US 11,929,770 B1
Automatic Gain Control (AGC) for On-Off Shift-Keying (OOK) receiver
Yat Tung Lai, Hong Kong (HK); Lu Chen, Hong Kong (HK); Wuxue Ni, Shenzhen (CN); and Huimin Guo, Hong Kong (HK)
Assigned to Hong Kong Applied Science and Technology Research Institute Company Limited, Hong Kong (HK)
Filed by Hong Kong Applied Science and Technology Research Institute Company Limited, Hong Kong (HK)
Filed on Mar. 6, 2023, as Appl. No. 18/118,118.
Int. Cl. H04B 1/04 (2006.01); H04B 1/7176 (2011.01)
CPC H04B 1/04 (2013.01) [H04B 1/7176 (2013.01); H04B 2001/0416 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A receiver with non-continuous Automatic Gain Control (AGC) comprising:
a front end having a Low-Noise Amplifier (LNA), a Low-Pass Filter (LPF), and a Programmable Gain Amplifier (PGA) in series to amplify a received signal applied to an input of the LNA to generate an amplified output, wherein a gain of the front end is adjustable in response to a gain setting;
a rectifier that rectifies the amplified output from the front end to generate an output voltage;
a data converter that receives the output voltage from the rectifier and generates binary data;
a frame detector that receives the binary data from the data converter and activates a framing signal that is synchronized to frames of the binary data;
a level detector that compares the output voltage from the rectifier to a first threshold to generate a first compare result and to a second threshold to generate a second compare result, wherein the second threshold is greater than the first threshold; and
an AGC controller that is activated for a new frame by the framing signal from the frame detector, the AGC controller initializing the gain setting to a maximum gain in response to the framing signal, the AGC controller decreasing the gain setting in response to the first compare result and the second compare result, the AGC controller locking the gain setting when the first compare result and the second compare result indicate that the output voltage is between the first threshold and the second threshold,
whereby the gain setting is adjusted in response to the framing signal and locked until the AGC controller is activated again for a next new frame.