Application of Elevation Based Multipath Correction Model in BDS Relative Positioning

   The accuracy of pseudorange observation has a great impact on the rate of relative positioning solution convergence.Related research found the exist of multipath deviation in the BDS pseudorange observation,which is associated with evelation angle and severely reduces the pseudorange observation precision.By the EMD filter and polynomial fitting we established a multipath correction model based on elevation angle to eliminate this kind of error.Experimental results show that the multipath correction model based on elevation angle can effectively improve the accuracy of pseudorange observation, and speed up the rate of relative positioning results convergence.After correction the precision of four times 2 h positioning results increased by 64.1％, 43.9％, 35.3％ and 43.9％ respectively.