First modernized GPS satellite Launched

A reader 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."

Its about time

[dj245]

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.

How do you compete with vaporware (Galileo)?

[Anonymous Coward]

" 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...

which #

[allelopath]

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:Look everyone! Somone who didn't RTFA!

[cerberus4696]

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:Jamming by whom?

[Dun Malg]

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:Look everyone! Somone who didn't RTFA!

[GileadGreene]

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!

[cpu_fusion]

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:Its about time

[spankus]

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)

Re:You Will Be Assimilated!

[GileadGreene]

IMHO it comes down to 3 things (one of which you've already captured):

1. It takes a long time to get a satellite up, and chasing new technology will just make it take longer.
2. It is not a given that a new technology will provide benefits for a given mission. There are interactions between different elements of the design that may mean that a certain technology is not appropriate for the mission in question (the demands of EP on solar arrays being a prime example of this kind of negative interaction).
3. The temptation is always to cram as much capability as possible into the satellite, instead of providing the minimum capability required. This is especially true of government satellites since the requirements are typically ill-defined to begin with (at least in my experience).

These reasons apply to US government space programs. For an alternative approach, you might look at Surrey Satellite Technologies Ltd [sstl.co.uk] in the UK. They build and launch things quickly, have a well-defined strategy for integrating new technologies into spacecraft in a low-risk fashion and getting rapid flight-test information on them, make good use of the technologies appropriate to a mission instead of getting wedded to any one tech, and are extremely good at nailing down their requirements and building only what is needed. IMHO they are the best, and most innovative satellite manufacturer in the world today (and no, I don't work for them - although I'd do so in a heartbeat if I ever moved to the UK).

To being things slighly back on-topic, it's probably worth noting that SSTL has the contract to develop a testbed satellite [sstl.co.uk] for the Galileo system (the European competitor to GPS).