Patent ID: 8373592
Filing Date: 2013-02-12
Classification: G01S

Abstract:
1. A method for determining an initial position by a processor for calculating a position of a receiver which receives signals from a plurality of satellites, the method comprising: a) determining a first satellite based on the signals at the receiver; b) determining a plurality of candidate points based on an erroneous position at the receiver; c) determining a selected candidate point from the plurality of candidate points at the receiver; d) calculating a first difference between a first measured range and a first calculated range corresponding to the first satellite at the receiver; e) calculating second differences between a second measured range and a second calculated range corresponding to satellites other than the first satellite at the receiver; f) producing a value indicating validity of the selected candidate point using the first difference and the second differences at the receiver; g) repeating steps c) through f) to produce the value indicating validity of each of the plurality of candidate points at the receiver; h) selecting at least one reliable point from the plurality of candidate points using the value indicating validity of each of the candidate point to execute position converging calculation at the receiver; and i) determining the initial position based on the at least one reliable point at the receiver, wherein the step f) includes calculating the value indicating validity of the selected candidate point by accumulating a subtraction result between the first difference and the second differences.