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Japan to Deploy Massive Broadband Satellite
demachina writes "Japan has announced plans to deploy a massive broadband satellite operational in 2015. It will provide 100 Mbit/sec service to mountains, remote islands and bullet trains along with comm for disaster recovery. Its giant 66 ft. diameter dish is supposed to be able to receive even weak cell phones signals. Of course, the ping times wont be so good."
DirecWay (from DirecTV) offers satellite return service - no phone line necessary. I used it for about 6 months some time ago (when this area was total broadband hell, as opposed to only being partial broadband hell). It does work, but some major caveats:
But, if it's your only option, it's great. Seriously - in the same situation, I'd use it again
In LEO, one orbit takes about 90 minutes and gives ~9 minutes of coverage at any given point (numbers pulled from memory, so give or take 20%), so you'd need 10 satellites. Would that be worth it to eliminate the 0.2 s latency?
A geosynchronous satellite orbits at a height of approximately 38,500,000m. Light travels at a speed of approximately 300,000,000m/s. It therefore takes light approximately 250ms to make a round trip. This might be sub-optimal for gaming, but its about the ping time I remember from a modem. You might run into some problems with TCP rate limiting though - it's probably best to run some non-TCP protocol over the satellite link.
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Japan apparently has their own satellite launching infrastructure. Otherwise I think NASA and ESA both help with launching commercial satellites, it doesn't seem to be a big deal anymore.
The beam width is dependant on a lot of things. You can adjust the focus of the transmitter to turn the beam into a big fuzzy spot.
You would still have all the normal routing delays, so this would probably jack your ping time to slashdot up around 1000ms. It's the same sort of issue DirecWay systems have in that regard. That kind of latency is instant death if you're playing counterstrike or the like, of course, but for downloading email, web pages, even doing ftp or whatever it's still really not a big deal. It's probably enough to make VOIP annoying, but not unusable.
There are some alternatives with lower ping, but they all have problems. You could use an array of 10-12 low earth orbit satellites, for instance, so that you have have one in range at all times. I'm not sure how that would compare on expenses - the satellites would certainly be cheaper, as they wouldn't need the extra-powerful antennas, but probably the whole array would add up to be considerably more expensive. Launching costs would pose the same sort of pattern - cheaper launches perhaps, but probably not by a factor of 10-12. So it would be more expensive. You'd have much better latency, but you might also introduce a lot more complexity in targetting the moving objects with your signals.
In the end, it's probably not worth it. The intention here is clearly to give service to those in rural areas that don't have alternatives, and to provide emergency communication channels that are immune to terrestrial disasters, and this should do that admirably. Not being able to play counterstrike on it probably doesn't really affect it's core utility.
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Actually it's several islands and it's not that "compact". Its area is close to California and a tad larger than Germany. Unlike California though it does not have large forest/desert areas and unlike Germany it is more stretched (North to South). I don't think low-orbit satelites would work.
I think you'll need more sattelites than that. Remember that the earth spins inside their orbits so when the tenth satellite passes over Japan the first will be on the same latitude as Japan, but on a rather different longitude. Thus you'll need more satellites to cover Japan 24/7.
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Actually, it has been determined by one of the largest consumer data providers that satellite broadband is not economically viable. Hughes, the owner of DirecTV, had planned a massive rollout of this technology, due this year. After they had designed and (mostly) built the satellites, the numbers didn't look too rosy. Instead, they re-tasked the satellites for the new HD/MPEG4 DirecTV market. It is the classic case of a company spinning a failed product into a "fantasic innovation" (if you believe the new ads).
So, no, the US hasn't been left behind. The market forces have decided that there aren't enough dollars to support a venture and make lots of cash. This sucks for those in rural america, as the landline folks have also decided that you won't make them money. Our democracy and capitalism fails us in insideous ways. This is one example.
Is it just my observation, or are there way too many stupid people in the world?
A geostationary orbit is about 35,000km up. lets call that 50,000km as we might not be right underneath it. Light travels at 300,000km/s so the travel time for a message is ~166ms. multiply by 4 (a->sat, sat->b, b->sat, sat->a) gives ~666ms, the latency of the beast ;-).
OK, not the greatest but pinging slashdot gives me an average of 349ms from London,UK so it's not as good but then not terrible either.
There is one additional source of delay that you are failing to take into account. When encoding and decoding the bitstream into RF, there is some delay. The transmitting end has less than the receiving end. On the receiving end, the RF signal has to be digitized, run through some form of Fast Fourier Transform and decoded to get the bitstream. This will add some time to the pings.
On a different note, I'm currious as to how they are going to get 100mbit out there. On a 36Mhz ku band transponder, the maximum throughput is probably close to 200mbit using DVB-S2 (the latest and greatest satelite transmission codes). They are going to need a lot of transponders/bandwidth to provide satelite broadband to the boonies.
One thing on the ping times though. For regular downloading of webpages, What if they set up on the ISPs end a cache manager that would take your request for a web page, cache all content on that web page (and a few surrounding links) and then forward you the web page along with all associated images all at once so you weren't requesting everything a packet at a time?
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I suspect the term "dish" and any impression it is parabolic is an artifact of the reporting. I worked on a satellite system like this... It is geostationary and it has a gigantic antenna system composed of two umbrella-like devices. The "umbrella" was designed to create 140 "spotbeams" on the earth, for a total coverage of most of southeast Asia. Each spotbeam is the equivalent of a giant (300 Km diameter) cell in terrestrial networks. The system is called ACeS (Asia Cellular Satellite System) http://www.acesinternational.com/corporate/index.p hp?fuseaction=System.satellite
The re-tasking of the sats had less to do with broadband viability and MUCH MORE to do with Rupert Murdoch wanting to control DirecTV and make it competitive with other TV offerings like cable. At best you might say that NewsCorp/Murdoch didn't see broadband via sat. as viable but even that is pure supposition. By buying HNS, Murdoch got DTV and 2 satellite assets (including the orbit slots) that could be quickly converted to provide HD programming. From a business perspective this was a very smart move to give DTV a competitive offering now instead of in another couple years once they built their own satellites. Let me be clear though that to say Hughes gave up on broadband by satellite is an ignorant statement to make.
The current offering from Hughes, DIRECWAY, has over 250,000 broadband customers. They are getting new customers with home users as well as businesses (think chain stores with 1,000s of outlets, many of them out of reach of other broadband solutions). Our European division was recently signed to provide broadband for a leading credit company. All of this information is available at www.hns.com.
Also, the planned Spaceway offering, even with delays, will still be available well before this Japanese offering. Good luck to them getting all of the pieces together by 2015.
Obviously, I am being careful about what I say since I don't want to get in trouble with our corporate folks while trying to defend my company. The truth is that everything I know and see indicates a committment to satellite broadband by HNS.
This kind of a service is already available in the US http://www.infosat.com/services/hsi/index.html#