Evaluation of the performance of GNSS-based velocity estimation algorithms

Global Navigation Satellite System(GNSS)based velocity estimation is one of the most cost-effective and widely used methods in determining velocity in geodesy and transport applications.Highly accurate and reliable velocity measurements can be obtained by exploiting the raw Doppler,carrier phase,and pseudorange measurements with a GNSS receiver.There are several approaches to GNSS-based velocity determination.This paper investigates the characteristics of the approaches which are currently popular and applicable to the observations of Global Positioning System(GPS),BeiDou Navigation Satellite System(BDS),and their combination(GPS/BDS).Specifically,it evaluates the performance of the velocity estimated based on the Raw Doppler method,the Time-Differenced Pseudorange method,the Time-Differenced Carrier Phase method,and the Double-Differenced Carrier Phase method,in both static and dynamic modes and in open and urban scenarios.The experiments show that BDS has the advantages in delivering accurate velocity determinations over GPS in the Asia–Pacific region,and the effectiveness of the GPS/BDS in improving the overall accuracy of velocity determination in complex urban scenarios.