Rupudska wrote:Probably not, since infrared detection in general isn't meant to be long range.
Well APFSDS flying at M.6. According to my calculation, is detectable at 19.5 km. For tank to tank or ground battle which usually take place at 3-5 km. Slower ATGM at M 0.5 However is detected at shorter range (2.8 km) due to lower IR emission
The IR Sensor that i use as baseline is FPA imaging infra red one 640x480 . Which work in 1-10 micron wavelength. and Specific Detectivity (D-star) of 8x10^11 cm-Hz^1/2/W
The interception range of the APS is 100 m.
The reason why i look at IR Detector is that Radar sensor appears to have kinda inconveniently large cooling load.
My calculations showed that in order to detect inbound APFSDS head on (2 Km range) and basically search the volume. Required emitted peak power of 2.3 Kilowatt , put FMICW processing to make the hardware light.. will put average emitted power of the radar in excess of 600 watt (900 to be more exact) Which make liquid cooling mandatory.
The infra red detector however, as i see have advantage that it could have smaller power requirement and probably heat load. Longer or comparable range to radar at smaller aperture (My model IRST only has 2 cm wide Aperture) Better angular resolution and potentially wide instanteneous field of view due to the "staring" Imaging Infra Red mode employed.
The downside is of course weather.. But i believe nobody will fire ATGM or APFSDS/ HEAT etc. during rain or in foggy condition or at least with good accuracy.
My APS Scheme will use the IRST as early warning sensor to cue the radar. Such scheme in my view, allow reduction in radar resources needed to search target, thus aperture size can be reduced and power requirement can be optimized. Target detection range can hopefully be reduced to something like 1 Km or even less. It will hopefully reduce cost of the system.
The "radar only" APS, cost around U$ 1.6 million for 4 radars. The munition cost U$ 9734 (FY-2005).
and yes that is way more expensive than ARENA. but because the target is APFSDS sooooo.
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Another design alternative is pretty much like Throphy. The radar of the system is unique that it operates at C-band. This band is a compromise between precision and search. Previously however i rejected this operational band because it cannot provide small enough beamwidth for tracking and search. Another reason is that my concern of "Multipath propagation" If the beamwidth hit the ground and mess the target tracking and guidance command transmission. The intercept munition will fail to achieve required performance (Deflect the APFSDS to the ground), even if it managed to tumble the inbound APFSDS
But then.. hey because it's the IRST that will do the whole angular tracking job.. while radar do ranging and sending command.. why not.
and of course.. putting seeker into the intercept munition ala quick kill but this will drive up the munition cost. Nonetheless this might add additional C-RAM capability.