Abstract: A method of dynamically optimizing the update rate of GPS output data has acts of setting relationships between different moving speeds and different update rates; sensing a current moving speed of a GPS receiver; determining a update rate corresponding to the current moving speed of the GPS receiver; and outputting GPS position and velocity data according to the determined update rate. Since the update rate is variable in view of moving speed, a moving map showing GPS information remains a smooth display.

Abstract: A global positioning system (GPS) receiver with extended 1-second hot start capability has an RF chip, a baseband chip, a battery and a LDO regulator. When the GPS receiver is turned on, a main supply voltage charges the battery to store backup power. Once the main supply voltage is turned off, the baseband starts a countdown period. During the countdown period, critical portion of the RF chip, the baseband chip and the regulator use the backup power to continue keeping time. If the GPS receiver is restarted during the countdown period, the GPS receiver has retained information to allow 1-second hot start and the GPS receiver generates position fix instantaneously.