AN/FPS-20
Description of the radar set, tactical-technical characteristics
| Specifications | |
|---|---|
| frequency: | 1 280 … 1 350 MHz |
| pulse repetition time (PRT): | 2 858 µs |
| pulse repetition frequency (PRF): | 350 Hz |
| pulsewidth (τ): | 2 µs |
| receive time: | |
| dead time: | |
| peak power: | 2 … 2.5 MW |
| average power: | 4.35 … 6 KW |
| instrumented range: | 231 NM (≙ 428 km) |
| range resolution: | 1000 Yard |
| accuracy: | |
| beamwidth: | 1.3° |
| hits per scan: | |
| antenna rotation: | 3.3, 5 or 10 rpm |
| MTBCF: | |
| MTTR: | |
AN/FPS-20
The AN/FPS-20 was a widely used L-Band early warning and ground-controlled interception radar system, developed by Bendix orporation. The radar family started with the AN/FPS-3 in 1950, used a transmitter with two magnetrons.
The production of AN/FPS-20 began in 1956 with a dual-channel liquid-cooled klystron transmitter. Each receiver used the “Dicke Fix”- processing. The antenna was equipped with a polarizer and could work alternating in circular or linear horizontal polarization.
Later updates (including anti-jamming opportunities mostly) led to the designations AN/FPS-64, AN/FPS-65, AN/FPS-66, AN/FPS-67, AN/FPS-91, AN/FPS-93, AN/FPS-100, AN/FPS-113 and AN/GPS-4. The Canadian vwesion got the designator AN/FPS-508.
| Radar Redesignations | ||
|---|---|---|
| Original System | + Upgrade | = New System |
| AN/FPS-20 | + AN/GPA-102 | = AN/FPS-64 |
| AN/FPS-20 | + AN/GPA-103 | = AN/FPS-65 |
| AN/FPS-20A | + AN/GPA-102 | = AN/FPS-66 |
| AN/FPS-20A | + AN/GPA-103 | = AN/FPS-67 |
| AN/FPS-20 | + OA-7091/FPS | = AN/FPS-100 |
Similar upgrades using a Canadian OA-4831 system produced the AN/FPS-87 and AN/FPS-87A. A more major update was the adding of a new antenna from Raytheon, the Diplex Gating Unit (DGU), a bandpass filter and other modifications, to produce the AN/FPS-91 and 91A. The similar MK-748 applied to the -60 series resulted in the AN/FPS-64A, -65A, -66A and -67A. The radar AN/FPS-66A was also used by the FAA as en-route radar and got the designator ARSR-66. Canadian AN/FPS-87s were also converted, becoming AN/FPS-93 and 93A.
