Its Mostly About The Receiver
Dynamic Range – Its About Optimal Gain Control
11
• Goal is to add enough gain to amplify the desired signal for
maximum converter resolution
• Hard when, signals are very weak and close to the noise floor
• Receiver controls to use:
• Preamplifier/Attenuator – base setting to get in the “ball park”
• AGC Time Constant – set to match characteristics of the desired signal
• RF Gain Control – manual adjustment to fine-tune AGC operation
• IP+ and similar controls – proprietary ”magic” to optimize AGC Loop to
reject de-sensitation effects due to adjacent signal interference
A/D
Digital
Proc.
(FPGA)
RF (Pre)
Amplifier
Bandpass
Filter
D/A
Digital
Osc.
AGC Loop, IP+
A/D Range
00..0
11..1
+
To Next Page
