×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

First modernized GPS satellite Launched

Hemos posted more than 8 years ago | from the keeping-up-with-the-neighbors dept.

Space 221

keen writes "The first GPS 2R-M satellite has launched from Cape Canaveral, Florida on top of a Boeing Delta 2 rocket. The government is now competing with Europe's Galileo system, and has added two additional military channels and one civilian channel, which will increase the accuracy and performance of GPS - as well as increase its resistance to jamming."

cancel ×
This is a preview of your comment

No Comment Title Entered

Anonymous Coward 1 minute ago

No Comment Entered

221 comments

You Will Be Assimilated! (5, Interesting)

AKAImBatman (238306) | more than 8 years ago | (#13650461)

You know, I was about to ask the rocket scientists hanging around here (hi guys!) about how small new generation comsats were going to be. After all, there has been a tremendous increase in miniturization and technology since the original GPS sats were launched. (e.g. better microprocessors, denser batteries, more efficient solar panels, better propulsion, etc.) If we could get these sats small enough, it might be possible to deploy a GPS system for Mars in one or two launches.

Then I saw the borg cube that assimilated the Willy Wonka Chocolate Factory [lockheedmartin.com] (Mirror [nyud.net]) Excuse me while I pick my jaw up off the floor.

On another note, the picture makes it look like the design hasn't changed much from the original NAVSTAR [wikipedia.org] configuration. I assume that these satellites are merely sharing the same chassis, and have very different internals?

Re:You Will Be Assimilated! (2, Interesting)

madaxe42 (690151) | more than 8 years ago | (#13650551)

You find a way of fitting a Caesium fountain clock in a smaller case.

Look everyone! Somone who didn't RTFA! (1)

tgd (2822) | more than 8 years ago | (#13650563)

;-)

Seriously, they talk about that in the article. Its a little bit of modernized hardware in essentially the identical satellite.

Re:Look everyone! Somone who didn't RTFA! (3, Interesting)

AKAImBatman (238306) | more than 8 years ago | (#13650627)

Yeah, I did read it. The part that stuck out to me was that the new sats were about 60 pounds heavier than the old ones. Now I understand that they couldn't have gotten all the new features in for only 60 pounds without modern technology. Still, I can't help but think that it could have been a lot smaller than that.

Then again, I'd like to see a day when we can create useful PongSats [parallax.com], for this stuff but I supposed that won't be happening anytime soon. (Especially not when you need a large tranceiver!)

Re:Look everyone! Somone who didn't RTFA! (5, Insightful)

cerberus4696 (765520) | more than 8 years ago | (#13650752)

You have to remember that they're overengineering these things by terrestrial standards, because the satellites have to withstand some fairly harsh conditions while in orbit (such as radiation, EM storms from solar flares, etc). I imagine they're also hardened to some degree against human-generated interference, given all the worrying the Air Force has been doing lately about space warfare. Given all that, I'm not surprised that they seem excessivly bulky by the standards of present technology.

Re:Look everyone! Somone who didn't RTFA! (4, Insightful)

GileadGreene (539584) | more than 8 years ago | (#13650901)

The thing is making a satellite slightly lighter doesn't buy you much. You need a substantial drop in mass in order to get down to a cheaper launch vehicle. So given that you're already constrained to launch on a particular LV, why not pack in as much capability as possible? The Air Force in particular has a habot of keeping upgraded satellite designs at the same (or similar) mass as their predecessors, but adding lots of extra functionality.

The other thing to keep in mind is that there are many things that contribute to the total spacecraft mass in addition to the electronics. Not all of them have undergone the same kind of Moore's law reductions in mass (or improvements in capability) that electronics have.

Re:You Will Be Assimilated! (1, Funny)

Anonymous Coward | more than 8 years ago | (#13650569)

Looks like the just cable-tied 4 racks together, wrapped them in shiny copperfoil and added some barberpoles on top for extra oomph. Off it goes !

Re:You Will Be Assimilated! (4, Informative)

jurt1235 (834677) | more than 8 years ago | (#13650598)

Depending on the rocket which launches the satellite, there will be a general base for the satellite to be build on. You need to be able to mount the satellite on the rocket. Total reuse of the framedesign will save a significant amount of money, so there will be attempts to reuse the frame, solar panels, and general control systems. This ofcourse if the power signature of the new equipment matches with what the frame can deliver.

One thing is a bit weird though about the first photo. Usually these satellites are assembled in clean rooms with people wearing all kinds of protection against static electricity build up and anti dust covers. So I wonder if the satellite in this picture is just a mockup to make a testfit of the equipment (never trust the drawings).

Re:You Will Be Assimilated! (1)

dwater (72834) | more than 8 years ago | (#13650739)

> So I wonder if the satellite in this picture is just a mockup to make a testfit of the equipment (never trust the drawings).

Perhaps they were worried they'd mix up imperial with metric again. My memory is fading - is this [wikipedia.org] the only notable time?

Re:You Will Be Assimilated! (2, Insightful)

cpu_fusion (705735) | more than 8 years ago | (#13650918)

So I wonder if the satellite in this picture is just a mockup to make a testfit of the equipment (never trust the drawings).

Given the military nature of the project, perhaps it is just a "PR model" for secrecy.

Re:You Will Be Assimilated! (3, Interesting)

pr0nbot (313417) | more than 8 years ago | (#13650608)

If we could get these sats small enough, it might be possible to deploy a GPS system for Mars in one or two launches.

OT... something I've been wondering about, with regard to long-range communication with satellites: we know how to do networks now, why aren't we peppering space with small node probes that travel away from Earth (i.e. aren't orbital satellites) but keep in touch with eachother and so can route the data from real science probes back to us from further and further out?

I suppose the number of nodes required would grow at the same order as the volume of a sphere (assuming we want to spray them in all directions) but we actually probably only want to send them out in specific directions.

Re:You Will Be Assimilated! (4, Informative)

AKAImBatman (238306) | more than 8 years ago | (#13650658)

OT... something I've been wondering about, with regard to long-range communication with satellites: we know how to do networks now, why aren't we peppering space with small node probes that travel away from Earth

1. Nanoprobes wouldn't have a large enough transceiver dish.
2. We are. Have you heard of the NASA Deep Space Network [wikipedia.org]? Every sat and probe we launch becomes part of NASA's network in space. That's why when they had communications problems with the Mars Rover, they were able to send reset commands from a probe heading elsewhere. As long as they can find a number of sats with the necessary line of sight, NASA can communicate with any probe, anywhere. Even if it's on the other side of the Sun. :-)

(No, I am not privy to the exact locations of anything. So take this with a grain of salt. We have a lot of hardware up there, but space is a big place.)

Re:You Will Be Assimilated! (1)

jacksonj04 (800021) | more than 8 years ago | (#13650790)

Go go gadget mesh networking.

Perhaps what we need to augment this system is a cloud of smaller satellites in orbit armed with short to mid-range tracking so that they can pick out space debris. When something is found which happens to be in the path of something else, it can flag up with mission control so that (if the colliding objects are easily moveable) the offending items can be shunted out of the path temporarily.

Alternatively, satellites which realise something is wrong with themselves can send out a general "I'm screwed" message without needing to wait for LoS to a ground transmitter.

Re:You Will Be Assimilated! (4, Informative)

ChrisA90278 (905188) | more than 8 years ago | (#13651175)

You've been reading to much science fiction. Yes there are some cases where spacecraft use inderect means of communication through a relay but this is not done ad-hoc using some general purpose capability built into every spacecraft. In every case wherwe relay is used the capabilty is plaanned from the beginning. The idea of selecting some random spacecraft to use as a relay to soe other random spacecraft just can't work. The orbiters currently on mars were design specifically to relay. Closer to Earth TDRSS acts as a relay between low Earth orbit and the ground. Notice (1) that TDRSS is the relay, thaey are NOT sending data between randon spacecraft and (2) the data are passed only between LEO and the ground, not through out the solar system or even to geosync. orbit. http://msp.gsfc.nasa.gov/tdrss/oview.html [nasa.gov]

Re:You Will Be Assimilated! (1)

Xaositecte (897197) | more than 8 years ago | (#13651424)

Ehh, not so much. All you really need to make a relay is a few capabilities:

1. Antennas, Preferably ones you can point in the direction you want. Not so hard in space given the (usually) low loss of sending signals through space, and the wide dispersal. Built into every Satellite

2. Transmit\Recieve: Again, assuming you can contact it, and it can contact you, also built into every Satellite.

3. The ability to change transmit\recieve frequencies: Might not have been included on some of the older or more specialized Satellites, but certainly possible these days.

Far from being impossible, assuming a little forethought on NASA's part, it's probably true.

Re:You Will Be Assimilated! (2, Informative)

LandKurt (901298) | more than 8 years ago | (#13651377)

Have you heard of the NASA Deep Space Network? Every sat and probe we launch becomes part of NASA's network in space. That's why when they had communications problems with the Mars Rover, they were able to send reset commands from a probe heading elsewhere.

Did you even read the Wikipedia article you linked to? The Deep Space Network is an earth based network of large radio dishes that listen to deep space probes. It's not located in deep space. It's almost always easier to talk to a distant probe with a huge dish on earth than to try and use the small dish on another probe.

The closest thing to what you're discussing is NASA's TDRS system. That relays signals from earth orbiting satellites to the ground.

Re:You Will Be Assimilated! (1)

Verteiron (224042) | more than 8 years ago | (#13650755)

Completely off-topic, but your description (borg cube that assimilated the Willy Wonka Chocolate Factory) cracked me up even before I saw the picture. Having seen the picture, I can say that your description is not only amusing but 100% accurate. Kudos.

Re:You Will Be Assimilated! (-1, Flamebait)

thogard (43403) | more than 8 years ago | (#13650824)

Why is this rated +5? is there a now +5 clueless?
Where the heck are the editors?

Re:You Will Be Assimilated! (2, Interesting)

GileadGreene (539584) | more than 8 years ago | (#13650843)

On another note, the picture makes it look like the design hasn't changed much from the original NAVSTAR configuration. I assume that these satellites are merely sharing the same chassis, and have very different internals?

No, they're substantially different designs. Different manufacturers even (Rockwell vs Lockheed). But if you have a spacecraft performing the same mission, odds are it's going to have a similar configuration. The thing that makes them look most similar is the navigation signal antenna array (the "Willy Wonka Chocolate Factory"). Even those are slightly different between the two models. But since they're fundamentally performing the same function, thye look very similar ("form follows function").

Re:You Will Be Assimilated! (1)

AKAImBatman (238306) | more than 8 years ago | (#13650978)

But if you have a spacecraft performing the same mission, odds are it's going to have a similar configuration. The thing that makes them look most similar is the navigation signal antenna array (the "Willy Wonka Chocolate Factory").

Fair enough. I was actually looking at the general shape of the craft, and also was influenced by the story which suggests that the new sats are simply updates of the old ones. On further inspection, it does appear that the two sats are quite a bit different.

Speaking of which, I am wondering what the heck those things on the antenna array are. (Assuming for a moment that they aren't coverings for classified equipment or even just "neat" coverings for publicity photos.) The more squat ones are reminicent of capacitors, but I'm not certain why you'd put them outside of the chassis (i.e. fully exposed) as opposed to inside. The candy-cane style ones look like they're just coverings for antennas. Any ideas?

Re:You Will Be Assimilated! (5, Informative)

josecanuc (91) | more than 8 years ago | (#13651035)

Speaking of which, I am wondering what the heck those things on the antenna array are.

Those *are* the antennas. See the spiral bits on both kinds? That's a conductive strip. It's a helical antenna -- common on satellites. The body that looks like the main bulk is just to give the thin metal something to hold shape.

Re:You Will Be Assimilated! (1)

AKAImBatman (238306) | more than 8 years ago | (#13651101)

I didn't realize that, especially since the new sat seems to have other atennas similar to the NAVSTAR. Thanks for the info! Learn something new everyday. :-) (Mods, please mod parent up "informative".)

Re: It's a retrofit! (1)

belchingjester (529389) | more than 8 years ago | (#13650902)

From TFA, the 2R series were already built, but the opportunity was taken to retrofit the last 8 with upgraded capabilities. The last place I would retrofit would be the chassis...

Re:You Will Be Assimilated! (3, Interesting)

speculatrix (678524) | more than 8 years ago | (#13650998)

there has been a tremendous increase in miniturization and technology since the original GPS sats

your statement is naive in that it supposes that mil-spec and rad-hardened technology has advanced at the same rate. Once, it was the military who led the way and consumer devices followed; now, it's the other way round, and in fact the military/space people have big problems with obsolescence, especially with the recent EU rules on Reductions Of Hazardous Substances (often known as "lead free", but actually covers other things as well). In some instances, military kit is being forced to use automotive-spec components as replacements, because that's all that's available and at least the devices have a wider temperature range.

so, yes, mil- and space-spec hardware is advancing, but the testing cycle is far longer - think months rather than weeks. when you're spending $M's in launch fees, you've got to get it right!

Re:You Will Be Assimilated! (1)

AKAImBatman (238306) | more than 8 years ago | (#13651055)

Once, it was the military who led the way and consumer devices followed; now, it's the other way round, and in fact the military/space people have big problems with obsolescence

It's still quite advanced equipment, though. Sure, we're not talking about gigahertz processors and multi-gigabyte memory architectures. Instead, we're talking about old Sparcs, Pentiums, and MIPS from days gone by. That's still pretty advanced stuff. And when it comes to the batteries, LiON batteries were actually developed for space use [nasa.gov]. As for the propulsion, arcjets and ion engines are new technologies that have proven themselves in real satellite usage.

So yes, some stuff is behind the commercial market. But there's still plenty of highly advanced techology that's been rated for space use. :-)

Re:You Will Be Assimilated! (1)

bleckywelcky (518520) | more than 8 years ago | (#13651148)

You could say the same for the Model T and Ford's latest Mustang. I mean, they both have wheels, right? They both have engines, right? They both have doors, right? Well, they must have not changed much in the design. Hell, what are we paying these morons for?

The overall layout of a GPS antenna is not going to change much, you're always going to have to shoot your signal in a certain direction. However, the efficiency of the components and the effectiveness of the materials has all been re-engineered. As well, I'm sure the bus is being continually improved.

Normal people hate linux (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#13650472)

Linux is *not* user friendly, and until it is linux will stay with >1% marketshare.

Take installation. Linux zealots are now saying "oh installing is so easy, just do apt-get install package or emerge package": Yes, because typing in "apt-get" or "emerge" makes so much more sense to new users than double-clicking an icon that says "setup".

Linux zealots are far too forgiving when judging the difficultly of Linux configuration issues and far too harsh when judging the difficulty of Windows configuration issues. Example comments:

User: "How do I get Quake 3 to run in Linux?"
Zealot: "Oh that's easy! If you have Redhat, you have to download quake_3_rh_8_i686_010203_glibc.bin, then do chmod +x on the file. Then you have to su to root, make sure you type export LD_ASSUME_KERNEL=2.2.5 but ONLY if you have that latest libc6 installed. If you don't, don't set that environment variable or the installer will dump core. Before you run the installer, make sure you have the GL drivers for X installed. Get them at [some obscure web address], chmod +x the binary, then run it, but make sure you have at least 10MB free in /tmp or the installer will dump core. After the installer is done, edit /etc/X11/XF86Config and add a section called "GL" and put "driver nv" in it. Make sure you have the latest version of X and Linux kernel 2.6 or else X will segfault when you start. OK, run the Quake 3 installer and make sure you set the proper group and setuid permissions on quake3.bin. If you want sound, look here [link to another obscure web site], which is a short HOWTO on how to get sound in Quake 3. That's all there is to it!"

User: "How do I get Quake 3 to run in Windows?"
Zealot: "Oh God, I had to install Quake 3 in Windoze for some lamer friend of mine! God, what a fucking mess! I put in the CD and it took about 3 minutes to copy everything, and then I had to reboot the fucking computer! Jesus Christ! What a retarded operating system!"

So, I guess the point I'm trying to make is that what seems easy and natural to Linux geeks is definitely not what regular people consider easy and natural. Hence, the preference towards Windows.

Re:Normal people hate linux (-1, Offtopic)

Onymous Hero (910664) | more than 8 years ago | (#13650730)

Linux packaging technology beats the ass of windows any time. I can click double click on .debs and get them openened by a installer just like .msi

The problem is in how they're delivered and the lack of 1) a common packaging format and 2) lack of a common "package namespace" (ie: xorg can be called xorg in fedora and xserver-xorg in debian, that makes dependencies fail and can be only fixed by using a common packaging framework where developers and not distros makers package things)

But Linux continues being much better than windows in some areas. For example, you've to download the .exe programs from docens of differents web pages. This becomes SCARY when you've to update things. For the vast majority of software you've to check for new versions visiting their web page and reading the text to check visually if there's a new version. Compare it to the magic of apt-get and emerge....I wonder when Microsoft will catch up with the early 90's and will develop a new .msi format where developers can suministrate a URL for a XML file which tells Windows what are the latest file versions of a given program...there're hints that makes me believe that they'll use RSS for this in Windows Vista, but I don't expect that much from microsoft...

Compatibility (3, Interesting)

slimey_limey (655670) | more than 8 years ago | (#13650479)

Will this improved accuracy come at the cost of compatibility? I already have a GPS reciever, and I don't want to have to buy a new one to make my data more accurate. (Magellan hasn't released new firmware for the SporTrak Basic since 2002, and I'm not holding my breath.)

Re:Compatibility (4, Interesting)

AKAImBatman (238306) | more than 8 years ago | (#13650533)

The new civilian channel is in addition to the existing channel, so your existing equipment should work. As more of these sats go online, you can expect to see gear that provides access to the second civilian channel. (Source [rin.org.uk])

What I have to wonder, though, is what will they do with the two new military channels? It seems that all the field soldiers tend to use civilian gear because the military gear is too heavy, unfriendly, ugly, and is in short supply. I suppose it would make the missiles hit their targets better, but it would be nice to know that our entire military can use the equipment.

Re:Compatibility (1)

geoffspear (692508) | more than 8 years ago | (#13650552)

When they turn off the civilian channel, you can bet the military is still going to be using their channels.

Re:Compatibility (1)

Xaositecte (897197) | more than 8 years ago | (#13651450)

They can't turn off the civilian channel.

Not without making all those Y2K nightmare fears come true.

Re:Compatibility (3, Informative)

Wyatt Earp (1029) | more than 8 years ago | (#13650573)

In each squad I think there is a military grade GPS reciever, since Afghanistan and more so, Iraq, more and more soldiers are carrying thier own GPS hand held which is good enough for field work.

The new military channels will be more for JDAM/Cruise Missiles and other targeting systems.

Re:Compatibility (0)

Anonymous Coward | more than 8 years ago | (#13651390)

What I have to wonder, though, is what will they do with the two new military channels?

One for them, one for their "allies"?

FANTASTIC !! (0, Troll)

Artie_Effim (700781) | more than 8 years ago | (#13650498)

Now I can tell exactly where I am when I'm driving my car while looking at my on-board GPS mapping system !! Now my friends will be able to tell to 30cm accuracy where 'I'm at' when they call on my GPS enables phone!! Even better, we can now more easily track those Mexican state officals as their bodies are being transported by drug kingpins!! W00T I saw at this great advancement of technology that renders us unable to hide from out mothers, enjoy the scenery while getting lost, knowing EXACTLY what our kids are up to, where our spouses are. I for one do not welcome out new GPS enabled overloards.

Combining articles (0)

Anonymous Coward | more than 8 years ago | (#13650510)

Read a couple of days ago about a jamming satellite and now a jam-proof satellite is launched. Are we going to jam the Galileo system? Do the Europeans have to read road signs again?

Jamming, eh? (0, Offtopic)

gowen (141411) | more than 8 years ago | (#13650511)

Because of the risk of Jamming, I forsee an Exodus from old GPS to new, throwing Caution to the wind, putting the alternatives in Crisis. As long as tech can Keep On Moving, I'm going to be in a Mellow Mood, and won't Mix Up, Mix Up these services. After just One Cup Of Coffee (add One Drop of milk, Stir It Up...), I can feel the Positive Vibration this has given me, and Time Will Tell that that Slave Driver of a boss will be Waiting In Vain for my report. Work, Why Should I with So Much Trouble In The World?

Thank You Lord. The score is now One-Love to the DoD.

Jamming by whom? (3, Informative)

moz25 (262020) | more than 8 years ago | (#13650513)

As I understand, one of the jamming related problems with GPS is not by criminals/terrorists, but by the government when they see the need. It seems more of a political than a technical nature. That's one of the potential benefits of the Galileo system: to have more than one "supplier" of such information.

Re:Jamming by whom? (3, Informative)

AKAImBatman (238306) | more than 8 years ago | (#13650580)

As I understand, one of the jamming related problems with GPS is not by criminals/terrorists, but by the government when they see the need.

No, it's more complex than that. Yes, the government can fine tune the results to cause problems for enemies, and even turn off the unencrypted civilian bands if they so choose. However, real methods exist [wikipedia.org] for sending confusing signals that will effectively jam a GPS signal. This jamming can force so called "smart bombs" to rely on internal guidance instead of GPS. The result (hopefully) is that the less precise guidance would cause the bomb or missile to miss the target.

In practical terms, it seems a bit harder than that to prevent US munitions from reaching their targets. Our guidance computers were well developed prior to the general use of GPS coordinates, and we have the capability to manually deliver ordinance wherever it may be needed. So in the end, this is about keeping the efficiency of our weapons in good order so that we have to risk fewer lives in missed targets and strafing runs.

Re:Jamming by whom? (4, Insightful)

Dun Malg (230075) | more than 8 years ago | (#13650754)

However, real methods exist for sending confusing signals that will effectively jam a GPS signal. This jamming can force so called "smart bombs" to rely on internal guidance instead of GPS. The result (hopefully) is that the less precise guidance would cause the bomb or missile to miss the target.

Problem with active GPS jamming is that it's a "damned if you do, damned if you don't" situation. Any sort of active jamming on the battle field is a huge beacon on the battlefield screaming BLOW ME UP! It then becomes a question of whether or not to turn on the jammer at all, as at most it'll be good for slightly de-accurizing (if that's not a word, it ought to be) one bombing run before being obliterated. If they were cheap enough, maybe, but even still...

Re:Jamming by whom? (4, Informative)

w42w42 (538630) | more than 8 years ago | (#13650817)

I remember watching a press conference with a military general at the opening of the last gulf war. The press was all lathered up about reports that Iraq was jamming GPS signals - it was assumed the Russians had given them the equipment - and the general commented that whoever was running that equipment had the worst job with the shortest life expectancy in the world at that time. Like you alluded to, any military equipment that relies on an outgoing radio signal instantly becomes a big bright target.

Re:Jamming by whom? (2, Informative)

nsayer (86181) | more than 8 years ago | (#13651309)

any military equipment that relies on an outgoing radio signal instantly becomes a big bright target.

Yup [navy.mil].

And I rather suspect that HARMs are not limited to air defense radar systems...

Re:Jamming by whom? (1)

NatasRevol (731260) | more than 8 years ago | (#13651367)

Unless that target is another satellite. Say a second generation of GPS that is, strangely, heavier than the first generation.

There aren't many countries in the world that can quickly and accurately take out a satellie that is beaming a jamming signal.

Re:Jamming by whom? (1)

soft_guy (534437) | more than 8 years ago | (#13651066)

Can they not use multiple stations to make it appear the signal is coming from a place where it is not?

Re:Jamming by whom? (2, Interesting)

Dun Malg (230075) | more than 8 years ago | (#13651475)

Can they not use multiple stations to make it appear the signal is coming from a place where it is not?

No, all that would do is present multiple individual targets. Modern direction finding equipment uses such advanced digital processing that it can separately identify two transmitters right next to each other based on subtle differences between them caused by things like inherent manufacturing variations in the transmitters' modulation circuitry.

Re:Jamming by whom? (1)

spankus (140336) | more than 8 years ago | (#13651067)

Actually, because of the incredibly low power GPS transmits at...it is possible to design a GPS jammer that broadcasts BELOW the ambient noise floor that will still impact GPS receivers.

Sparkus

Re:Jamming by whom? (0)

bluGill (862) | more than 8 years ago | (#13651286)

True, but there is little point in battle field jamming of GPS. Anyone with a set of eyes (last I checked military refuse the blind) can navigate to any ground target with just a map, which cannot be jammed. (A compass helps, as do stars and the sun, all of which are hard to jam. Still dead reckoning just by knowing your original direction is often to get there) Targets are visible from miles away. A city doesn't move, and can often be seen 30 miles away or more. Targets that do move need those eyes anyway because the GPS can at best take you to where it was.

The purpose of jamming GPS is for missiles. If the Soviet Union launched a ICBM at a US city, using GPS, jamming the signal is enough to make the missile most likely to hit farmland outside the city. Bad for the farmer, but much less deaths than hitting the city (or whatever the target is). Of course the Soviet Union is long gone, and nobody else has ICBMs, so there is no point in jamming GPS anymore - at least not for anyone with the ability to pull it off. In fact the US wants the bad guys to think GPS is not jammable (and it is hard to do), in hopes that they will cheat and use GPS for misstel guidance - then after the launch they turn on selective ability, and the misstel lands in a relatively harmless area.

Re:Jamming by whom? (0)

Anonymous Coward | more than 8 years ago | (#13651334)

Yeah, I was looking for someone else saying that. As soon as you broadcast that signal, Sam Fisher [splintercell.com] is gonna show up, grab you from behind, and hold a knife to your throat until you tell him the four-digit password to the computer controlling the transmissions.

Hey, that should be a mission in the next Splinter Cell. Instead of shutting it down, readjust it so it actually augments the real GPS signal.

...Pardon, been playing a bit too much Chaos Theory lately. :P

Re:Jamming by whom? (1)

turbotalon (592486) | more than 8 years ago | (#13651079)

Smart bombs themselves do not directly rely on GPS. The aircraft they are released from gets a solid fix before dropping the bomb, then the bomb relys on intertial guidance. I would think it would be pretty obvious to the pilot/bomber that his GPS was being jammed and his position was freaking out. Also, once the bomb is dropped, it will be accurate even if the whole GPS system went down.

I see jamming in action regularly (4, Informative)

RebornData (25811) | more than 8 years ago | (#13650997)

I use a laptop-integrated GPS in my car, and I drive by the Pentagon regularly for work. The GPS goes nuts on certain roads that pass near the building... the "position" of the vehicle jumps all over the place. Same thing happens near the capitol building. No suprise of course...

-R

Sideeffects of faults in "other" system (1)

FerretFrottage (714136) | more than 8 years ago | (#13651349)

The GPS system that is really jammed in the cases you see (by the various government buildings) is the other GPS: Government Political System. That system, whether is be the Demo or Repub version always seems to have problems.

Re:I see jamming in action regularly (1)

SlayerofGods (682938) | more than 8 years ago | (#13651501)

How effective would that jamming really be.... since anyone smart enough to build a cruise missile that could use GPS for guidance would be equally intelligent enough to build a cruise missile to simply home in on the jamming single it's self. Or even with out that could simply free fly the last little distance around the jammer and still hit extremely close to the target.
And if your talking about a suicide attacker in a plane; how exactly is losing your GPS location when your within visual range of your target going to stop you.....
What exactly are they trying to protect against?

Home Made Cruise Missiles !!! (0)

Anonymous Coward | more than 8 years ago | (#13650523)

The downisde, of course, is that "Crimson Jihad" or whoever can now make cheap cruise missiles to shoot at us.

Re:Home Made Cruise Missiles !!! (1)

ghukov (854181) | more than 8 years ago | (#13650558)

like this [interestingprojects.com] one? The public channels are off to a certain degree so they wouldn't be able to accurately target what they want to hit. But I imagine if the payload is large enough, the "splash damage" could wreak some havoc

Signal jamming==profit (1, Interesting)

jurt1235 (834677) | more than 8 years ago | (#13650553)

Step plan to GPS signal jamming profit:
1. Launch GPS satellites and sell lots of GPS devices
2. Launch jamming satellite (last week news)
3. Launch new GPS satellite system which is less prone to jamming
4. Sell new receivers => profit!

Re:Signal jamming==profit (0)

Anonymous Coward | more than 8 years ago | (#13651351)

correction:

1. Launch GPS satellites and sell lots of GPS devices
2. Launch jamming satellite (last week news)
3. Launch new GPS satellite system which is less prone to jamming
4. Sell new receivers
5. repeat 2-4 => profit!

Its about time (2, Insightful)

dj245 (732906) | more than 8 years ago | (#13650568)

The sattelites up there are fairly old. Some of the newer ones were launched only a couple years ago, but some have been up there since the early 90's or before. We've had the math equations and the computing technology to be able to put up satelites with around 1m accuracy and better signal strength for a couple years now. Forget about the better jamproofing; with the newer eqipment you can sum the error of your integrals with newer algorithms and faster and determine position that much better less error-prone initial conditions.

Re:Its about time (0)

Anonymous Coward | more than 8 years ago | (#13651065)

Holy crap does that last sentence hurt the baby Jesus.

Re:Its about time (2, Insightful)

spankus (140336) | more than 8 years ago | (#13651114)

Do you upgrade your computer every time a new processor comes out????

Same reasoning (sorta) applies to GPS. Why throw away a $100,000,000 satellite when it hasn't died yet?

The newer satellites do have some expanded capabilities, but don't plan on seeing those operationally for 5 to 8 years. (It's a long story of governmental mismanagment and strife)

How do you compete with vaporware (Galileo)? (5, Insightful)

Anonymous Coward | more than 8 years ago | (#13650588)

" The government is now competing with Europe's Galileo system "

Lets see :
        Galileo has not launched yet.
        Galileo will not be free.
        The 2R-M was planning before Galileo was anounced.
        Galileo operational capibility is not planned until 2008.

I'm failing to see the link to the vaporware...

Re:How do you compete with vaporware (Galileo)? (0)

Anonymous Coward | more than 8 years ago | (#13650673)

this is once again the proof that we need competition.

if GPS doesn't want to be out of business, they need to update NOW.

Re:How do you compete with vaporware (Galileo)? (1)

torpor (458) | more than 8 years ago | (#13650732)

where does it say none of those things will happen? its possible to compete, and yet your competitor isn't in the race. YET.

Besides... the U.S. has their jammer satellite (1)

Animaether (411575) | more than 8 years ago | (#13650870)

U.S. Deploys Orbital Communications Jammer [slashdot.org]

so even if Galileo were up, etc. who cares ? the U.S. can just jam them all ;)

or, heck, if need be - shoot them with a rocket. Be a bit debris-rich in result, though, which isn't very desirable

Re:Besides... the U.S. has their jammer satellite (1)

Sanity (1431) | more than 8 years ago | (#13650985)

Come on, almost any industrialised nation, including many if not all countries in the EU, Japan, and others, could shoot the GPS system out of the sky within the first few hours of any war. These navigation systems only ever exist with the consent of other powerful nations.

Re:Besides... the U.S. has their jammer satellite (1)

ckaminski (82854) | more than 8 years ago | (#13651076)

Actually, I'd wager that Russia and perhaps one or two of the other ex-Soviet Republics have the technology to hit a target at 10,000km. Whether or not they'd have 20-30 missiles capable of doing it is something entirely different, when you'd probably want to be lobbing nuclear weapons at your enemy instead.

Re:Besides... the U.S. has their jammer satellite (1)

mforbes (575538) | more than 8 years ago | (#13651293)

Sure, but why bother trying to hit the satellites at all when simply lobbing a few nukes into the ionosphere does the job just as well? (Granted, you destroy your own communications abilities at the same time, but hey, it's not like they'll outlast an all-out nuclear war anyway...)

Re:Besides... the U.S. has their jammer satellite (0)

Anonymous Coward | more than 8 years ago | (#13651469)

I'd not be surprised if the Russians couldn't fry the electronics in a GPS satellite (or any other) with a land-based particle beam weapon. No need for missiles.

Re:How do you compete with vaporware (Galileo)? (3, Informative)

Anonymous Coward | more than 8 years ago | (#13651011)

Having worked on the Galileo internal operating software, i can say operation in 2008 is somewhat optimistic.

Re:How do you compete with vaporware (Galileo)? (1, Funny)

Anonymous Coward | more than 8 years ago | (#13651480)

Hey, it's a European co-operation; we'll be lucky if we see it before 3008. It'll take 50 years just to translate the manual into all 15 languages.

which # (2, Insightful)

allelopath (577474) | more than 8 years ago | (#13650591)

Is there a way to know which # (1..24) this one is replacing?
Just curious...it would be fun to know when i turn on my GPS receiver.

Re:which # (3, Informative)

Ossifer (703813) | more than 8 years ago | (#13650670)

From TFA:

GPS 2R-M1 will assume the Plane C, Slot 4 position, taking over for the GPS 2A-20 craft launched in May 1993.

Re:which # (0, Redundant)

Feyr (449684) | more than 8 years ago | (#13650681)

from the article:

GPS 2R-M1 will assume the Plane C, Slot 4 position, taking over for the GPS 2A-20 craft launched in May 1993.

Re:which # (2, Interesting)

Toaste (892190) | more than 8 years ago | (#13650803)

From the article: "GPS 2R-M1 will assume the Plane C, Slot 4 position, taking over for the GPS 2A-20 craft launched in May 1993."

From the designation of the old satellite, I presume that this position is number 20 on GPS receiving equipment. Just a guess.

By the way, does anybody know how they plan to move the old one out of the way? According to info found here [astronautix.com] the origional was a 3-axis stabilized NAVSTAR, but I doubt it will be able to move significantly with only its thrusters.

Another interesting point: the page lists the design life of this series at 7.5 years. Which means this satellite was replaced a mere 4 years, 10 months, and 13 days beyond its expected service life.

Re:which # (1)

allelopath (577474) | more than 8 years ago | (#13650932)

>> I presume that this position is number 20 on GPS receiving equipment. Just a guess. i didn't know for certain, either, which is why i asked

Re:which # (4, Informative)

Hrdina (781504) | more than 8 years ago | (#13651153)

Actually, it will appear as PRN (pseudo-random noise) #17 on receiving equipment. That PRN is currently unused. The current vehicle in slot C4 is PRN07, and it will keep that PRN assignment until it is decommissioned by the USAF.

Too Little Too Late (3, Funny)

qwp (694253) | more than 8 years ago | (#13650624)

I would have been able to post first post,
had i known about this great achievement. The problem is
I was suck in my car cause I took a wrong turn due to my
dam'ed gps navigator. Maybe they haven't turned it on yet..

Re:Too Little Too Late (0)

Anonymous Coward | more than 8 years ago | (#13650874)

It takes more than good GPS to get first post. The first thing you should do is quit your job, because employment will seriously hamper your ability to get first post. Then, of course, you will probably have to live in your mother's basement, since you don't have any money, but no one ever said being a first post whore was easy...


--
__________
|rip/\/\aster /\/\onkey

Jamming (0)

big.iron.wiz (773525) | more than 8 years ago | (#13650630)

Pardon my english, but does this have anything to do with throwing jamm at satelites and is that why they don't use rockets and started using plannes to throw satelites?

Specs? (2, Interesting)

adminispheroid (554101) | more than 8 years ago | (#13650818)

Anybody know what's on the new civilian channel? e.g. is it the same kinda stuff as the two existing channels, on a new carrier? Or is it a new code?

Re:Specs? (4, Interesting)

Anonymous Coward | more than 8 years ago | (#13650966)

The new civilian code is probably a longer signal that repeats less often. This gives better accuracy but takes longer to determine position when first switched on. Using the lower accuracy signal would allow for a rapid first estimate of postion while the GPS would become more accurate once the position using the new signal was calculated. The military GPS systems use the civilian signal to estimate their position more quickly.

First Modernized? (0)

Anonymous Coward | more than 8 years ago | (#13650828)

I know it's nitpicking but.. redundant a little? Isn't this a true statement any time we release a new version of anything that isn't an exact copy of what the previous version was?

New GIS+RS website! slashgisrs.org (1)

Lord Satri (609291) | more than 8 years ago | (#13650923)

Humm, I'll start stealing slashdot's content for our new slashsite! :-)

Want to discuss GPS stuff or anything related to geospatial like GIS and Remote Sensing, visit the brand-new http://slashgisrs.org/ [slashgisrs.org] website. Ad-free and non-for-profit.

It has just launched (last friday afternoon), so plenty of low uid still available ;-)

competing? (0, Redundant)

MooseTick (895855) | more than 8 years ago | (#13650948)

"The government is now competing with Europe's Galileo system"

It is also competing with the gps system I am building in my garage and will launch from my backyard in 2015.

The European system hasn't left the ground yet. Let's not call it competing until it is functioning. Also, how are they competing? Does the US system make money?

Re:competing? (1)

pasword *** (824184) | more than 8 years ago | (#13651231)

Does the US system make money?
Aren't the largest suppliers of gps products American companies? They pay taxes...

Russians using GPS (2, Interesting)

Thagg (9904) | more than 8 years ago | (#13651081)

I was fairly astonished to see in the recent issue of Aviation Week that Russia is now building GPS-guided bombs. Presumably this is just using the civilian signal, which could be disabled or degraded in a conflict theater -- but still, it was an fairly amazing development. I suppose that it's conceivable that AvWeek got the facts wrong, and that it was a GLONASS-guided bomb, but they're usually pretty good about that sort of thing.

Thad Beier

accuracy improvement? (1)

spectrokid (660550) | more than 8 years ago | (#13651182)

I read that the improved accuracy from Gallileo will be because, apart from the low-orbit sats, there will also be geostationary ones helping the low-orbit ones to determine their own position. If this is correct, just a technology upgrade should not improve accuracy that much. Anybody any numbers?

We need more GPS satellites (4, Informative)

Animats (122034) | more than 8 years ago | (#13651456)

We've recently been struggling with a Novatel GPS that receives Omnistar High Precision corrections, and supposedly provides 15cm accuracy. The problem is that it needs to see at least five GPS satellites for Omnistar HP to work. Regular GPS requires only four, but the ionospheric corrections for Omnistar require some redundancy. Five sats are the minimum; six are better.

Unless you're in a very flat area, in the air, or on an ocean, you won't see five or six sats 100% of the time. 70-80% is more like it. If one of the sats is down (which happens; PRN #5, plane B, slot 4, wss down for 8 days recently [uscg.gov]), the outages are longer.

GPS uses six rings of four satellites each, with all rings in polar orbit. The four satellites in each ring are 90 degrees apart. So, when a satellite in a ring is near the zenith, it's usually the only one visible in that ring. The original design called for more satellites per ring; with six per ring, you'd always have at least two satellites visible per ring, as long as you could see to within 30 degrees of the horizon. But there was a budget cut in the early days of GPS.

Load More Comments
Slashdot Account

Need an Account?

Forgot your password?

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>
Sign up for Slashdot Newsletters
Create a Slashdot Account

Loading...