Smoke, mirrors and the GBU - 12

Yesterday I read two articles on laser assisted
bombing which were quite satisfying but still
managed to leave me wondering about the technology
and the possibility of employing countermeasures
during weapon delivery.
Without giving away any "state secrets" perhaps
someone on rec.aviation,military could dispell
my idle thoughts on future possibilities?

In description of F15 strikes in Afghanistan
one author described instances where cloud cover
prevented the AC from lasing ground targets.
Numerical recognition codes required by the
F15 mounted laser and its bomb were relayed
by pilot voice (encrypted?) to well trained
FACs on the ground who punched the codes into their
man portable units. The GBU-12s were dropped
and completed flight under control of the FACs
using battery powered lasers aimed at their
targets, usually armour.

Question - how many times per second is the
recognition code transmitted on the beam or
is it continuous? When the laser is reflected
off of the target how widely dispersed does
the beam become and what happens to information
encoded in the laser beam? (If I am not
understanding the process, please explain.)
Assuming that countermeasures
are designed for a particularly costly and
sensitive military asset, what would be the
approximate configuration of kit designed to
acquire the beam, decode the signal, and turn
on countermeasures to make the bomb miss?
....because of course you cannot stop F15s from
flying or their bombs from being dropped.

Thankyou.

"Xenia Dragon" wrote in message
om...

snip
Question - how many times per second is the
recognition code transmitted on the beam or
is it continuous? When the laser is reflected
off of the target how widely dispersed does
the beam become and what happens to information
encoded in the laser beam? (If I am not
understanding the process, please explain.)

The laser light is a carrier, just like a radio signal. The easiest way to
modulate information onto a laser is acoustically.

Assuming that countermeasures
are designed for a particularly costly and
sensitive military asset, what would be the
approximate configuration of kit designed to
acquire the beam, decode the signal, and turn
on countermeasures to make the bomb miss?

A laser is very directional and intercepting the signal would require you to
be in line of sight between the laser and the designated target. This may
not be a survivable place to be, as you are now lased.

...because of course you cannot stop F15s from
flying or their bombs from being dropped.

Some have tried.

"Tarver Engineering" wrote in message
...

The laser light is a carrier, just like a radio signal. The easiest way
to
modulate information onto a laser is acoustically.

Please explain what you mean, surely acoustics constitutes information and
not a modulation method? I'd have thought the easiest way to encode
information onto a laser carrier would be pulse-code modulation.

Si

(Xenia Dragon) wrote in message . com...
Yesterday I read two articles on laser assisted
bombing which were quite satisfying but still
managed to leave me wondering about the technology
and the possibility of employing countermeasures
during weapon delivery.
Without giving away any "state secrets" perhaps
someone on rec.aviation,military could dispell
my idle thoughts on future possibilities?


A followup note - Steve Davies page on the Strike Eagles
has a text only "Links to Strike" page which contains the
most detail I can find concerning F15 coordination with
Special Forces and FACs in Afghanistan. There is description
of the electronics including the security of communication
and maintaining integrity of the laser guidance, but still
I cannot find answers that I seek.
Mark Bowden's article THE KABUL-KI DANCE in 2002 on
the 391st FS is a must read, by the way.

Cheers. Xenia

"Xenia Dragon" wrote in message
om...
(Xenia Dragon) wrote in message
. com...
Yesterday I read two articles on laser assisted
bombing which were quite satisfying but still
managed to leave me wondering about the technology
and the possibility of employing countermeasures
during weapon delivery.
Without giving away any "state secrets" perhaps
someone on rec.aviation,military could dispell
my idle thoughts on future possibilities?


A followup note - Steve Davies page on the Strike Eagles
has a text only "Links to Strike" page which contains the
most detail I can find concerning F15 coordination with
Special Forces and FACs in Afghanistan. There is description
of the electronics including the security of communication
and maintaining integrity of the laser guidance, but still
I cannot find answers that I seek.
Mark Bowden's article THE KABUL-KI DANCE in 2002 on
the 391st FS is a must read, by the way.

You probably will find what you seek is classified information.