Enhancement of Multi-Constellation Satellite-Based Precise Positioning and Ionospheric Remote Sensing

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The proposed research will involve three themes: 1) improvement of positioning and navigation using multiple global navigation satellite systems (GNSS); 2) improvement of inexpensive, primarily single-frequency, GNSS positioning and navigation; and 3) remote sensing of the ionosphere using GNSS techniques, using primarily data from my instrument on the Canadian CASSIOPE research satellite. Multi-System, Multi-Frequency GNSS Positioning: Although GPS was the first widely available satellite navigation system, it has now been joined by the Russian GLONASS system, the European Galileo system, and the Chinese BeiDou system-all of which have partially completed orbiting constellations of satellites, which will be become fully operational by 2020 or so. The new GNSS along with modernized GPS will offer new signal structures on multiple frequencies that will greatly benefit positioning and navigation. By using observations from all available satellites, regardless of constellation, we have the possibility of significantly improving navigation availability and continuity in restricted environments where signals from some directions might be blocked. We also have the potential for improved positioning accuracy due to more observations with more favourable geometry being available. Our precise point positioning algorithms and software already produce positions and trajectories with reasonable precision and accuracy but work needs to done to improve their capabilities and thus demonstrate how best to handle multi-system and multi-frequency data for optimum results. Improvement of Low-Cost GNSS Positioning: While positioning and navigation to about the one-to-two-metre accuracy level is currently possible with conventional single-frequency, code-based GPS measurements, higher accuracies can be achieved by additionally using carrier-phase observations and by using signals from additional constellations such as GLONASS. And for navigation, where not just the accuracy of the system is important but also its availability, continuity, and integrity, there is significant benefit from multi-constellation observations supplemented by additional sensors such as inertial measurement units. Nowhere is this more needed than for automotive applications in urban environments. We will develop novel approaches to low-cost, supplemented GNSS positioning to achieve the required accuracy and reliability of systems being demanded by the automotive positioning industry. Ionosphere Remote Sensing: Our work will also involve investigating GNSS receiver performance in disturbed ionospheric conditions as well as using GNSS as a remote-sensing tool for studying the morphology of the ionosphere's electron distribution. All of our proposed GNSS research will be of significant benefit for positioning and navigation not only in Canada but worldwide.