"Hobo" wrote in message
...

I tried asking this question before and got zero responses;(


This NG loves to talk about whether or not stealth aircraft can be
detected. What about the issue of detecting SAM radar? If LPI, or
Quiet
Radar techniques are used on the ground radars guiding SAMs this
will
make it difficult to find and destroy the radars. Similarly, if the
same
pseudo-random noise techniques are used for the datalink the SAMs
guidance will be harder to jam.

If one cannot bomb SAM radar or jam the datalink than flying in
enemy
airspace becomes vastly more difficult. The basic ideas behind LPI
radar
seem to come from the same information theory behind much of the
cell
phone industry so the knowledge base is widespread.


Most modern SAM guidance techniques are heading towards an active
homing system. The French have a common active hommer on the AAM
mica and the SAM aster. The SAM is launched preloaded with the
co-ordinates and velocity of the target and the missile guides itself
using an inertial guidance system to the vicinity of the target at
which point the radar lights up. Usually a data link is also
available for midcourse corrections. In the case of AMRAAM there is I
believe only 1 midcourse update provided if at all.

In this way:
1 The command link can be of low bandwidth and is easily given the
characteristics of security and LPI. It is not neccesary to provide
feedback to the missile since it has an inertial guidance system.
2 Little warning is given since there is no tracking and illuminating
radar 'spiking' the target.
3 Jamming and stealth against the missile is less effective as the
radar's illuminating power increases as the missile active radar
approaches.
4 Multiple missiles can be launched.

The next stage of radar appears to be impulse radar. This AFAIKS
requires cryogenics. It consists of sequences of impulses of around 1
wavelength that contain broad spectrums of frequencies that can excite
any resonance's within a stealth structure. It also is extremely
capable of resolving chaff or terrain like ocean waves and ripples.