Patent ID: 8265125
Filing Date: 2012-09-11
Classification: G01S,H04B

Abstract:
1. A code phase error estimating method, comprising: calculating correlation for I and Q components of a reception signal of a spread modulated positioning signal, and a replica signal of a spread code; judging code phase based on the result of the correlation calculation; calculating a ratio of a first difference to a second difference, the first difference being a first correlation value minus a third correlation value, the second difference being a second correlation value minus the third correlation value, the first correlation value being a correlation value at the code phase, the second correlation value being a correlation value at a phase shifted from the code phase by X chip (0<X<1), and the third correlation value being a correlation value at a phase shifted from the code phase by Y chips (1<Y); and estimating the code phase error by using the ratio and an offset value of the ratio determined in advance for the spread code when the reception signal is a multipath signal.