Recent Advances in PNT Technology with GNSS as the Core and Its Application in Emerging Fields

Dear Colleagues,

With the construction and development of BeiDou and Galileo systems, GNSS technology, as the core technology of achieving positioning, navigation, and timing (PNT), has developed rapidly. In order to achieve GNSS precise positioning, there are currently two implementation routes: observation space representation (OSR) and state space representation (SSR). OSR is using observations of a reference station directly or the derived distance-related corrections to eliminate user observation errors based on the high correlation of adjacent GNSS station's observations, while SSR is using actual state-space data, i.e., improved ephemeris (orbit and clock, satellite biases), ionospheric and tropospheric models, etc. to represent the complete GNSS state. The typical OSR technology is real-time kinematic (RTK) relying on double-differenced (DD) ambiguity resolution. The typical SSR technology is precise point positioning (PPP) /PPP-RTK by processing undifferenced (UD) pseudorange and carrier-phase observations from a stand-alone GNSS receiver together with SSR precise ephemeris. Recently, low earth orbit (LEO) enhanced GNSS positioning technology has become an effective means to obtain instant precise positioning. The improvement of application requirements and technological progress directly promotes the application of GNSS high-precision positioning technology from the traditional field to the mass field. Different from traditional GNSS high-precision applications, e.g., surveying and mapping, and GNSS emerging applications, e.g., autonomous driving and drones, have significant application characteristics, including a massive number of users, global wide-area instantaneous positioning, safety-critical operation, location privacy protection, etc.

This Topic is devoted to new advances and research results on GNSS and its application in emerging fields. This Topic includes but is not limited to: GNSS high-precision positioning theories; GNSS precise orbit determination and real-time precise clock estimation; GNSS ionosphere and troposphere modeling; GNSS augmentation messages credible monitoring and assessment; Credible PNT; GNSS+LEO augmentation; GNSS RTK, PPP, PPP-RTK; Multi-sensor fusion; GNSS autonomous driving application.

Prof. Dr. Liang Chen
Dr. Zhiguo Deng
Prof. Dr. Guanwen Huang
Prof. Dr. Huizhong Zhu
Topic Editors