Portable navigation device with integrated GPS and dead reckoning capabilities

A method for navigation using a portable navigation device equipped with a GPS receiver and a dead reckoning positioning functionality, the method comprising the steps of:

• determining a current position of the portable navigation device using the GPS receiver
• calculating a route through a network of thoroughfares represented by a set of data;
• if the determination of the current position as determined by the GPS receiver is at least partially degraded, determining the current position of the device using the dead reckoning positioning functionality so as to continue calculating the route;
• if the determination of the current position as determined by the GPS receiver is substantially accurate, calibrating the dead reckoning functionality using the GPS receiver;
• and
• if the determination of the current position as determined by the dead reckoning functionality is substantially accurate, calibrating the GPS receiver using the dead reckoning functionality.

A portable electronic device, comprising:

• a memory to store navigation related data, the navigation related data including data indicative of thoroughfares;
• a GPS receiver for determining a current position of the electronic device;
• a dead reckoning component;
• a processor adapted to communicate with the memory, GPS receiver, and dead reckoning component, wherein the processor is operable to calculate a route through the thoroughfares and is further operable to calibrate the GPS receiver using the dead reckoning component;
• and
• a portable housing for storing the GPS receiver, the dead reckoning component, and the processor.

A portable electronic device, comprising:

• a memory adapted to store navigation related data, the navigation related data including data indicative of thoroughfares;
• a GPS receiver for determining a current position of the electronic device;
• a dead reckoning component for determining the current position, such that when the current position as determined by the GPS receiver is partially degraded, the current position as determined by the dead reckoning component may be used to supplement the current position as determined by the GPS receiver;
• a processor adapted to communicate with the memory, GPS receiver, and dead reckoning component and further operable to calibrate the GPS receiver using the current position as determined by the dead reckoning component;
• a display operable to display the current position of the device;
• and
• a portable housing including the memory, the GPS receiver, the dead reckoning component, the processor and the display.