Evaluation of New Model of Air Route Surveillance Radars
1975 Volume 1975 Issue 12 Pages 1-42
Details
1975 Volume 1975 Issue 12 Pages 1-42
Evaluation of new model of air route surveillance radars has been conducted, intending to study the adaptability to requirements of CAB's en-route traffic control automation program phase II.
The radar system is designed to improve the credibility of primary radar by reducing the number of spurious targets and increasing its capability to detect aircrafts in the presence of precipitation and ground clutter. For this purpose, many new techniques are introduced. These are high power klystron amplifier, two-beam antenna system, RF-STC and LOG/CFAR.
The evaluation has been carried out placing importance on the performance test of newly adopted techniques.
Two-beam antenna system provides 10 to 20 dB better target signal-to-clutter signal ratio than single-beam one. Performance of LOG/CFAR is measured by gated noise signal as the simulated precipitation clutter. LOG/CFAR reduces precipitation clutter down to the receiver noise level and weak signal of an aircraft target, only 2 dB greater than precipitation clutter, can be discriminated above the receiver noise level up to 60 dB. Klystron improves subclutter visibility by 3 to 4 dB over existing magnetron radar.
Since the aircraft used in the test is small and the flight at high altitude is impossible, measurement of the vertical coverage is made inserting an attenuator before receiver head to reduce the coverage.
Flight test has been made to study following items: the error due to measurement of blip intensity on PPI, the error due to fluctuation of aircraft heading, and the effect of ground reflection on coverage.
