A Solution Separation Algorithm for Velocity Estimation in Rail and Road Applications

In this work, we propose the use of velocity directly derived from Global Navigation Satellite System observables in safety-critical applications. In particular, we extend the Solution Separation method originally introduced for positioning to velocity estimated starting from carrier phases. Exploiting carrier phases temporal differences as done here removes the need for ambiguity fixing, but the hazards caused by cycle slips remain. Therefore, specific barriers (cycle slip detectors) and robust methods like Solution Separation one, providing also confidence Interval / Protection Levels have to be adopted. Experimental results show that the proposed method can achieve performance comparable with those exhibited by Real Time Kinematic and Precise Point Positioning based solutions, without the need of fixing phase ambiguities. Thus it is faster, less computationally complex, and less expensive than them.