An Effective GNSS/PDR Fusion Positioning Algorithm on Smartphones for Challenging Scenarios

Abstract

The location-based smartphone service brings new development opportunities for seamless indoor/outdoor positioning. However, in complex scenarios such as cities, tunnels, overpasses, forests, etc., using only GNSS on smartphones cannot provide stable and reliable positioning results. Usually, additional sensors are needed to assist GNSS. This paper investigates the GNSS positioning algorithm assisted by pedestrian dead reckoning (PDR) in complex scenarios. First, we introduce a step detection algorithm based on the peak–valley of acceleration modulus, and the Weinberg model and the Mahony algorithm in PDR are used to estimate step length and heading. On this basis, we evaluated the performance of GNSS/PDR fusion positioning in an open scenario, a semiopen scenario, and a blocked scenario, respectively. Finally, we develop a GNSS/PDR real-time positioning software, called China University of Mining and Technology-POSitioning (CUMT-POS) version 1.0, on the Android 10 platform. By comparing GNSS solutions, PDR solutions, GNSS/PDR solutions, and real-time kinematic (RTK) solutions, we verify the potential auxiliary ability of PDR for GNSS positioning in complex environments, proving that multisource sensor fusion positioning significantly improves reliability and stability. Our research can help the realization of urban informatization and smart cities.

Relative Localization and Circumnavigation of a UGV0 Based on Mixed Measurements of Multi-UAVs by Employing Intelligent Sensors

“…q i (k) is expressed as an estimate of q i (k). Note that u i (k) should also satisfy u i (k) ≤ U to address the circumnavigation problem (13), where U is the maximum velocity.…”

“…The most common methods include external positioning systems, such as the Global Positioning System (GPS) [9,10] and anchor-based ultra-wideband (UWB) positioning [11,12], which have notably enhanced positioning accuracies. However, in specific environments, such as urban canyons, indoors, or during severe weather conditions, satellite signals may be obstructed or interfered with, thereby limiting the reliability and accuracy of traditional Global Navigation Satellite Systems (GNSSs) [13,14] in these situations. Furthermore, the deployment of an external positioning system can lead to complexities in maintenance and updating.…”