Patent ID: 7619559
Filing Date: 2009-11-17
Classification: G01S

Abstract:
1. A method for rapidly acquiring and using a plurality of satellite ranging signals to determine position information, the method comprising: using a first user receiver to receive information from a remote source and satellite ranging signals from satellites within view of said first user receiver, to determine a probable location of the first user receiver; transmitting from the first user receiver, the probable location of the first user receiver and the information to a second user receiver; using the information and the first user receiver probable location to limit an Earth-reference search space region associated with the second user receiver to predetermined geographic dimensions; using the second user receiver to simultaneously obtain a plurality of satellite ranging signals from each one of a plurality of said satellites within view of said second user receiver; and causing the second user receiver to use the obtained satellite ranging signals and the probable location of the first user receiver to rapidly obtain a probable geographic location of the second user receiver by coherently combining the power in the received satellite ranging codes received from said plurality of satellites at a plurality of grid points within said search space region.