Abstract: A method and apparatus for determining attitude information using a down conversion reference and a carrier phase and code phase generator. The apparatus uses individual phase registers for signal received from each antenna to solve the phase difference concurrently. The invention also discloses an attitude sensing method where only one receiving antenna is required. A method and structure for using variable correlation width is also disclosed to optimize noise cancellation under different noise environment.

Abstract: A method is provided for processing position and travel related information through a data processing station on a data network. In one embodiment, a GPS receiver is used to obtain a measured position fix of a mobile unit. The measured position fix is reported to the data processing station which associates the reported position to a map of the area. Typically, the measured position of the mobile unit is marked and identified by a marker on the map. The area map is then stored in the data processing station and made available for access by authorized monitor units or mobile units. An authorized monitor unit may request for a specific area map by sending a request through the data network. Upon receiving a request, the data processing unit sends the area map to the monitor unit. Data processing station may also perform a database search for travel-related information, such as directions to a gasoline station.