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IFF/SIF - Siemens 1990
Figure 2: monopulse antenna of the
secondary radar „Siemens 1990” without its cover
This secondary radar is used in the civil and military air traffic management and by the air defense radar systems. The radar got different designators and abbrevations:
- SSR: by the civil air traffic control (Secondary Surveillance Radar)
- SIF: by the military air traffic control (Selective Identification Feature)
- IFF: by the air defense systems (Identification Friend or Foe)
Figure 1: At this picture the IFF-
monopulse antenna
is mounted at the top of the primary radar antenna (ASR-910)
The characteristics of this system are standardisated by Eurocontrol.
| Specifications | |
|---|---|
| frequency: | 1030 / 1090 megahertzes |
| pulse repetition time (PRT): | synchronuous to the primary radar |
| pulse repetition frequency (PRF): | synchronuous to the primary radar |
| pulsewidth (PW): | depending on mode |
| receive time: | |
| dead time: | |
| peak power: | up to 2 kilowatts |
| average power: | up to 100 watts |
| displayed range: | up to 250 nautical miles |
| range resolution: | 500 m |
| beamwidth: | 10 degrees |
| hits per scan: | 3 ... 5 |
| antenna rotation: | synchronuous to the primary radar |
