Method, system and apparatus for automatic gain control in direct-conversion receiver

摘要

A wireless receiver automatic gain control system includes: a coarse amplification subsystem that receives and amplifies a carrier-modulated signal; a demodulator that generates a baseband signal from the amplified carrier-modulated signal; a fine amplification subsystem that amplifies the baseband signal; and a controller connected to the amplification subsystems. The controller: obtains a unified gain value for the amplification subsystems; based on the unified gain value, selects (i) one of a plurality of coarse gain values defining a set of coarse gain steps each spanning a plurality of unified gain steps, and (ii) one of a plurality of fine gain values defining a set of fine gain steps each spanning a single unified gain step; and sets (i) the gain of the coarse amplification subsystem to the selected coarse gain value, and (ii) the gain of the fine amplification subsystem to the selected fine gain value.

主权项

1. An automatic gain control system for a wireless receiver, comprising:
a coarse amplification subsystem configured to receive a carrier-modulated signal from an antenna and amplify the carrier-modulated signal; a demodulator connected to the coarse amplification subsystem and configured to generate a baseband signal from the amplified carrier-modulated signal; a fine amplification subsystem connected to the demodulator and configured to amplify the baseband signal; a controller connected to the coarse amplification subsystem and the fine amplification subsystem, the controller configured to:
obtain a unified gain value for controlling the coarse amplification subsystem and the fine amplification subsystem;based on the unified gain value, select (i) one of a plurality of coarse gain values defining a set of coarse gain steps each spanning a plurality of unified gain steps, and (ii) one of a plurality of fine gain values defining a set of fine gain steps each spanning a single unified gain step; andset (i) the gain of the coarse amplification subsystem to the selected coarse gain value, and (ii) the gain of the fine amplification subsystem to the selected fine gain value.