Laser-based data link

[popcorn]

I raised this question in the F-35 Variants sub-forum but this is it's proper place. So, why not build on the success achieved by HAVE LACE to develop laser-based links for airborne application i.e. A2A, A2G that offer high bandwidth capacity and robustness in an EW environment which will likely be prevalent in future conflict?

A.5 AIRBORNE LASER DATA LINKS

Modern battlefield strategy is predicated on knowing where the enemy’s (or potential enemy’s) assets ore located and their operational capability. This vital information is constantly being gathered and updated by various ground, space, and airborne sensors. The requirement to send ever increasing amounts of tactical military information between sensor aircraft and information processing facilities has begun to press the limits of present airborne data links, even when data compression techniques are used. Therefore, utilization of optical data links is being considered as a possible solution. The feasibility of laser airborne data links was demonstrated in the mid-80’s by the U.S. Air Force Research Laboratory HAVE LACE (Laser Airborne Communications Experiment) Program. This program developed and tested two laser communications terminals that operated at 19.2 kilobits/sec. The terminals were tested using two KC-135 aircraft that nominally flew at 20,000 to 25,000 feet (ft) altitudes with separation distances out to 160 km. The most significant result of the HAVE LACE flights was the difficulty of initial signal acquisition between the two moving platforms, since it had to be performed manually. However, once signal acquisition was accomplished, tracking proved to be robust and communications performance was consistently measured at 10-6 Bit Error Rate (BER) or better. Since the HAVE LACE program, laser terminal development and data rates have improved dramatically. Therefore, various research programs have been undertaken in order to fully exploit the potentials of this technology, mainly for spaceborne and airborne applications. Another U.S. Air force program is currently ongoing to develop a wideband laser data link operating at 810 and 852 nm. In September 1995, the program successfully ground demonstrated a 1.1 gigabit/second full duplex data link over a distance of 150 km (Hawaii Islands). Successively, the system used in the ground demonstration was redesigned and installed in two jet aircraft for flight demonstration at distances up to 500 km. The demonstration flights, performed in September 1998, were successful and proved the ability of the system to communicate in the upper atmosphere to 500 km with a BER of 10-6. The tests also provided data on atmospheric attenuation and beam scintillation. Furthermore, data on the effects of aircraft airflow upon beam steering were also collected. These data, and the information obtained from similar developments, are now being used for other laser communication development efforts (e.g., an air-to-space capability

[KamenRiderBlade]

I would say it depends on which aircraft / vehicles are using it.

It makes sense on certain aircraft, not all.

AWACS to any ground units makes alot of sense.

AWACS to any slower moving aircraft that won't have to dodge alot makes alot of sense.

Laser based Data Links to fighters seem highly impractical if they have to suddenly move to dodge, bam, you lost your connection.

[fiskerwad]

I would say it depends on which aircraft / vehicles are using it.

It makes sense on certain aircraft, not all.

AWACS to any ground units makes alot of sense.

AWACS to any slower moving aircraft that won't have to dodge alot makes alot of sense.

Laser based Data Links to fighters seem highly impractical if they have to suddenly move to dodge, bam, you lost your connection.

I would say that steering the beam would seem very doable given the current technology. Locking the laser to a receiver aircraft may already be in place?
fisk

[KamenRiderBlade]

I would say it depends on which aircraft / vehicles are using it.

It makes sense on certain aircraft, not all.

AWACS to any ground units makes alot of sense.

AWACS to any slower moving aircraft that won't have to dodge alot makes alot of sense.

Laser based Data Links to fighters seem highly impractical if they have to suddenly move to dodge, bam, you lost your connection.

I would say that steering the beam would seem very doable given the current technology. Locking the laser to a receiver aircraft may already be in place?
fisk

I concur, but it makes more sense to have a Laser link on aircraft that aren't going to be barrel rolling or hard banking.

Since there are plenty of aircraft in the fleet that isn't a fighter, there should be plenty of use for it.

If you put it on a fighter, the only use I can see is getting data before a fight starts in a heavily jammed environment.

[ford2go]

Couple of things -- although I'm certainly no expert.

Would laser comm be detectable? Since we use lasers to paint targets, I wonder if these lasers might be somewhat detectable. If you're callling up something stealthy, that would be bad.

19.2 K bits/sec (1.2 mbits/min) does not seem that fast -- hopefully that's improved. I think that modern cell phones operating as wifi hotspots can do better.

hj

[avipost]

[quote="ford2go"]Couple of things -- although II agree with ford2go...

In a sensitive environment messaging would need to be secure & real time. 19.2 kbps seems very slow for mission-critical transmissions.

Surely a broadband option for comms would be more reliable, faster at 64kbps ISDN with streaming IP data rates up to 256 kbps? I too am no expert, but have seen solutions such as these on http://www.isr.aero/inmarsat-swiftbroadband which is interesting as it seems to address the issue