Walking Gait Assisted Vector Tracking GNSS for Pedestrian Position

Vector tracking (VT) is reported as a promising method to enhance Global Navigation Satellite System (GNSS) position accuracy in urban areas. Direct signal-tracking parameters and navigation solution estimation fully exploit the inherent relationship between the navigation solutions and signal-tracking parameters, which bring advantages in improving GNSS performance under signal-challenging environments, i.e., weak signals. In this article, we first investigated VT-based pedestrian position, and we proposed walking gaits-aided VT (WG-VT) method for pedestrian navigation in urban areas. Specifically, measurements from smartphone accelerometers are employed to detect step, and the estimated step length and detected zero velocity are utilized as the constraints in an increment optimization method to improve the VT position accuracy. Field tests are carried out to assess the WG-VT for pedestrian navigation in urban areas. Results show that the horizontal position errors are improved compared with the VT without aiding.