Actually, geosynchronous satellites are at the higher altitudes. You might have the two mixed up - the polar orbiting satellites might require more than one pass to locate you, their orbital period would be about 90 minutes, and they're at a lower altitude. The geostationary satellites are way out there - their period is 24 hours, effectively placing them continuously over a point on the Earth. From there they can see quite a lot continually, but you would require a stronger transmitter to reach them.