GPS - Selective Availability to be Turned Off?

GPS - Selective Availability to be Turned Off?

Post by John Freit » Sat, 01 Mar 1997 04:00:00

cut...

Quote:> The DGPS units that are precisely located also contain a transmitter
> to transmit correction values according to the RTCM SC-104 standard.

...

Correct as far as it goes.  The US Coast Guard has equipped many of its LF
beacon transmitters (2 to 300kHz) to broadcast Differential correctors to a
range of about 200NM plus or minus.  Most of the US East coast, Gulf coast
and West coast are covered.  Ther service is free and most GPS receivers
are equipped to accept the RTCM-104 signals with the added receiver. For
teresterial use you local easy listning FM station may broadcast DGPS
correctors to a pager like receiver, for a price.  The cost is about
$.50/day for 10 M accuarcy,  5 and 1M accuracy comes at a somewhat higher
cost.

For the record, P-code accuracy is stated at 17.1M rms.

John Freitag

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THE REPLY, OF COURSE, DOES NOT REPRESENT ANY OFFICIAL POSITION OF THE
UNIVERSITY, only my personal opinion.