Feb 10, 2008 #1 P passerby Member level 3 Joined Jun 12, 2006 Messages 58 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,286 Activity points 1,694 In the transceiver circuits, what's the difference btw VGA (Variable Gain Amplifier) and AGC (Automatic Gain Controller) ? I'm confused..... Thanks.
In the transceiver circuits, what's the difference btw VGA (Variable Gain Amplifier) and AGC (Automatic Gain Controller) ? I'm confused..... Thanks.
Feb 10, 2008 #2 FvM Super Moderator Staff member Joined Jan 22, 2008 Messages 52,423 Helped 14,752 Reputation 29,786 Reaction score 14,101 Trophy points 1,393 Location Bochum, Germany Activity points 298,112 Re: VGA & AGC VGA + level detector + feedback loop = AGC
Mar 26, 2008 #3 jecyhale Advanced Member level 1 Joined Feb 19, 2008 Messages 401 Helped 54 Reputation 108 Reaction score 8 Trophy points 1,298 Location China Activity points 3,001 Re: VGA & AGC AGC will give a fixed amplitue output, but VGA only give gain. So uasualy, VGA is a part of AGC. For example VGA gain is form 10dB to 70dB. if you want a -20dB output, but he input is -70dB. So the gain will be 50dB auto contralled by AGC.
Re: VGA & AGC AGC will give a fixed amplitue output, but VGA only give gain. So uasualy, VGA is a part of AGC. For example VGA gain is form 10dB to 70dB. if you want a -20dB output, but he input is -70dB. So the gain will be 50dB auto contralled by AGC.
Mar 26, 2008 #4 khouly Advanced Member level 5 Joined Oct 20, 2003 Messages 2,350 Helped 461 Reputation 916 Reaction score 101 Trophy points 1,343 Location EGYPT Activity points 13,242 VGA & AGC agree with FVM , the VGA is a part of AGC loop the AGC loop is a feedback loop , which make the output ampliftude is always constant as the input chanege so it employ a VGA khouly
VGA & AGC agree with FVM , the VGA is a part of AGC loop the AGC loop is a feedback loop , which make the output ampliftude is always constant as the input chanege so it employ a VGA khouly