This thesis examines the sampling and jitter specifications and considerations for Global Navigation Satellite Systems (GNSS) software receivers. Software Radio (SWR) technologies are being used in the implementation of communication receivers in general and GNSS receivers in particular. With the advent of new GPS signals, and a range of new Galileo and GLONASS signals soon becoming available, GNSS is an application where SWR and software-defined radio (SDR) are likely to have an impact. The sampling process is critical for SWR receivers where it occurs as close to the antenna as possible. One way to achieve this is by BandPass Sampling (BPS), which is an undersampling technique that exploits aliasing to perform downconversion. In this thesis, the allowable sampling frequencies are calculated and analyzed for the multiple frequency BPS software radio GNSS receivers. The SNR degradation due to jitter is calculated and the required jitter standard deviation allowable for wach GNSS band of interest is evaluated and a basic jitter budget is calculated that could assist in the design of multiple frequency SWR GNSS receivers. Analysis shows that psec-level jitter specifications are required in order to keep jitter noise well below the thermal noise for software radio satellite navigation receivers. However, analysis of a BPSK system shows that large errors occur if the jittered sample crosses a data bit boundary. However, the signal processing techniques required to process the BOC modulation are much more challenging than those for traditional BPSK. BOC and AltBOC have more transitions per chip of spreading code and hence jitter creates greater SNR degradation. This work derives expressions for noise due to jitter taking into account the transition probability in QPSK, BOC, AltBOC systems. Both simulations and analysis are used to give a better understanding of jitter effects on Software Radio GNSS receivers.

GPS has become very popular in recent years. It is used in wide range of applications including aircraft navigation, search and rescue, space borne attitude and position determination and cellular network synchronization. Each application places demands on GPS for various levels of accuracy, integrity, system availability and continuity of service. Radio frequency interference (RFI) which results from many sources such as TV/FM harmonics, radar or mobile satellite systems, presents a challenge to the use of GPS. It can affect all the service performance indices mentioned above. To improve the accuracy of GPS positioning, a continuously operating reference station (CORS) network can be used. A CORS network provides all the enabled GPS users in an area with corrections to the fundamental measurements, producing more precise positioning. A threat to these networks is a threat to all high-accuracy GPS users. It is therefore necessary to monitor the quality of the received signal with the objective of promptly detecting the presence of RFI and providing a timely warning of the degradation of system accuracy, thereby boosting the integrity of GPS. This research was focused on four main tasks: a) Detection. The focus here is on a power spectral density fluctuation detection technique, in which statistical inference is used to detect narrowband continuous-wave (CW) interference in the GPS signal band after being captured by the RF front-end. An optimal detector algorithm is proposed. At this optimal point, for a fixed Detection Threshold (DT), probability of false alarm becomes minimal and for a fixed probability of false alarm, we can achieve the minimum value for the detection threshold. Experiments show that at this point we have the minimum computational load. This theoretical result is supported by real experiments. Finally this algorithm is employed to detect a real GPS interference signal generated by a TV transmitter in Sydney. b) Characterization. In the characterization section, using the GNSS signal structure and the baseband signal processing inside the GNSS receiver, a closed formula is derived for the received signal quality in terms of effective carrier to noise ratio ( ). This formula is tested and proved by calculating the C/No using the I and Q data from a software GPS receiver. For pulsed CW, a similar analysis is done to characterize the effect of parameters such as pulse repetition period (PRP) and also duty cycle on the received signal quality. Considering this characterization and the commonality between the GPS C/A code and Galileo signal as a basis to build up a common term for satellite availability, the probability of satellite availability in the presence of CW interference is defined and for the two currently available satellite navigation systems (GPS L1 signal and Galileo signal (GIOVE-A BOC(1, 1) in the E1/L1 band)) it is shown that they can be considered as alternatives to each other in the presence of different RFI frequencies as their availability in the presence of CW RFI is different in terms of RFI frequency. c) Mitigation. The last section of the research presents a new concept of ?Satellite Exclusion Zone?. In this technique, using our previously developed characterization techniques, and considering the fact that RFI has different effects on different satellite signals at different times depending on satellite Doppler frequency, the idea of excluding the most vulnerable satellite signal from positioning calculations is proposed. Using real data and real interference, the effectiveness of this technique is proven and its performance analyzed. d) Hardware implementation. The above detection technique is implemented using the UNSW FPGA receiver board called NAMURU.

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 206-216).

Thesis (M.S.)--Ohio University, June, 2001. / Title from PDF t.p.

Thesis (M.S.)--Ohio University, June, 2000. / Title from PDF t.p.

Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisors: Chandra Kambhamettu, Dept. of Computer & Information Sciences; and Cathleen A. Geiger, Dept. of Geography. Includes bibliographical references.

Thesis (Ph.D.)--University of Melbourne, Dept. of Geomatics, 2009. / Typescript. Includes bibliographical references (leaves 193-204)

Thesis (M.App.Sc.) - Carleton University, 2005. / Includes bibliographical references (p.120-125 ). Also available in electronic format on the Internet.

Thesis (M.Sc. (Physics & Electronics)) - Rhodes University, 2008. / A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science.

Thesis (M.S.)--California Polytechnic State University, 2009. / Title from PDF title page; viewed on June 18, 2009. Major professor: Hugh Smith, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Computer Science." "June 2009." Includes bibliographical references (p. 55-56). Also available on microfiche.