Some problems an adavantages with IR sensor based systems making them suitable for certain tasks more.
Since its passive it can be installed frontlines without being detected. Ofcourse satellites are a problem but continiously changing location, digital-pixelated-camouflage etc. can reduce that threat.
One disadvantage is mechanical scanning and single target engagement in most of these systems. Mechanical scanning may need queing by another system a radar for example to get the target in shorter time. For drones it is not necessary though since drones have audio signature and lower speeds-altitudes although they have lower ir signatures. Single target engagement is not a big problem if the system is used for point defense and not area defense considering the system is passive and not easily detectable from above.
Some high altitude short range weapons that can be used against drones or planes at frontlines that can be attached to these sensors:
this one is cheap and can be camouflaged and towed away by other vehicles. 120mm guns also exist having a higher altitude.
https://en.wikipedia.org/wiki/100_mm_air_defense_gun_KS-19
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For a missile a variant/local copy of 57E6 missile can do the job effectively in my opinion. I dont favor the pantsyr as a system with its shortcomings but its rocket can be modified to be taken out and attached to other local built systems.
The rocket weighs about 80kg and has 15000m altitude making it a man portable high altitude system if attached to a lightweight or towable electro optical sensor. High altitude stinger you may well call it.
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Medium range:
Systems scanning problem with IR-electro optical stations can be reduced with advance and improvement of ir focal plane arrays. Also laser range finder wont be necessary if 3 of such high performance passive sensors are used separated from each other just like GPS satellites. For high ir signature targets like jet fighters the target can be identified by all 3 sensors and the difference between them can compute azimuth, elevation and range of the target. It is just an idea but it can be experimented though in my opinion if you have high performance passive IR sensors. Somewhat similar to radio locator Kulchuga system but working in infrared mode instead of radio location mode.
The target data can be fed to low performance individual electrooptical systems to track and hit the targets by their own.
Other option is Radars in scanning mode can be made more LPI with known lpi methods like frequency hopping, keying etc. as it does not focus its energy to track individual targets. Rough target data can be fed to individual electro optical systems like the 50km example "sepehr 14" to track and make the kill shot.
Also laser range finder is limited to about 20km range. A radar range finder with a narrow sharp beam won't be detected by the enemy and won't have range limitation. You dont need to continiously open the range finder as well. After initial range data measurement and continious infrared signature update of the target the range can be estimated but with less accuracy depending on the IR sensor. But if the radar range finder beam is narrow enough you can keep it open as your position is not revealed without sacrificing accuracy.
