Dr. Sunil Bisnath is a Full Professor in the Department of Earth and Space Science and Engineering at York University in Toronto, Canada.  

On the morning of November 18, 2019, at the invitation of Professor Geng Jianghui, Professor Sunil Bisnath made an academic report entitled "GNSS PPP performance using mass market hardware" for teachers and students of our center in the conference room on the 13th floor. Prof. Geng Jianghui, Prof. Ye Shirong, Prof. Nie guigen, Prof. Fang Rongxin and relevant postgraduates attended the symposium.

Professor Sunil Bisnath introduced the advantages of PPP and low-cost receiver (board, chip, antenna and other modules), focused on analyzing the signal strength and signal quality of low-cost hardware, including swiftNav Piksi, μ-blox, smartphone, etc., and showed the convergence time and determination in a variety of experimental scenarios such as static open sky environment, vehicle dynamic urban environment and so on. Professor Sunil Bisnath also pointed out the next research work and future research direction.

The teachers and students at the meeting asked questions and discussed with Professor Sunil Bisnath about their concerns. The new, detailed and interesting report ended with warm applause from teachers and students. 

Abstract of this report:

The next generation of low-cost, multi-frequency, multi-constellation GNSS receivers, boards, chips and antennas are now quickly entering the market.  The presented work provides an investigation into the potential for mass-market, high-accuracy positioning.  A set of experiments have been carried-out, collecting measurements from a number of low-cost, dual-frequency, multi-constellation GNSS boards, chips and antennas.  In order to be comprehensive and realistic, these static and kinematic experiments were conducted in benign, typical, suburban and urban environments.

The Precise Point Positioning (PPP) GNSS measurement processing mode has been used for measurement processing.  While real-time kinematic (RTK) and network RTK dominate urban and suburban markets, it was deemed of great scientific interest to assess the PPP performance with these hardware options with and without additional local augmentation corrections.

Analysis of the raw measurements illustrates a) some significant measurement gaps with some sensors, b) the lower signal availability and c) the weaker signal strength from the chip/antenna combinations as compared to geodetic quality instrumentation, d) high pseudorange multipath and noise, and e) some interesting measurement curiosities.  Results for new smartphone sensors show positioning performance is typically at the few dm-level with limited convergence period – 1 to 2 orders of magnitude better than standard point positioning.  The GNSS chips and boards combined with higher-quality antennas produce positioning performance approaching geodetic quality.  And under ideal conditions, phase ambiguities are resolvable.  However, there are a number of caveats to these performance assessments, as consistence of results is lower for all of these new sensors as compared to geodetic hardware.

These results are very promising for the use of PPP and RTK in next-generation GNSS sensors for smartphone, vehicle, Internet of things (IoT), etc. applications.  Future work includes further tuning of the measurement processing, ambiguity resolution, and use of AI techniques for measurement filtering. 

(Some photos are as follows)