The United States recently held an exercise (Empire Challenge) to test and demonstrate the ability of recon and control aircraft to share digital data. A JSTARS and E-2 carrier based radar aircraft shared data with UAVs and ground users. Last year, the U.S. Air Force successfully tested a battlefield Internet system on an AC-130 gunship. This allowed the AC-130 crew to share videos from their sensors with other aircraft. The Empire Challenge exercise was partly to convince NATO allies to adopt this technology. Although expensive, some NATO nations are already doing so, and the U.S. wants to develop agreements so it's easier to develop communications gear that will talk to that from other countries.
For nearly a decade, the U.S. Department of Defense has been trying to develop equipment that would allow the aircraft (including UAVs) of all three services to be able to communicate digitally (as in a battlefield Internet). Work has been going on, to make this happen, for the last six years. Getting "battlefield broadband" to work has been a work in progress, just as it has been in the commercial sector (where progress has also been slow.)
Everyone (including NATO) is using the U.S. Air Force Link 16 data format for sending digital data over a wireless network. Three years ago, a test had an army UH-60A helicopter, a navy F-18 and an air force F-15E, sitting on the ground, sending and receiving digital data. A ground station was also tied into the network. The successful test demonstrated that all three services had successfully modified their communications gear to handle Link 16 data. This was followed by tests with the aircraft in the air, including an army UAV and an AH-64 helicopter gunship, followed by tests with aircraft firing weapons, using target data from another aircraft, or someone on the ground. By the end of the decade, the Department of Defense wants to have the capability for troops on the ground, to share targeting data (including live video), with aircraft, and vice versa. Sort of battlefield video conferencing, with weapons.
At this point, most of the effort is going into making the system reliable enough to withstand the rigors of combat situations. If the system isn't reliable enough, the troops won't use it. Simple as that. During World War II, the military first encountered high-tech gear that was simply ignored by the troops, because the stuff did not work, or work well enough to depend on in a life and death situation. Those attitudes have continued, and developers know that if their gear is not robust enough, it will be rejected (unofficially, of course) by the troops.
The Link 16 based battlefield Internet system would allow data fusion, with commanders and intelligence analysts seeing sensor data (basically high resolution video) from many aircraft (fighters, gunships, helicopters and UAVs) over a battlefield, and use all the information to best select targets and assign air and ground forces to attack most effectively. Currently, all the aircraft with high-res eyes on the battlefield require lots of radio chatter to share their data. This approach is slow, and subject to errors.
The data fusion can include date from other sensors. These include those collecting electronic transmissions (from radios, cell phones or even automobiles) and photo-reconnaissance pods (which use high rez, like 30 megapixel and up, digital cameras to take still pictures and immediately transmit them).