vga design
Thanks for the paper. This theory I thonk I know. What I need now is a kind of troubleshooter....
There are 2 problems:
-first when I enter in the AGC with a signal generator, set the ref point for an output power of -10dBm and it works for inputs from -40 to -70dBm which is higher than expected. I would like to be able to reach level down to -90dBm.
-second, when I put the LNA+mixer+IQ demodulator before the AGC, the output is -28dBm for a 70dBm input which is 18dB less then expected. Does it have something to do with the noise beeing at some point higher than the signal and lowering the required gain?
Thanx for your help
Ghost