초록 ▼

A method and apparatus for determining and removing the error in the SPS measurement of the Global Positioning System due to ionospheric delay. The disclosed technique utilizes semi-codeless technique to provide high accuracy GPS measurements. The delay of the P code is varied and the signals are cr

A method and apparatus for determining and removing the error in the SPS measurement of the Global Positioning System due to ionospheric delay. The disclosed technique utilizes semi-codeless technique to provide high accuracy GPS measurements. The delay of the P code is varied and the signals are cross correlated until a maximum value is reached. When the cross correlation of the L1 and L2 signals is at a peak value, the relative delay between the L1 and L2 signals is proportional to the ionospheric delay. The derived ionospheric delay may be accounted for in measurement analysis of the L1 signal to provide for a high precision position solution. The semi-codeless correlator also provides the L1-L2 carrier phase measurement for wide-lane applications.

대표청구항 ▼

[ We claim:] [8.] A processor for eliminating ionospheric delay error due to an ionospheric delay from the signals of a global positioning system signal including the L1 and L2 signals without knowledge of the Y code signal due to encryption of the L1 and L2 signals to determine a high precision pos

[ We claim:] [8.] A processor for eliminating ionospheric delay error due to an ionospheric delay from the signals of a global positioning system signal including the L1 and L2 signals without knowledge of the Y code signal due to encryption of the L1 and L2 signals to determine a high precision position solution, the processor comprising:a first precorrelation filter for filtering the encryption code from a signal comprising the L1 signal multiplied with a high precision code, said L1 signal being previously encoded with said high precision code, said first precorrelation filter providing an output;a second precorrelation filter and a high precision code delay unit having a high precision code delayed output; said second precorrelation filter for filtering the encryption code from a signal comprising the L2 signal multiplied with said high precision code delayed output, said second precorrelation filter providing an output;a predetection filter for filtering a signal comprising said output of said first precorrelation filter multiplied with said output of said second precorrelation filter, said predetection filter providing an output;a tracking commands unit receiving said output of said predetection filter for processing tracking commands, said tracking commands unit providing an output to said high precision code delay unit; and a post detection filter receiving said output of said predetection filter for providing an output proportional to the ionospheric delay based upon the cross correlation of the L1 and L2 signals.