I
Ian Rawlings
Guest
On 2005-06-10, Peter <[email protected]> wrote:
> It's no good just denying it will ever happen.
We're talking about our world, not pixie-land.
> If Tim keeps saying it won't or can't, he may be right but he more than
> likely will be wrong.
You on the other hand, are far more accurate; you're entirely wrong,
which beats Tim's "maybe wrong" any day.
> GPS is already two way as we use it on marine position finders to
> add pinpoint accuracy. It's called SdGPS (Satellite Differential
> GPS).
.... which works by RECEIVING a signal from a beacon with a known
position and using that to bring the accuracy up from about 10 metres
to about 5 metres, with WAAS it can be 3 metres. But this is in open
space, you need three or four widely spaced satellites to achieve
that, in a city errors are much higher because the only satellites you
can see are likely to be close together.
If you had any idea about how radio works you'd realise that millions
of cars transmitting to satellites would all require their own
frequency or would require precise multiplexing syncronised to
picosecond accuracy across thousands of cars. This would eat up the
radio spectrum in no time. As I said in a previous post, if they want
to transmit anything they'd more likely use mobile networks or pager
networks which work on a cellular basis avoiding the frequency
spectrum problem.
I expect that if you want to stick to your two-way satellite theory
you'll probably point to two-way satellite internet or phones to
support your idea, however these use aerials positioned to point to a
specific satellite allowing the same frequency to be used on others,
this isn't possible with a moving car without gyroscopically
stabilised radomes on top of the car, which I think we'd notice. Even
if we didn't notice a 12-inch dome on the tops of our cars, this
method still wouldn't allow millions of cars to be tracked as it still
wouldn't reduce the need for frequencies down to a manageable level.
> The technology is already there and some is already in use.
Maybe, but not using the technology you think. If you go to Northern
Ireland you'll find that GPRS is extremely fast and reliable and
mobile phone signals are surprisingly good. There was a huge
investment programme in communications systems in NI to aid in setting
up remote cameras and number plate tracking systems to help hunt down
wanted people. They don't use two-way satellite traffic.
> It's too simplistic to say that the system can easily be jammed. If
> it's not receiving a signal the car won't start!
You're making this up on the hoof, and not very well.
> The only way round it is to go outlaw. With no tax, insurance, MOT
> or GPS spy in the car.
Or walk. Or wear a tin hat and lead underpants.
> It's probably the easiest solution. Seems to work well for our foreign
> friends who kill pedestrians and then get off with a fine for dangerous
> driving.
Oooooh those nnnnnnnaughty foreigners!
> Peter
Peter is slang for 'penis', I sense a conspiracy here!
--
For every expert, there is an equal but opposite expert
> It's no good just denying it will ever happen.
We're talking about our world, not pixie-land.
> If Tim keeps saying it won't or can't, he may be right but he more than
> likely will be wrong.
You on the other hand, are far more accurate; you're entirely wrong,
which beats Tim's "maybe wrong" any day.
> GPS is already two way as we use it on marine position finders to
> add pinpoint accuracy. It's called SdGPS (Satellite Differential
> GPS).
.... which works by RECEIVING a signal from a beacon with a known
position and using that to bring the accuracy up from about 10 metres
to about 5 metres, with WAAS it can be 3 metres. But this is in open
space, you need three or four widely spaced satellites to achieve
that, in a city errors are much higher because the only satellites you
can see are likely to be close together.
If you had any idea about how radio works you'd realise that millions
of cars transmitting to satellites would all require their own
frequency or would require precise multiplexing syncronised to
picosecond accuracy across thousands of cars. This would eat up the
radio spectrum in no time. As I said in a previous post, if they want
to transmit anything they'd more likely use mobile networks or pager
networks which work on a cellular basis avoiding the frequency
spectrum problem.
I expect that if you want to stick to your two-way satellite theory
you'll probably point to two-way satellite internet or phones to
support your idea, however these use aerials positioned to point to a
specific satellite allowing the same frequency to be used on others,
this isn't possible with a moving car without gyroscopically
stabilised radomes on top of the car, which I think we'd notice. Even
if we didn't notice a 12-inch dome on the tops of our cars, this
method still wouldn't allow millions of cars to be tracked as it still
wouldn't reduce the need for frequencies down to a manageable level.
> The technology is already there and some is already in use.
Maybe, but not using the technology you think. If you go to Northern
Ireland you'll find that GPRS is extremely fast and reliable and
mobile phone signals are surprisingly good. There was a huge
investment programme in communications systems in NI to aid in setting
up remote cameras and number plate tracking systems to help hunt down
wanted people. They don't use two-way satellite traffic.
> It's too simplistic to say that the system can easily be jammed. If
> it's not receiving a signal the car won't start!
You're making this up on the hoof, and not very well.
> The only way round it is to go outlaw. With no tax, insurance, MOT
> or GPS spy in the car.
Or walk. Or wear a tin hat and lead underpants.
> It's probably the easiest solution. Seems to work well for our foreign
> friends who kill pedestrians and then get off with a fine for dangerous
> driving.
Oooooh those nnnnnnnaughty foreigners!
> Peter
Peter is slang for 'penis', I sense a conspiracy here!
--
For every expert, there is an equal but opposite expert
