Automatic gain control for digital radar intercept receivers

摘要: An automatic gain control (AGC) circuit for electromagnetic wave receiving systems, such as radar warning receivers, has a number of N parallel paths to which analog IF input signals are applied with each path being connected one inputs an output switch. Each contains free running sampling analog-to-digital converter (ADC) that digitizes amplified input, the digitized digital delay units whose supplied switch's inputs. The amplification in is fixed and staggered provide different amplifications ADCs. AGC leading edge trigger (LET), trailing (TET) track-and-hold samples holds amplitude pulse starting at demarked by LET. Writing signal from ADCs into started stopped based on pulse's LET TET. A TET activates compares sampled held references levels selects setting amongst produced largest version without ADC over-range. then sets switch selected reads data out pulse-to-pulse signal.