Cold-Warm-Hot GPS Start

TTFF is a measure of the time required for a GPS receiver to acquire satellite signals and navigation data, and calculate a position solution (called a fix).The above happens during a cold start, this is when the GPS module has been off for some time and has no data in its memory. A full Almanac download is required to get TTFF. If the GPS module has clear line of sight to all satellites, the shortest time for TTFF is 12.5 minutes.In a warm start scenario,  the GPS module has valid Almanac data,  is close to its last position (100km or so) and knows the time  within about 20 seconds. This approximate information helps the receiver estimate the range to satellites.  The TTFF for a warm start can be as short as 30 seconds, but is usually just a couple of minutes.A receiver that has a current almanac, ephemeris data, time and position can have a hot start. A hot start can take from 0.5 to 20 seconds for TTFF.

Always turn your tracker on at the target location and verify on your cell phone. This allows a warm and hot start when the vehicle moves!

Tracking Tips