Mixed-mode AGC loop

Abstract

The invention discloses a mixed-mode AGC loop and belongs to the field of electronic technology. The AGC loop comprises a VGA module, a peak detector, a variable speed integrator, a comparator, a counter, a threshold control module and a gain controller; the VGA module is connected with the peak detector, the variable speed integrator and the gain controller; the peak detector is connected with the VGA module and the variable speed integrator; a threshold controller is connected with the variable speed integrator; the variable speed integrator is connected with the peak detector, the threshold controller, the VGA module and the comparator; the comparator is connected with the counter and the variable speed integrator; the counter is connected with the comparator and the gain controller; and the gain controller is connected with the counter and the VGA module. By implementing analog and digital dual-mode control to the differential intermediate frequency signal gain, the invention leads the output signal amplitude of the VGA module not to be changed along with the change of the input signal thereof; and the circuit structure of the AGC loop is simple and flexible.

Description

technical field [0001] The invention relates to the field of electronic technology, in particular to a mixed-mode AGC loop. Background technique [0002] Automatic Gain Control technology (AGC, Automatic Gain Control) is widely used in various electronic systems to increase the dynamic range of the electronic system. An AGC is mainly composed of a variable gain amplifier (VGA, Variable Gain Amplifier) ​​and a detection control circuit; the detection control circuit is used to detect the amplitude of the VGA output signal, and generates a control signal through a certain algorithm to adjust the output gain of the VGA, so that The amplitude of the VGA output signal does not vary with its input. In the prior art, there are two implementation methods for the detection control circuit: one is to use an analog method to detect the peak value of the VGA output signal, and after the peak signal is low-pass filtered and amplified, it is fed back to the VGA, and then the VGA output s...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem that the analog detection control method cannot realize the control of a wide gain range, the AGC speed is slow, and the digital detection method sometimes cannot realize AGC, etc., the present invention provides a mixed-mode AGC loop, and the AGC loop includes a VGA module , peak detector, variable speed integrator, comparator, counter, threshold control block and gain controller;

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