Patent ID: 8629801
Filing Date: 2014-01-14
Classification: G01S

Abstract:
1. A method of determining a location of an event of interest by processing signals from a satellite positioning system, the method comprising: periodically recording, in a storage-device, blocks of data samples of a satellite broadcast, wherein said blocks of data samples are generated by an RF front end of a portable battery-operated device; in response to a request for a position determination at a particular time, processing, using a processor, a most recent block of data samples in an attempt to obtain a position fix, wherein if the attempt to obtain a position fix is unsuccessful, the method further comprises processing, using the processor, blocks of data samples which were recorded further back in time in a sequence to make further attempts to obtain a position fix, until a position fix is obtained successfully, wherein the blocks of data samples used for the further attempts relate to time instants which are irregularly spaced before the particular time.