximation (FGPA) type, performs an automatic gain control simply by referring to a lookup table based on the level of a received signal. Therefore, the present automatic gain control circuit can not only be more simply designed or modified than a conventional automatic gain control circuit, but also stabilize the level of the received signal simply without periodically checking the level of the received signal for the automatic gain control.

Claims23

Dependent claims

An automatic gain control circuit for a mobile Internet system comprising:

a first attenuator for attenuating a received radio frequency (RF) signal;
a mixer for converting an output signal from the first attenuator into an intermediate frequency (IF) signal using a phase locked loop (PLL);
an amplifier for amplifying the IF signal;
a second attenuator for attenuating the amplified IF signal;
an analog/digital converter (ADC) fr analog/digital (A/D)-converting an output signal from the second attenuator;
and
an automatic gain control (AGC) unit for obtaining an attenuation value based on the A/D-converted signal using a lookup table and outputting the obtained attenuation value to the first attenuator and second attenuator.

4 more elements

Dependencies are inferred from the claim text.

Automatic gain control circuit and method for automatic gain control

Life of this patent

Automatic gain control circuit and method for automatic gain control

Life of this patent

Abstract

Claims23