Re: [Melb] POTS (Position of Trains System)

[Richard <richard_snook@primus.com.au>]

Without cutting to fine  a line... whether its the preeferred 10ft or 20m  GPS will let you know where something
is...passing over transponders would I presume give a last known position type indication ....unless thee is some other
form of interaction between the devices on the track and on the trains....even at 20m   youhave a prety good idea where
something IS as opposed to introducing a little of the >>"well its somewhere between here and there"...that might work
onsome lines between some stations but its a shot in the dark on others!!

cheers >:~)) Richard

Dave Proctor wrote:
> 
> Richard <richard_snook@primus.com.au> wrote in message
> 3830DC58.7F200683@primus.com.au">news:3830DC58.7F200683@primus.com.au...
> > DOes the current system employ a true GPS system...ie train is tracked (no
> pun intended) as per normal GPS to say within
> > 10feet??
> 
> Isn't that DGPS (Differentil Global Positioning System)> GSP is only valid
> to approx 20 metres or so. unless on the military band. There are ways
> around this though (DGPS is one of them).
> 
> --
> DaveProctor
> thadocta AT dingoblue.net.au