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Signal processing algorithms for FFT-based GNSS receivers

M.Sc. (Tech) Baharak Soltanian’s doctoral dissertation explores alternative signal processing algorithms for positioning devices utilizing Global Navigation Satellite Systems (GNSS).

The main focus is on reducing the implementation complexity of flexible positioning devices with capability to utilize signals from different GNSS systems, like GPS and Galileo. 

Due to the rapid growth of wearable devices and smartphones in recent years, much attention has been directed to designing smaller and more energy efficient GPS receiver chips. Considering the limited source of energy and smaller size of wearable devices, efficient algorithms to reduce the complexity of GNSS chips are in high demand. There is also great interest to utilize jointly different GNSS signals, like the existing US GPS and Russian Glonass systems, as well as emerging European Galileo and Chinese Beidou systems. The utilization of signals from different systems improves the precision and reliability of positioning devices. For multi-standard positioning devices, the so-called software defined radio (SDR) based signal processing architecture gives the needed flexibility. In a GNSS positioning device, the first and most elaborate task is the so-called acquisition stage, which basically refers to the recognition of available satellite signals and coarse synchronization with them. Fast Fourier transform (FFT) based algorithms are commonly considered in SDR based GNSS signal acquisition, but they have relatively high computational complexity, which has hindered their application in consumer devices.

The main objective of M.Sc. (Tech) Baharak Soltanian’s doctoral dissertation is to study and analyze certain important signal processing techniques and to develop reliable algorithms for the acquisition stage in GNSS receivers that can enable low complexity design and practical implementation for FFT-based acquisition. In her dissertation, she proposes novel algorithms for the efficient search of the Doppler frequency shift in the FFT-based acquisition process, which can reduce the complexity of the acquisition stage significantly.  

Overall, the contributions in the area of GNSS receiver signal processing methods enables the design of low cost devices with reduced computational complexity. These contributions are expected to provide useful algorithms for the implementation of flexible, reconfigurable, power/size/cost -efficient multi-standard GNSS receivers.

Public defense of a doctoral dissertation on Friday, 11 September 2015

The doctoral dissertation of M.Sc. Baharak Soltanian in the field of electronics and communications engineering entitled "Signal Processing Algorithms for FFT-based GNSS Receivers" will be publicly examined at the Faculty of Computing and Electrical Engineering of Tampere University of Technology (TUT) in auditorium SJ204, Sähkötalo building (address: Korkeakoulunkatu 1, Tampere, Finland) at 12:00 on Friday, 11 September 2015.

The opponent will be Dr. Harri Saarnisaari from University of Oulu. Professor Markku Renfors from the Department of Electronics and Communications Engineering at TUT will act as the Chairman. 

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News submitted by: Anna Naukkarinen
Keywords: science and research, working at tut