| 摘要 |
In a radar receiver having automatic gain control (AGC) which can be set in 6 dB increments adjusted for each range cell in a next sweep on the basis of the AGC setting of each corresponding range cell in the present sweep, the magnitude of the larger of the in-phase (I) and quadrature (Q) components of the video signals of the present sweep from A/D converter (90,92), the status of present sweep and previous sweep A/D limit conditions, and a selected guardband, the level of the radar return signal is held within the dynamic range of the A/D converters (90,92). A pulse interference detection and signal replacement apparatus (100, 110, 150) utilizes data from the AGC generator (34) to form an 8-bit log magnitude representation (LOG MAG 108) of each range cell sample generated from a floating point exponent and reduced precision mantissa components to detect a range cell pulse of interference at a specific range M and causes replacement of the range cell sample with an interpolated value determined from the average of the radar return signals of adjacent sweeps at range M. The pulse interference detector (110) registers three successive values Y1, X, Y2 of the log magnitude representation (LOG MAG 108), averages the first and last, Y1, Y2, through an adder (118) and a shift (119), adds the average (Y/2) to a threshold (121), and compares the resultant sum with the second value X. If X exceeds the sum, a pulse interference detection signal (PID 130) is supplied to a floating point interpolator (150) to cause selection of average values. |
