There’s nothing to screw up a day like bad Internet access. Email generally can stumble in and out even over a bad connection. Web surfing is a disaster. Three or four tries to get a page to load at all; graphics missing; strange browser behavior; everything takes six times as long as it’s supposed to and some things can’t get done at all. If you use satellite Internet access in the Northern United States, you’re in for a lot of bad days.
As I posted before, Mary and I use WildBlue satellite service at a camp we have on Lake Champlain. It was all we could get other than dialup so we did it. I did know when I ordered the service that it wouldn’t work in heavy rain or snow; that’s true even of satellite TV (which we also have). What I didn’t realize is that it is effectively a weather radar with a three hundred mile range. Our packet loss is directly correlated with the number of storms located south of us. Here’s this morning’s weather map (after six attempts to get it to load):
Our camp is at the red X. See those storms in northern New Jersey and southeastern New York. They’re blocking our signal!
How, you ask, isn’t the earth curved?
Well, yes it is. And that’s part of the problem. Satellite Internet access for fixed locations (eg. houses, not boats) is implemented with geostationary satellites – satellites which always appear to be at the same spot in the sky. There’s a good reason for this: it allows your dish to be pointed right at the satellite so that your transmit power can be much, much lower than if the satellite were moving through the sky and you had to radiate a signal in every direction (or have an antenna which tracked satellites). Moreover, with directional transmission, the same frequencies can be used over and over again.
For reasons Isaac Newton explained on his blog (no link available), these geostationary satellites have to be 22,000 miles above the equator in order to be moving exactly fast enough not to fall and exactly slow enough not to fly off into space and to appear motionless from earth. But the equator is a long way south of here. Note the angle of my dish – it’s not pointing up.
By now you’ve probably figured out part of the problem. The dish is at the perfect angle to detect the tops of thunderstorms way south of here. Doesn’t matter if weather.com won’t load; my satellite dish is my weather radar.
The further north you are, the more atmosphere between you and your satellite and the better the chance that a storm’ll get in the way. In fact, this particular satellite is southwest of me so even more atmosphere to try to look through.
This whole problem is exacerbated by the frequencies used for satellite service. In general, the lower the frequency the better the signal gets through stuff, think AM radio in the 540 to 1650 KHz ( a kilohertz is a thousand jiggles per second on a graph) range. AM works inside and it works in the rain.
Satellite TV, also sent from geostationary orbit, is generally at a frequency of 3.7 to 4.4GHz (a gigahertz is, you guessed it, a billion jiggles per second). It doesn’t work in severe local precipitation but generally gets through because the transmitter in the sky is really big and you don’t have to send anything back.
Before WildBlue, satellite Internet access providers (mainly HughesNet) used frequencies in the 11.7 to 12.7 GHz range. This is not a great frequency for this purpose, In fact, weather radars often operate in the slightly LOWER frequency range between 8.20 and 12.4 GHz. This frequency was chosen for weather radar because it DOES bounce off rain.
WildBlue boasts that it is at 29.5-30GHz. This is in the Ka band commonly used for radar guns. Remember that higher frequency means LESS ability to go through stuff. I haven’t compared HughesNet and WildBlue when there are storms to the south of us (or any other way). My guess is HughesNet would be slightly better but still extremely annoying.
Of course WildBlue marketing sees the high frequency as a benefit: “WildBlue uses Ka-band ‘spot beam’ satellites to allow multiple re-use of the same frequency, providing higher capacity at lower cost compared to other available satellite systems.” High frequencies do focus well (see radar guns above) but that’s a cost advantage to the provider. From the subscriber’s point of view, the signal is more often degraded than at lower frequencies. Bad tradeoff, specially since WildBlue isn’t cheap at $50 to $80/month.
I posted previously that satellite Internet access was “OK If You Have To”. Explained there why it suffers from high latency and is not good for either VoIP or gaming.
We’re still using it but it’s worse than I thought it’d be – especially when there’s bad weather around. It probably works much better far south of here where the antenna can really point up. But I’ve expanded my search for alternatives vastly. Will report as I (hopefully) find them.