PPRuNe Forums - View Single Post - Air Asia Indonesia Lost Contact from Surabaya to Singapore
Old 13th Jan 2015, 19:51
  #1944 (permalink)  
ACLS65
 
Join Date: Jun 2009
Location: Midpines, CA
Posts: 56
It is also things like FTC and STC to reduce clutter and I am sure lots of digital processing now.

"Sensitivity Time Control (STC). This feature reduces the impact of returns from sea state. It reduces the minimum SNR of the receiver for a short duration immediately after each pulse is transmitted. The effect of adjusting the STC is to reduce the clutter on the display in the region directly around the transmitter. The greater the value of STC, the greater the range from the transmitter in which clutter will be removed. However, an excessive STC will blank out potential returns close to the transmitter.

Fast Time Constant (FTC). This feature is designed to reduce the effect of long duration returns that come from rain. This processing requires that strength of the return signal must change quickly over it duration. Since rain occurs over and extended area, it will produce a long, steady return. The FTC processing will
filter these returns out of the display. Only pulses that rise and fall quickly will be displayed. In technical terms, FTC is a differentiator, meaning it determines the rate of change in the signal, which it then uses to discriminate pulses which are not changing rapidly."

Radar Systems


island_airphoto
Anyone who wants to see radar freq. vs. rain can take a look here:
https://www.youtube.com/watch?v=RvTkVj5-uv0
This isn't POWER, it is FREQUENCY.
ACLS65 is offline