Abstract: A method for adjusting packet length is disclosed. A first reference point currently closest to the mobile device is calculated. It is determined whether the mobile device has been updated a reference point from a server after activated. It is determined whether the cycle of updating position information has been expired if the mobile device has been updated a first reference point from the server after activated. If the cycle of updating position information has not been expired, a position as the mobile device initially enter a range of the previous reference point at an initial time and then moves to a range of the current reference point at the current time is calculated to estimate a future position of the mobile device. A future reference point of the mobile device is calculated according to the estimated future position and is updated to the mobile device and the server.

Abstract: A method for adjusting packet length is disclosed. A first reference point currently closest to the mobile device is calculated. A current position of a mobile device is compared with GPS data of the first reference point to calculate brief GPS data. It is determined whether a second reference point has been uploaded to the server. It is determined whether the first reference point is identical to the second reference point if the second reference point has been uploaded to the server. The first reference point is uploaded to the server if the first reference point is not identical to the second reference point. The first reference point is uploaded to the server if the second reference point has not been uploaded to the server, and the brief GPS data is uploaded to the server.

Abstract: A method for adjusting packet length is disclosed. A first reference point currently closest to the mobile device is calculated. It is determined whether the mobile device has been updated a reference point from a server after activated. It is determined whether the cycle of updating position information has been expired if the mobile device has been updated a first reference point from the server after activated. If the cycle of updating position information has not been expired, a position as the mobile device initially enter a range of the previous reference point at an initial time and then moves to a range of the current reference point at the current time is calculated to estimate a future position of the mobile device. A future reference point of the mobile device is calculated according to the estimated future position and is updated to the mobile device and the server.

Abstract: A method for adjusting packet length is disclosed. A first reference point currently closest to the mobile device is calculated. A current position of a mobile device is compared with GPS data of the first reference point to calculate brief GPS data. It is determined whether a second reference point has been uploaded to the server. It is determined whether the first reference point is identical to the second reference point if the second reference point has been uploaded to the server. The first reference point is uploaded to the server if the first reference point is not identical to the second reference point. The first reference point is uploaded to the server if the second reference point has not been uploaded to the server, and the brief GPS data is uploaded to the server.

Abstract: A method for adjusting packet length is disclosed. A first dynamic reference point currently closest to the mobile device is calculated. A current position of a mobile device is compared with GPS data of the first dynamic reference point to calculate brief GPS data. It is determined whether a second dynamic reference point has been uploaded to the server. It is determined whether the first dynamic reference point is identical to the second dynamic reference point if the second dynamic reference point has been uploaded to the server. The first dynamic reference point is uploaded to the server if the first dynamic reference point is not identical to the second dynamic reference point. The first dynamic reference point is uploaded to the server if the second dynamic reference point has not been uploaded to the server, and the brief GPS data is uploaded to the server.

Abstract: A DC/DC converter includes a converting circuit for converting a first voltage into a second voltage; a controller for generating spread spectrum switching signals; and a switch according to the spread spectrum switching signals controlling the on/off state of the switch.

Abstract: A DC/DC converter includes a converting circuit for converting a first voltage into a second voltage; a controller for generating spread spectrum switching signals; and a switch according to the spread spectrum switching signals controlling the on/off state of the switch.