Fast automatic gain control method

Abstract

The invention provides a method to fast automatic control gain, which comprises: setting threshold value for energy of input signal; determining the signal with strength over indication range of A / D converter according to threshold, reducing its energy by analog gain control; determining the controlled gain by comparing reduced signal energy and target energy to adjust the strength of input signal till achieving specific range. This invention makes signal receive system in WLAN has fast auto-control gain ability to achieve optimal receive effect.

Description

Technical field [0001] The present invention relates to the field of wireless communication, in particular to a method of fast automatic gain control. Background technique [0002] WLAN (Wireless Local Area Network) technology is one of the most promising technologies in the field of wireless communication in the new century. At present, WLAN technology has matured day by day and its applications have become more extensive. WLAN is a flexible data communication system. It sends and receives data wirelessly. The highest data rate it can transmit reaches 54M / bps. With the development of mobile 3G (third-generation mobile communications) hindered, the use of WLAN as an alternative to 3G has become the first consideration of various telecom operators. [0003] In WLAN communication, the strength of the signal received by the receiver will be affected by multiple factors such as the distance of the signal sender and receiver and the state of the signal transmission channel. Therefore,...

AI Technical Summary

Problems solved by technology

[0004] The principle of the AGC method in the WLAN communication in the prior art is generally: the existence of the signal is judged by detecting the strength of the input signal in a short period of time, and the gain of the system to the input signal is determined by using multiple detections and gradually approaching, and then the The signal is demodulated without grading the energy of the input signal, and different gain control processes are used for input signals of different energy levels. The disadvantage of this method is that it takes a long time and is difficult to apply to AGCs that require a higher speed. high environment

Moreover, it lacks the ability to discriminate low-intensity signals. In an environment with a small signal-to-noise ratio, the probability of false start is high, resulting in an increase in system power consumption.

Images