Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article A Reconfigurable GNSS Acquisition Scheme for Time-Frequency Applications | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2008 Article ID 356267 8 pages doi 2008 356267 Research Article A Reconfigurable GNSS Acquisition Scheme for Time-Frequency Applications Daniele Borio1 and Letizia Lo Presti2 1 Department of Geomatics Engineering University of Calgary 2500 University Dr. NW Calgary AB Canada T2N1N4 2 Dipartimento di Elettronica Politecnico di Torino Corso Duca degli Abruzzi 24 10129 Torino Italy Correspondence should be addressed to Daniele Borio Received 11 November 2007 Accepted 11 June 2008 Recommended by Sven Erik Nordholm The extreme weakness of global navigation satellite system GNSS signals makes them vulnerable to almost every kind of interferences that without adequate countermeasures can heavily compromise the receiver performance. An effective solution is represented by time-frequency TF analysis that has proved to be able to detect and suppress a wide class of disturbing signals. However high computational requirements have limited the diffusion of such techniques for GNSS applications. In this paper we propose an effective solution for the efficient implementation of TF techniques on GNSS receivers. The solution is based on the key observation that the first block of a GNSS receiver the acquisition stage implicitly performs a sort of TF analysis. Thus a slight modification in the traditional acquisition scheme enables the fast and efficient implementation of TF techniques for interference detection. The proposed method is suitable for different types of acquisition scheme and its effectiveness is proved by simulations and examples on real data. Copyright 2008 D. Borio and L. Lo Presti. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION In the last few years global navigation .
