UCGE Reports
Number 20268
Department of Geomatics Engineering
GPS L5 Software Receiver Development for HighAccuracy Applications
(URL: http://www.geomatics.ucalgary.ca/research/publications/GradTheses.html)
by Cécile Mongrédien
May 2008
UNIVERSITY OF CALGARY
GPS L5 Software Receiver Development for High-Accuracy Applications
by
Cécile Mongrédien
A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY
DEPARTMENT OF GEOMATICS ENGINEERING CALGARY, ALBERTA MAY, 2008
Cécile Mongrédien 2008
Abstract
The GPS L5 signal, part of the effort to modernize GPS, was designed to increase performance for civilian users. In order to fully exploit the structural innovations brought by this signal, new receiver architectures are needed. This dissertation proposes novel acquisition and tracking algorithms that can maximize the L5 signal performance in terms of acquisition robustness, tracking sensitivity and measurement accuracy.
A cascaded algorithm is shown to enable robust and direct acquisition of the signal. A coarse acquisition step that coherently combines the data and pilot channel is first used to acquire the PRN code delay. An intermediate 1-ms FLL-based tracking is then introduced to remove the residual Doppler error and a pilot-only fine acquisition step is implemented to simultaneously acquire the NH code delay and perform bit synchronization.
Different data- and pilot-only constant bandwidth tracking strategies are investigated to assess their relative performance in terms of sensitivity and accuracy in the presence of white noise, oscillator phase noise and receiver dynamics. Results show that the L5 dataless channel can increase phase and frequency tracking sensitivity by approximately 5 dB in addition to increasing accuracy. The superiority of phase tracking is also demonstrated since, in addition to enabling navigation message decoding, it is also shown to provide greater accuracy and better sensitivity than frequency tracking. Code tracking accuracy is also shown to greatly benefit from the dataless channel through the use of long coherent integration times. Further measurement accuracy can be achieved through

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