Can the Iridium phone interfere with GPS?
The L band used by Iridium is 45 Mhz above the L band used by GPS. GPS receivers have a filter to reduce interference from nearby frequencies. There has been no measured effect upon GPS receiver accuracy or performance when the phone has been in use. However, FAA regulations regarding portable devices require that the pilot determine that any portable device does not interfere with nav, comm, autopilots, etc. As a good operating practice, the phone should not be used during instrument approaches.
