High Latitude Ionospheric Scintillation: Detection and Isolation From Oscillator Phase Noise as Applied to GNSS.

摘要

This thesis investigates the detection of high latitude ionospheric scintillation effects using data collected by the author during two field exercises into the Canadian low arctic and high arctic regions during March and October--November 2008 respectively. The effect of ionospheric phase scintillation in these regions is studied through the observation of the influence it has on both the L1CA and L2C modernized GPS signals simultaneously. A pulsation detection method is proposed and investigated which identifies, and in turn exploits an apparent high level of correlation between the phase effects present on the L1 and L2 GPS carriers during low arctic pulsation events. Using this data, the level of correlated activity between the civil GPS signals during both polar and auroral scintillation events is related to the physical scale sizes of detectable ionospheric features. As a further novel contribution the presentation of a method for estimating the epoch to epoch phase change in the local oscillator over millisecond time scales is presented. This method is potentially capable of providing apparent phase stability commensurate with the use of an ovenized quartz oscillator within equipment actually utilizing an inexpensive (e.g. TCXO) oscillator, thereby allowing phase scintillation detection while using very low cost user equipment. An appendix detailing the design and development of a multi channel multi GNSS wide bandwidth research front-end for use in future investigations is included.