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Japan Launches "Super-Speed" Internet Satellite

kdawson posted more than 6 years ago | from the fiber-in-the-sky dept.

Space 159

A number of readers wrote in about the launch this morning of a Japanese H-2A rocket carrying a Kizuna ("Winds") satellite into orbit. Kizuna is intended to provide "super high-speed data transmission" for Japan and Southeast Asia. The news stories on the launch, such as the AP's linked here, are short on technical detail. For example they say the satellite successfully achieved orbit 175 miles above the earth — hardly suitable for Internet communications to a specific area on the surface (remember Teledesic?). Reader nebulus4 provided a link to the Japan Aerospace Exploration Agency site with an illustration and a little more detail. Such as the fact that Kizuna is destined for geosync orbit, and that a 45-cm antenna will equip eventual users for 155 Mbps down / 6 Mbps up, whereas a 5-m antenna will allow enterprises and ISPs to tap into 1.2 Gbps down. Given the latency to geosync orbit, you probably wouldn't want to use Kizuna to play an online shooter.

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159 comments

Remember Pearl Harbor!! (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#22529312)

Don't let them get nukes!!

Re:Remember Pearl Harbor!! (0, Offtopic)

palegray.net (1195047) | more than 6 years ago | (#22529404)

Remember Hiroshima [wikipedia.org] ; don't let anyone have nukes.

Re:Remember Pearl Harbor!! (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#22529568)

That's just my point. If they get nukes, we are going to be the first ones on the receiving end - those dudes want revenge!!!

Re:Remember Pearl Harbor!! (3, Interesting)

LingNoi (1066278) | more than 6 years ago | (#22529604)

I don't know what is worse..

The fact that you posted this racist crap in the first place or the fact that you posted anon so you could mod down anyone that responded to you.

Re:Remember Pearl Harbor!! (0, Offtopic)

Anonymous Coward | more than 6 years ago | (#22529878)

What's worse is that our resident genius couldn't even be bothered to post his reply [slashdot.org] to your comment in the right thread.
 
(By the way, the Japanese could easily nuke someone if they wanted to, but they're not stupid enough to start a nuclear war.)

Re:Remember Pearl Harbor!! (0, Offtopic)

Adambomb (118938) | more than 6 years ago | (#22529964)

Yeah, High population density + low land surface area is definitely not a position to start a nuclear war from heh.

Re:Remember Pearl Harbor!! (1)

ARRG.ch (1021385) | more than 6 years ago | (#22530662)

Whatever the country, the only winning move is not to play.

Re:Remember Pearl Harbor!! (1, Funny)

Adambomb (118938) | more than 6 years ago | (#22530724)

Unless you're pushing the button from your newly colonized extraterrestrial planet with a nice self-sustaining biosphere of its own =)

Re:Remember Pearl Harbor!! (1)

bigpicture (939772) | more than 6 years ago | (#22529992)

I didn't see what the original comment was, but I am guessing it was not about the technical merits of satellite internet. There is a difference between the intent and purpose of launching a communications satellite, and shooting one down. Maybe got he/she this confused.

Re:Remember Pearl Harbor!! (0, Offtopic)

TubeSteak (669689) | more than 6 years ago | (#22530786)

or the fact that you posted anon so you could mod down anyone that responded to you.
Next time you get mod points, log out, clear your cookies, and post anonymously.
Then log back in and try to use your mod points in that thread.
Anonymous isn't so anonymous.
Maybe it's just IP based, but it could easily be more complex than that.

In other news... (4, Funny)

Anonymous Coward | more than 6 years ago | (#22529322)

...the RIAA and MPAA today announced a plan to knock the satellite out of orbit with a missile to "protect the public".

Re:In other news... (4, Funny)

palegray.net (1195047) | more than 6 years ago | (#22529344)

They're not really trying to knock it out of space, they're just going to fire a cease and desist letter at it. Accidents do happen, though.

Re:In other news... (3, Insightful)

peragrin (659227) | more than 6 years ago | (#22529388)

how else does one get a cease and desist letter into orbit? On the tip of a missile, with the letter itself engraved upon a metal cylinder.

Re:In other news... (0)

Anonymous Coward | more than 6 years ago | (#22529588)

Ha! Thanks to Japan's 2006 mandate that all satellites must be able to transform into giant robots, the missile will simply be given a swift kick toward the RIAA and MPAA's secret underground bunker!
Chalk one up for the good guys!

Re:In other news... (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#22529766)

Correction - it isn't really racist. What does race have to do with it ? He just is worried about the Japanese nuking us as revenge. And hell, they did start the whole friggin thing.

Now featuring... (1, Insightful)

palegray.net (1195047) | more than 6 years ago | (#22529330)

Super Latency [isoc.org] !

Re:Now featuring... (3, Insightful)

Adambomb (118938) | more than 6 years ago | (#22529368)

Exactly, While this could be useful for bulk mobile file transfers, this definitely wont be used for anything real time.

I believe geosync orbit has a MINIMUM lightspeed latency of 119.4ms.

Not a fun starting point BEFORE collisions and noise.

Re:Now featuring... (2, Informative)

BSAtHome (455370) | more than 6 years ago | (#22529402)

Ehm, you also have to get back down, so that is 240ms minimum...

Re:Now featuring... (1)

Adambomb (118938) | more than 6 years ago | (#22529454)

wow, good call.

and another tally on the mind-is-dying meter.

=)

Re:Now featuring... (4, Insightful)

dgatwood (11270) | more than 6 years ago | (#22529800)

You have to multiply times four to get a useful figure. Latency is normally measured round trip. Hop up, hop down, return hop up, return hop down. Latency to geostationary orbit is half a second.

However, 175 miles up is NOT geostationary. Geostationary is 35,786 km up, give or take. The orbit is geosynchronous. That just means the orbital period is the same as the earth's rotation, so it returns to the same spot at the same time every day. It will NOT stay in the same place, however. They'll have to have several of these things in a similar orbit flying over periodically like we do for GPS satellites. It also means the round trip latency is about 3.76 msec (just less than a millisecond per hop), a heck of a lot shorter than half a second.

Re:Now featuring... (0)

Anonymous Coward | more than 6 years ago | (#22530010)

It will NOT stay in the same place, however.
Well, if it is positioned above the equator (which is the case for satellites which are referred to as geostationary), it does. If it does have the same rotation period as the earth it will just stay above its point above the equator.

Re:Now featuring... (4, Interesting)

absoluteflatness (913952) | more than 6 years ago | (#22530018)

Geosynchronous and geostationary orbits are obtained at the same radius from the Earth, about, as you say, 35,786 km above sea level. The defining factor that differentiates between geosynchronous and geostationary is the plane of the Earth the orbit is positioned over. A geosynchronous orbit that is directly aligned with the Equator is "geostationary" since it will always stay above the same position on the Earth. Plain "geosynchronous" orbits are simply aligned differently.

From the JAXA site about Kizuna:

"Scheduled orbit: Geostationary orbit at 143 degrees East longitude and at an altitude of about 36,000 km"

It is, even though the summarizer slipped up a bit (technically the term is correct, but somewhat misleading), destined for geostationary orbit.

Re:Now featuring... (1)

dgatwood (11270) | more than 6 years ago | (#22531332)

Ah. I wondered how you could possibly have an orbit as low as 175 miles. I would think you'd get horrible atmospheric drag, not to mention how fast it would have to be moving.... Apparently, the summary was massively wrong....

Re:Now featuring... (1)

Doug Neal (195160) | more than 6 years ago | (#22530904)

I've sometimes wondered how feasible it would be to have a combined very-high-speed satellite and "normal" speed ground-based net connection, whereby the traffic was duplicated over both links and recombined at each end. This would bring the latency down making it suitable for interactive traffic. Transfers would start slowly but then jump up to high speed as the satellite link kicks in. The router could then signal to the other end that it could stop transferring over the ground-based link.

I can't think of a way of doing this without having huge buffers in the routers though. I haven't heard about this being done anywhere, I'd imagine cost and complexity of router hardware and software is the main reason why.

Re:Now featuring... (1)

Karrots (14012) | more than 6 years ago | (#22529488)

Back to the modem days.

Re:Now featuring... (1)

Cecil (37810) | more than 6 years ago | (#22529506)

And assuming you're talking about a round trip, which "latency" generally does, that doubles again to 480ms. Which is about the typical minimum ping time for your run-of-the-mill satellite internet these days. Switching delays are fairly negligible on that sort of a timescale, even with huge numbers of connections provided you're using fairly modern technology. Look at the cellphone networks: this is a solved problem.

Re:Now featuring... (1)

milsoRgen (1016505) | more than 6 years ago | (#22529586)

Ehm, you also have to get back down, so that is 240ms minimum...
Still couldn't this provide some measure of redundancy in cases where the hard lines are damaged or taking down for whatever reason, like we recently saw in the middle east?

Re:Now featuring... (1)

cheater512 (783349) | more than 6 years ago | (#22529808)

Australia has 250ms lag to the US minimum.
I'd sure prefer their speeds over 512k though. ;)

Re:Now featuring... (1)

jamstar7 (694492) | more than 6 years ago | (#22530376)

Bulk mobile one way, say, to an offsite backup server farm. That 155 Mbps looks awful tasty on the download link. Should be able to move lottsa pr0n...

The 5 Mbps uplink is kinda weak, though. Forget about bittorrent...

Re:Now featuring... (1)

b1t r0t (216468) | more than 6 years ago | (#22530988)

Here is the result of a ping session over a satellite link. It was done at a rest area along IH-35 in Texas:

$ ping xxxxxx.net
PING xxxxxx.net (xx.xx.xx.xx): 56 data bytes
64 bytes from xx.xx.xx.xx: icmp_seq=0 ttl=50 time=1177.625 ms
64 bytes from xx.xx.xx.xx: icmp_seq=1 ttl=50 time=837.073 ms
64 bytes from xx.xx.xx.xx: icmp_seq=2 ttl=50 time=848.406 ms
64 bytes from xx.xx.xx.xx: icmp_seq=3 ttl=50 time=1072.072 ms
64 bytes from xx.xx.xx.xx: icmp_seq=4 ttl=50 time=1079.655 ms
64 bytes from xx.xx.xx.xx: icmp_seq=5 ttl=50 time=874.343 ms
64 bytes from xx.xx.xx.xx: icmp_seq=6 ttl=50 time=965.390 ms
64 bytes from xx.xx.xx.xx: icmp_seq=7 ttl=50 time=1081.254 ms
64 bytes from xx.xx.xx.xx: icmp_seq=8 ttl=50 time=844.191 ms
64 bytes from xx.xx.xx.xx: icmp_seq=9 ttl=50 time=903.456 ms
^C
--- xxxxxx.net ping statistics ---
11 packets transmitted, 10 packets received, 9% packet loss
round-trip min/avg/max/stddev = 837.073/968.346/1177.625/118.230 ms

I'm sure they'll be using TCP ACK spoofing in the ground satellite transceiver boxes.

Re:Now featuring... (1)

vertinox (846076) | more than 6 years ago | (#22529916)

Super Latency

I dunno. If I had the choice between no internet or satellite, I wouldn't complain about the latency.

Of course it might suck if it rains a lot, but I suppose it is far better than not having any internet. Secondly, if you are a SE Asia islander or boat traveler you might not even have dial up seeing there is no fiber to your location. You might have a LAN line, but it might be incompatible or really slow seeing regular modems don't work well with satellite phones.

Re:Now featuring... (1)

drinkypoo (153816) | more than 6 years ago | (#22530564)

I can get dialup or satellite. I can't play a game over the dialup anyway. I usually get 26.4kbps. Good times. I'm planning to get Hughesnet, which is the ONLY one that will give you a decent transfer allotment. Or so they say. Everyone else cuts you off pretty low.

Version 1 is just Super..wait for v2 (0)

Anonymous Coward | more than 6 years ago | (#22529334)

I'm not going to waste my time with this version 1 "Super" speed
version 2 is going to give me "Hyper Mega" Speed and that's when *I* will jump on the bandwagon.

Re:Version 1 is just Super..wait for v2 (1)

palegray.net (1195047) | more than 6 years ago | (#22529366)

I'm going to wait until it's Super Saiyan [wikipedia.org] .

Re:Version 1 is just Super..wait for v2 (1)

Cheerio Boy (82178) | more than 6 years ago | (#22531020)

I'm going to wait until it's Super Saiyan [wikipedia.org] .
Its transfer rate is over TEN THOUSAND!

;-P

Sorry - couldn't resist. I'll get my hat...

Using Kizuna to play an online shooter... (0)

Anonymous Coward | more than 6 years ago | (#22529354)

...would be a kamikaze mission.

You cannot be serious (3, Insightful)

Zorbo88 (1240952) | more than 6 years ago | (#22529390)

So a subsistence farmer in rural Indonesia gets a better download speed than me, a sophisticated suburban Australian. Awesome.

Re:You cannot be serious (0, Flamebait)

Dunbal (464142) | more than 6 years ago | (#22529462)

So a subsistence farmer in rural Indonesia gets a better download speed than me, a sophisticated suburban Australian. Awesome.

      Don't worry the kiwi's have apparently come up with a sheep powered device that's even faster. Coming to Australia soon.

Re:You cannot be serious (2, Informative)

daBass (56811) | more than 6 years ago | (#22530636)

You laugh about the Kiwis, but we get virtually all our internet here in Oz via the Souther Cross Cable [wikipedia.org] system. A system with NO australian ownership whatsoever. The majority owner? Telecom New Zealand, with a 50% stake.

Yup, if it weren't for the Kiwis we'd still be sending our email by morse code. (The next biggest cable, between Australia and Japan isn't anywhere near big enough and came online several years after the SCC)

Gotta hand it to them; they wanted a big cable for themselves but probably couldn't make it profitable - so they extended it over here and not only are they taking our money via their virtual monopoly, we gladly allow them to do so because no Australian telecom could be f***ed in late 1990s to get us seriously hooked up.

Re:You cannot be serious (3, Insightful)

pembo13 (770295) | more than 6 years ago | (#22529784)

Well nothing really makes you better than him to begin with, so you're not generally entitled to better internet than him.

Re:You cannot be serious (1)

rastoboy29 (807168) | more than 6 years ago | (#22531502)

Dude, he's not saying he's better, he's saying that his country has set things up so that this is the case, and it is a travesty since he lives in a first world  country.

Get that chip off your shoulder before your hurt yourself.

Re:You cannot be serious (1, Insightful)

Kjella (173770) | more than 6 years ago | (#22529860)

If he could pay for it, it's sorta like the T3 you can't buy because you don't have the cash either. At any rate, I'll wait to see how much they really get out of this, I've had a friend with satellite service that's way in the outbacks and it was expensive, unstable, underdelivered on bandwidth and latency was higher than advertisied and it was in general a pain to use. He jumped to cable first chance he got, I don't remember which but it was one of those bloody-sucking underdelivering monopolies that get mentioned on slashdot and he was much happier all the same. Now, if this can really deliver I don't see why they can't launch a few over the US and Europe and whereever else might need high-speed Internet. 155/6 Mbps would beat anything I can find around here on downstream, even the fastest fiber connection I've seen offered is 50/25 Mbps. Which would be nice too, if I could get that and not the 2/0.4 Mbps connection I do have...

Re:You cannot be serious (0)

Anonymous Coward | more than 6 years ago | (#22531236)

Probably comcast.
I was bored yesterday and googled "Damn Comcast" in quotes, and i got over two thousand pages containing those exact words. Who knows how many would have come up if I had used more a derogatory phrase.

Re:You cannot be serious (1)

misleb (129952) | more than 6 years ago | (#22530238)

So a subsistence farmer in rural Indonesia gets a better download speed than me, a sophisticated suburban Australian. Awesome.


Have you ever tried using satellite internet before? You'll soon realize that speed isn't everything.

-matthew

Re:You cannot be serious (1)

AHuxley (892839) | more than 6 years ago | (#22530358)

Wait for the url filter to kick in.
Then you will have subsistence internet too.

Re:You cannot be serious (1)

Fear the Clam (230933) | more than 6 years ago | (#22531064)

So a subsistence farmer in rural Indonesia gets a better download speed than me, a sophisticated suburban Australian. Awesome.

Payback for Yahoo Serious is a bitch.

Geosynchronous Latency (4, Insightful)

dsginter (104154) | more than 6 years ago | (#22529400)

22,233 miles to the satellite
round trip = times 4 = 88,932 miles

speed of light (wave propagation) = 186,282 mi/sec

latency = 88,932 / 186,282 = 0.477 seconds (on top of regular network latency)

Curse you speed of light. You win again!

Re:Geosynchronous Latency (1)

BSAtHome (455370) | more than 6 years ago | (#22529424)

That just means that you need to have a large TCP window to compensate the large bandwidth-delay product. No real problem. The connection sucks for anything interactive, but bulk is just fine.

Re:Geosynchronous Latency (5, Funny)

Dunbal (464142) | more than 6 years ago | (#22529448)

The connection sucks for anything interactive

      Except, possibly chess.

Re:Geosynchronous Latency (0, Offtopic)

geonik (1003109) | more than 6 years ago | (#22529694)

Except, possibly chess.

And Quake too! The Quake engine interpolates your movements when your packets arrive too late for other players.

I am so bad at this game, that I usually live much longer when my latency is over 1500ms.

Re:Geosynchronous Latency (2, Interesting)

SashaM (520334) | more than 6 years ago | (#22530794)

The connection sucks for anything interactive

Except, possibly chess.

I know you were joking, but as an administrator on a chess server, I can tell you that people get pretty pissed off when lagging half a second. It's acceptable for playing long games, but most over-the-net chess games are 1 to 5 minutes per player per game. Yes, it's a whole different game that just shares moving rules with "chess".

Re:Geosynchronous Latency (1)

drspliff (652992) | more than 6 years ago | (#22531136)

We have a number of customers using VoIP over satellite connections, it takes a few seconds to get used to it for both people on the call but after that it's hardly noticable.

Re:Geosynchronous Latency (2, Informative)

Pros_n_Cons (535669) | more than 6 years ago | (#22529514)

That just means that you need to have a large TCP window to compensate the large bandwidth-delay product. No real problem. The connection sucks for anything interactive, but bulk is just fine.
I've got satellite. Latency effects more than you think. Yes for big files its fine but p2p, web surfing, voip, if you voice chat. Sometimes my latency is 2-3000ms. id rather have a 384kb dsl line at home and just grab my .iso's at work.

Re:Geosynchronous Latency (1)

Bert64 (520050) | more than 6 years ago | (#22529558)

Depending on the cost and throughput, i would consider getting satellite in addition to my DSL for bulk transfers...
Use bittorrent to download to a fast server, and them download it over the satellite link from there.

Re:Geosynchronous Latency (0)

Anonymous Coward | more than 6 years ago | (#22530980)

You'd really not even need BT to download to a fast server: Your BT speeds, on the whole, will be unaffected by the satellite lag. BT expects packets to be slow in coming. It doesn't care.

Re:Geosynchronous Latency (1)

JonWan (456212) | more than 6 years ago | (#22529478)

Why not put up a bunch of them up (like GPS) and just hop around to available Sats as they come over the horizon ?

  Note:
I know nothing at all about this stuff, so be nice when you call me a idiot.

Re:Geosynchronous Latency (1)

kcbanner (929309) | more than 6 years ago | (#22529492)

Because, then you have X "wasted" satellites in orbit...only one is being used at a given time. Its silly not to make it geosync.

Re:Geosynchronous Latency (2, Interesting)

Atlantis-Rising (857278) | more than 6 years ago | (#22529600)

Unless of course you sell service to people all over the globe with a constellation of LEO satellites.

  In any case, a Molniya orbit would only require three satellites for coverage, looks ideal for Japan as a nation, and the perigee can be as low as ~400km. The round-trip latency for 400 km would be (400*4/300,000), or 5ms (if my mental mathematics is not off by a decimal point or so).

Yes, you'd need three satellites, admittedly.

Molniya orbits (2, Insightful)

mangu (126918) | more than 6 years ago | (#22529686)

a Molniya orbit would only require three satellites for coverage ... The round-trip latency for 400 km would be (400*4/300,000)

Problem is, a Molniya orbit requires three satellites for coverage at the apogee, which is at about the same altitude as the geosynchronous orbit. At the perigee the satellites move faster, so you need more of them to keep one always on sight.

Re:Geosynchronous Latency (1)

jamstar7 (694492) | more than 6 years ago | (#22530410)

Not to mention that your dish has to 'track' the satellite to get a decent connection time. Then it has to swing back to the 'start' position to pick up the next satellite in orbit.

Re:Geosynchronous Latency (1)

tylernt (581794) | more than 6 years ago | (#22531050)

Not to mention that your dish has to 'track' the satellite to get a decent connection time. Then it has to swing back to the 'start' position to pick up the next satellite in orbit.
Don't use a dish, use something like a collinear array that has it's gain spread along a thin line (the path of the satellite as seen from earth). You'll need a reflector of course. You only have to aim it once (if the satellite is passing nearly overhead -- won't work as well if the sat is describing an arc nearer to the horizon, though).

Re:Geosynchronous Latency (1)

frieko (855745) | more than 6 years ago | (#22529890)

Well, since data rate is proportional to SNR you need a dish to accomplish any sort of decent speeds. Which would mean having to track the sat in real time. Armchair astronomers out there - would it be feasable to make a satellite-tracking consumer product?

Re:Geosynchronous Latency (1)

Orange Crush (934731) | more than 6 years ago | (#22530614)

Yes [gosatellite.com] . But it's a bit pricey.

Re:Geosynchronous Latency (0)

Anonymous Coward | more than 6 years ago | (#22529704)

For example they say the satellite successfully achieved orbit 175 miles above the earth

175 < 22,233

That makes for 3.76ms latency for those directly below it.

Re:Geosynchronous Latency (1)

Dare nMc (468959) | more than 6 years ago | (#22529842)

round trip = times 4 = 88,932 miles

what, you don't think it would be appropriate to put your servers in geosynch orbit as well?

Re:Geosynchronous Latency (1)

cjb658 (1235986) | more than 6 years ago | (#22530264)

22,233 miles to the satellite

Is there a reason the satellite has to be up this high? Could it be at a lower altitude?

Re:Geosynchronous Latency (1)

jamstar7 (694492) | more than 6 years ago | (#22530454)

Is there a reason the satellite has to be up this high? Could it be at a lower altitude?

Not if the satellite is going to appear to sit in one spot in the sky. At geosynch altitude, the sat has an orbit of 24 hours, thus, appears to be stationary.

Re:Geosynchronous Latency (1)

Ambiguous Puzuma (1134017) | more than 6 years ago | (#22530872)

It could not be at any other altitude without some kind of continuous propulsion (or other force besides gravity acting on it).

If I remember right (it's been a while since I've studied any physics) a simplified explanation looks something like this:
(1) a = v^2 / r [equation for centripetal acceleration]. For an object to maintain a constant speed in a circular path, it must accelerate at a rate of v^2 / r perpendicular to the direction of motion, where v = velocity and r = radius of circle.
(2) a = m_Earth G / r^2 [equation for gravitational acceleration]. The acceleration must be due to the Earth's gravity alone, so we use the equation for acceleration due to gravity. m_Earth is a constant (the mass of the earth); G is the gravitational constant.
(3) v = 2 pi r / t_rotation. For the orbit to be geosynchronous, it must take the same length of time to complete one orbit as it takes the Earth to complete one rotation (t_rotation).
(4) r = r_altitude + r_Earth. The center of the earth is the center of the satellite's orbit; the radius of the circle is the altitude of the satellite (distance from satellite to surface of the Earth) plus the radius of the Earth at the equator (distance from the surface of the Earth to the center). It must be at the equator because the direction of motion of the satellite must be the same as the direction of the Earth's surface below the satellite.

Solving these equations simultaneously for r_altitude, you get:
r_altitude = (m_Earth G t_rotation^2 / 4 pi^2)^(1/3) - r_Earth

Plug in approximate values for the constants:
m_Earth = 5.97 * 10^24 [kg]
G = 6.67 * 10^(-11) [m^3 / (kg s^2)]
t_rotation = 86400 [s]
pi = 3.14
r_Earth = 6.38 * 10^6 [m]

And you get 3.59*10^7 meters, or 22,300 miles. You can substitute in the mass, time of rotation, and radius of any other planet/moon/etc. to find the altitude of a geostationary orbit around something other than Earth.

Re:Geosynchronous Latency (1)

drinkypoo (153816) | more than 6 years ago | (#22530598)

From what I've read latency over 1 second is typical. It makes sense; the data is probably spread out and repeated so that the lost parts of the signal can be pieced back together. I mean, phone modems encode data like this these days too...

This just goes to show (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#22529538)

Countries that don't have niggers in the population develop the best technology.

Re:This just goes to show (0, Flamebait)

maGiC_RS (946022) | more than 6 years ago | (#22529910)

yeah, it's fucking retarded that even gooks are beating us Whites due to the nigger infestation now

Re:This just goes to show (0)

Anonymous Coward | more than 6 years ago | (#22530424)

You DISGUSTING RACIST TROLL!

Re:This just goes to show (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22530566)

Quit spamming slashdot with this crap. I thought the GNAA was long dead.

Am I the only one... (1)

wertigon (1204486) | more than 6 years ago | (#22529712)

Who for a brief moment thought "Wait, they've developed a satellite with internet access that orbits the earth at insanely high speeds?" or something similar? Sleep-depraved mind FTW. :p

175 miles (4, Informative)

heroine (1220) | more than 6 years ago | (#22529932)

175 miles is the separation altitude for the rocket. Satellites usually boost themselves to geostationary orbit. The Delta IV heavy can blast all the way to geostationary orbit but no-one can afford it.

As a satellite dish internet installer & user. (1)

Brad1138 (590148) | more than 6 years ago | (#22529972)

IT SUCKS!!! I install WildBlue, 1 of the 2 main Sat. ISP's. It doesn't matter how fast the connection speed is, the latency SUCKs. It averages 1200-1800 ms (no that's not a typo, check it out if you want). You can not play online games, outside of backgammon. The only thing I can say for it is, it is better than dial-up, although you can play some online games w/dial-up.

Re:As a satellite dish internet installer & us (1)

TooMuchToDo (882796) | more than 6 years ago | (#22530028)

With regards to latency, it's pretty hard to make light go faster, well, then light. Damn you physics!

PULL (1)

lazy genes (741633) | more than 6 years ago | (#22530002)

Just like shooting skeet.

Latency? What latency? (0, Redundant)

kentrel (526003) | more than 6 years ago | (#22530068)

This might seem like a stupid question, but why would there be latency with a satellite link? With radio waves traveling at the speed of light what difference is 175 miles going to make?

I always thought the reason for latency was a combination of signals going through slower copper wires and being processed by various routers and servers along the way.

Can someone clear this up?

Re:Latency? What latency? (4, Insightful)

Dunbal (464142) | more than 6 years ago | (#22530178)

With radio waves traveling at the speed of light what difference is 175 miles going to make?

175 miles? Try more like 22,230 miles. That's pretty much the only place you can put it unless you want your internet connection to only work 3 minutes out of every 90 minutes...

The reasons are simple physics. Gravity causes everything to want to fall towards the center of the Earth. Satellites manage to stay in orbit because they are constantly "falling" ahead of the Earth. That's why things in "low earth orbit" are referred to as being "in freefall" and not REALLY in zero gravity. Gravity is still there, only the velocity of the satellite is so high that all gravity manages to do is curve the trajectory of the satellite, not cause it to lose height. This means your satellite is going to be moving VERY fast with respect to the ground.

It's only at 22,230 miles out where the circle is so big that your satellite now appears fixed with respect to the ground. It's still moving. It's still "free-falling". But it appears to be hovering over a fixed spot over the equator - very useful for communication satellites since now you know where to aim your antenna and you don't have to bother moving it.

Re:Latency? What latency? (0)

Anonymous Coward | more than 6 years ago | (#22530968)

From the article:

The satellite, equipped with two large multi-beam antennas, separated from the rocket and successfully entered its intended orbit 175 miles from Earth, JAXA said in a statement.
I hope that's right. I'm so ready for fast satellite, weather balloon, stratellite or similar internet communications.

But... (1)

kitsunewarlock (971818) | more than 6 years ago | (#22530084)

Did they paint it red so it'll go 3 times faster than a normal Satellite connection?

Re:But... (1)

Cheerio Boy (82178) | more than 6 years ago | (#22531122)

Did they paint it red so it'll go 3 times faster than a normal Satellite connection?
Of course not! Don't be silly!

All good satellite people use a trusted brand of Satellite Wax!

6Mbps uplink (1)

Horizon_99 (58767) | more than 6 years ago | (#22530120)

Any Idea how the uplink is supposed to work? Can thousands of 45cm dish all communicate with the satellite at 36,000km simultaneously? I know that years ago you needed a DSL/Dial-up connection for the uplink, is the not the case anymore?

Re:6Mbps uplink (1)

DarthBart (640519) | more than 6 years ago | (#22531318)

Probably the same TDM multiplexing that Hughesnet and the other 2-way providers use. Each customer transmits in a burst in sequence. Each satellite has several TDM channels and each channel will support X number of customers.

Now what we need (1, Funny)

fishthegeek (943099) | more than 6 years ago | (#22530154)

is something to solve the last "175 mile problem." Okay. What if we replace all of that empty space with something that we'll call "FIBER". Only instead of running all of the fiber to the satellite and back we could just run it over land. Barring any service interruptions by 30 story lizards breathing fire all over the data center this might just work!

Fantastic ! (1)

ultranova (717540) | more than 6 years ago | (#22530278)

This means that new series are available to fansubbers even sooner than previously ! Yarrrr !

What happens when (not if) ... (3, Insightful)

Art Pollard (632734) | more than 6 years ago | (#22530296)

With all this reliance on satellite technology for GPS, communications, and weather prediction what happens when (not if) the sun hits a more active solar cycle eliminating all of these satellites in one fell swoop? We have become terribly dependent on satellite technology (that I agree is cool). However, there have been solar storms that would knock out all of our satellites in recent memory -- only we did not have any satellites up yet. Now the satellites are up and the next large solar storm is just lurking out there getting ready to strike.

As usual, beware any significant reliance on any one technology.

Latency (1)

aflag (941367) | more than 6 years ago | (#22530366)

From my calculations the latency to go up to the satellite and come back would be about 1ms. I don't think that's bad latency at all. Am I missing something here? What I did: 281,635.2m / 299,792,458m/s = 0.00093s

Re:Latency (1)

NatasRevol (731260) | more than 6 years ago | (#22530774)

You're missing a few decimal places... The distance is 35,000 kilometers times 4 for a round trip of latency. 140,000,000/300,000,000 = ~0.5 sec

Here is the solution for ISPs (0)

Anonymous Coward | more than 6 years ago | (#22530372)

ISPs complain about having videos delivered through their networks, or that upgrading their networks (fiber) to support video delivery would be too expensive. Here is the solution ! Put a satellite in orbit above US for massive data delivery (big (sec) latency is not an issue when starting to watch an HD movie), and keep the old "pipe" network for web apps, games (low (msec) latency).

Actually, I think that US gov should put such satellite in orbit and rent it to ISPs, but that the socialist in me talking :)
This country needs true high-speed internet to compete with the rest of the world. How ironical it is, that a big part of the web innovation comes from the US, but most of us can not even access it (online gaming, VoIP, IPTV, etc.) ? Hopefully, the next president will understand the advantage to have a high-speed internet available in the country.

Broadband Penetration (1)

allscan (1030606) | more than 6 years ago | (#22530436)

This should help with broadband penetration. I know, you'll never be able to use it for gaming. However, when the US isn't on a top ten list of connected countries, its really sad. Something like this could help those in very rural areas get connected.

Re:Broadband Penetration (1)

YrWrstNtmr (564987) | more than 6 years ago | (#22531028)

However, when the US isn't on a top ten list of connected countries, its really sad.

No, it's not. We were the first connected country. That others have leapfrogged with new technology is to be expected.

If we were to adopt whatever is absolutely fastest today...and somehow roll it out to every house and business in the next 60 days...infrastructure, last mile, everything...by the end of the year, some other country would be 'more connected'.

Every year, some new, faster tech comes out. You want to rewire the entire country every year or so? Not gonna happen.

Re:Broadband Penetration (1)

JordanL (886154) | more than 6 years ago | (#22531292)

Every year, some new, faster tech comes out. You want to rewire the entire country every year or so? Not gonna happen.
Do they seriously come up with a completely new type of fiber every single year? Or were you extending what you know about Dell computers to network topography?

Kizuna = "Bonds" not "Winds" (5, Informative)

jmf (30234) | more than 6 years ago | (#22530444)

The name of the satellite has been mistranslated: 'kizuna' () means bonds [msmobiles.com] (as in 'family bonds') and not 'winds', which makes a lot more sense given the satellite's function.

Re:Kizuna = "Bonds" not "Winds" (3, Informative)

tkh (126785) | more than 6 years ago | (#22530776)

I had thought the same thing, but that's not correct. If you look at the JAXA page on the nickname [www.jaxa.jp] , Kizuna is the nickname and the official name is WINDS (spelled all uppercase) which is an acronym. It's very confusing though.

Hmmm... Latency... (voice of Homer Simpson) (0)

Anonymous Coward | more than 6 years ago | (#22531278)

Geo-stationary sattelite + (Information) Teleportation = 0 Latency

At least (1)

okinawa_hdr (1062664) | more than 6 years ago | (#22531392)

It's up there now...until the United States decides to shoot it down.

total system capacity of course is not mentioned (0)

Anonymous Coward | more than 6 years ago | (#22531504)

Any satellite is power limited due to Shannon's law. That a 2.7 ton satellite in space can generate one (1) link at 1.2GBps to a dish 15 feet accross is the reality.
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