On Fri, 03 Oct 2003 01:51:51 GMT, "Scott Lowrey"
wrote:

You can't get RAIM forecasts from a receiver, right? The
receiver can only confirm integrity "right now".

You can get RAIM forecasts from a receiver (or the simulator). It
knows where all of the satellites are located at any time in the
future. If you provide a location to the RAIM and a time to the RAIM
prediction screen, it will tell you if the satellite geometry will
give you satisfactory reception. It will not tell you if a satellite
is scheduled to be out or DOD is jamming (that is the function of
NOTAMs). Nothing will tell you if there will be an unscheduled outage
because of equipment failure or atmospheric conditions. That is why
all IFR certified GPS systems must provide RAIM warnings.