Description of the radar set, tactical-technical characteristics
Figure 1: AR-1
|frequency:||2 750 … 3 050 MHz
|pulse repetition time (PRT):|
|pulse repetition frequency (PRF):||700 Hz|
|pulsewidth (τ):||1 µs|
|peak power:||2 × 650 kW|
|average power:||2 × 455 W|
|instrumented range:||70 NM (≙ 130 km)|
|hits per scan:|
|antenna rotation:||15 rpm|
The DECCA (later: Plessey) AR-1 is an 2-D terminal approach radar operating in the S-Band. The AR-1 was designed to meet both military and civil airfield approach control requirements.
AR-1 is a frequency diversity radar using two magnetron fitted transmitters and two receivers using a klystron as stable local oscillator, an a low-noise traveling wave tube (TWT) as RF-pre-amplifier. The AR-1 used an analog system for Moving Target Indication (MTI). It used many different display configurations, utilising the new Fixed Coil PPI-Display.
The antenna of the AR-1 was linearly horizontal polarised only. The innovative shape of the double curved reflector with cosecant-squared pattern was exemplary for many later radars, right up to the Watchman.
The AR-1 was installed on a number of international airports, e.g. in 1966 in Sofia, Bulgaria.