ASR 12
Description of the radar set, tactical-technical characteristics
Figure 1: ATC-Radar ASR 12 (© Northrop Grumman)
| Specifications | |
|---|---|
| frequency: | 2.7 to 2.9 GHz |
| pulse repetition time (PRT): | processor controlled |
| pulse repetition frequency (PRF): | |
| pulsewidth (τ): | 1 µs and 55 µs |
| receive time: | |
| dead time: | |
| peak power: | 22 kW |
| average power: | |
| instrumented range: | 60 / 80 / 100 NM |
| range resolution: | 700 ft |
| accuracy: | |
| beamwidth: | 1.4 degrees |
| hits per scan: | |
| antenna rotation: | 10 / 12 / 15 rpm. |
| MTBCF: | > 37 500 h |
| MTTR: | < 0.25 h |
ASR 12
The Northrop Grumman ASR 12 is a modular, fully solid-state S-Band radar system that incorporates the latest technologies in airport surveillance radar systems. It is a further development of the ASR 9 and also uses the same reflector, a curved metal latticework 36 feet wide and 17 feet tall.
Weather conditions detected by the ASR 12 are measured in six levels of intensity conforming to the ICAO standards and are processed using a weather channel processor separate from the aircraft channel.
The operation of the ASR 12 is depicted as a simple “state diagram.” There are two major transitions that occur during each pulse period:
- Short to long pulse transition in high beam
- High beam to low beam transition using the long pulse
These transitions are adjustable to allow optimization of the radar operation in the clutter conditions of the site.
receiver
receiver
divider
Figure 2: Radarantenna with high- and low- beam pattern
Figure 2: Radarantenna with high- and low- beam pattern
range
range
range
Figure 3: Example of radar timeline with different pulse-durations
In the lower elevation the radar radiates a number of „Short-Range-Pulses” in series.
This is required for
pulse-pair processing
practicable in close-up range only.
range
range
range
Figure 3: Example of radar timeline with different pulse-durations
In the lower elevation the radar radiates a number of „Short-Range-Pulses” in series.
This is required for
pulse-pair processing
practicable in close-up range only.