Patent ID: 8912952

Claim:
An ionosphere error estimation method for use in a global positioning system (GPS) device, the GPS device connecting with a first dual-band base station and a second dual-band base station, the ionosphere error estimation method comprising the following steps of: (a) enabling the GPS device to receive a first ionosphere pierce point (IPP) coordinate and a first ionosphere error from the first dual-band base station, wherein the first dual-band base station receives a first positioning signal from a GPS satellite via a first IPP, calculates the first IPP coordinate according to the first IPP and calculates the first ionosphere error according to the first positioning signal; (b) enabling the GPS device to receive a second IPP coordinate and a second ionosphere error from the second dual-band base station, wherein the second dual-band base station receives a second positioning signal from the GPS satellite via a second IPP, calculates the second IPP coordinate according to the second IPP, and calculates the second ionosphere error according to the second positioning signal; (c) enabling the GPS device to receive a user positioning signal from the GPS satellite via a user IPP; (d) enabling the GPS device to calculate a user IPP coordinate according to the user IPP; and (e) enabling the GPS device to calculate a user ionosphere error through interpolation method according to the first IPP coordinate and the first ionosphere error of the first dual-band base station, the second IPP coordinate and the second ionosphere error of the second dual-band base station and the user IPP coordinate directly.