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The Mobile Internet You'll Be Using In 10 Years
mr sanjeev writes "After being plagued with project overruns and a scaling back of the final system, the US military's next-generation satellite communications network is another step closer to reality, with completion of the payload module for the third and final Advanced Extremely High Frequency (EHF) satellite ... If GPS and remote imaging (think Google Earth) have proven anything, it is that technology initially developed for military purposes, and extremely expensive for initial civil use, will eventually reach the point where it forms part of our daily lives without us ever being conscious of the massive investment to get to that point."
More important, how's the latency? The RTT to a satellite in geosynchronous orbit is pretty high (especially considering that when requesting data, you have to double the RTT vs. streaming). The article doesn't seem to say if this is high-, low-, or medium-earth orbit.
Low earth orbit can get you RTT to the satellite of ~13 milliseconds at 2000 km, adding ~26 ms to the average page load, whereas a geosynchronous orbit could take ~240 milliseconds, adding ~480ms to a page load - quite a difference. Of course, these are optimal times, assuming the satellite is directly overhead.
That said, it does mention a constellation of three satellites, and there's no way that this could be practical with three satellites in a low- or even medium-earth orbit that I can see. Bandwidth is great, but latency is killer.