In article "Paul Remde" writes:
Hi,

I have a technical question. Next week at the SSA Convention many vendors
(myself included) will have many soaring instrument demos on display. It
would be great if they could be locked onto GPS satellites, but that is not
likely inside the convention hall. I imagine the roof is made of metal.
The moving map displays will display more interesting information when
locked onto satellites. Also, the all the FLARM units in the room would
show up on the moving map displays - but only if the FLARMs and the moving
map displays are locked-onto GPS satellites.

Is there a technical solution to that issue? Could a receiver be mounted
somewhere that receives, amplifies or re-directs and rebroadcasts the GPS
signals for use inside the hall?

However, all of the receivers will show position computed at the location
of the outside receiver antenna, with time offset by the delay through the
system and the inside path.

The FLARM units will show everyone in the same place.

Also, from the separately referenced http://www.gpssource.com/GPS-Retransmission:

The FCC regulates the GPS signal. Retransmission systems are only
available to International Customers (outside the U.S.), agencies of the
US Federal Government, parties operating under the direction of the US
Federal Government, or parties that have received an STA or Experimental
License under part 5 of the FCC rules, or parties that will be operating
GPS Repeaters in an anechoic chamber.

Alan