{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:38:33Z","timestamp":1760243913479,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2010,5,10]],"date-time":"2010-05-10T00:00:00Z","timestamp":1273449600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The detection of low received power of global positioning system (GPS) signals in the signal acquisition process is an important issue for GPS applications. Improving the miss-detection problem of low received power signal is crucial, especially for urban or indoor environments. This paper proposes a signal existence verification (SEV) process to detect and subsequently verify low received power GPS signals. The SEV process is based on the time-frequency representation of GPS signal, and it can capture the characteristic of GPS signal in the time-frequency plane to enhance the GPS signal acquisition performance. Several simulations and experiments are conducted to show the effectiveness of the proposed method for low received power signal detection. The contribution of this work is that the SEV process is an additional scheme to assist the GPS signal acquisition process in low received power signal detection, without changing the original signal acquisition or tracking algorithms.<\/jats:p>","DOI":"10.3390\/s100504717","type":"journal-article","created":{"date-parts":[[2010,5,10]],"date-time":"2010-05-10T11:16:36Z","timestamp":1273490196000},"page":"4717-4738","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Signal Existence Verification (SEV) for GPS Low Received Power Signal Detection Using the Time-Frequency Approach"],"prefix":"10.3390","volume":"10","author":[{"given":"Shau-Shiun","family":"Jan","sequence":"first","affiliation":[{"name":"Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan 70101, Taiwan"}]},{"given":"Chih-Cheng","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan 70101, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2010,5,10]]},"reference":[{"key":"ref_1","unstructured":"Misra, P., and Enge, P. (2006). Global Positioning System: Signals, Measurements and Performance, Ganga-Jamuna Press. [2nd ed.]."},{"key":"ref_2","unstructured":"Kaplan, E.D., and Hegarty, C. (2005). Understanding GPS: Principles and Applications, Artech House. [2nd ed.]."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Tsui, J.B.Y. (2004). Fundamentals of Global Positioning System Receivers: A Software Approach, John Wiley & Sons. [2nd ed.].","DOI":"10.1002\/0471712582"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1109\/5.736341","article-title":"GPS receiver architectures and measurements","volume":"87","author":"Braasch","year":"1999","journal-title":"Proc. IEEE"},{"key":"ref_5","unstructured":"Lin, M., and Tsui, J.B.Y. Comparison of Acquisition Methods for Software GPS Receiver. Salt Lake City, UT, USA."},{"key":"ref_6","unstructured":"Psiaki, M.L. Block Acquisition of Weak GPS Signals in a Software Receiver. Salt Lake City, UT, USA."},{"key":"ref_7","unstructured":"Carmona, R., Hwang, W.L., and Torresani, B. (1998). Practical Time-Frequency Analysis: Gabor & Wavelet Transforms with an Implementation in S (Wavelet Analysis and Its Applications, Vol 9), Academic Press."},{"key":"ref_8","first-page":"229","article-title":"The Weighted Coherent Overlapping Tracking Method for GPS Receivers","volume":"30","author":"Jan","year":"2009","journal-title":"J. Chin. Soc. Mech. Eng"},{"key":"ref_9","first-page":"83","article-title":"A Study on the Application of the Empirical Mode Decomposition to GPS Signal Acquisition Process","volume":"41","author":"Sun","year":"2009","journal-title":"J. Aero. Astro. Aviation"},{"key":"ref_10","unstructured":"Sun, C.C., and Jan, S.S. Time-Frequency Analyses of Global Navigation Satellite System Signals. Savannah, GA, USA."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1109\/JSYST.2007.914914","article-title":"Time-Frequency Excision for GNSS Applications","volume":"2","author":"Borio","year":"2008","journal-title":"IEEE Syst. J"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1248","DOI":"10.3390\/a2031248","article-title":"RFI Mitigation in Microwave Radiometry Using Wavelets","volume":"2","author":"Camps","year":"2009","journal-title":"Algorithms"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1017\/S0373463307004146","article-title":"Single Frequency Multipath Mitigation Based on Wavelet Analysis","volume":"60","author":"Aram","year":"2007","journal-title":"J. Navig"},{"key":"ref_14","first-page":"41","article-title":"Application of 3D time-frequency analysis in monitoring full-scale structural response","volume":"8","author":"Li","year":"2007","journal-title":"J. Geospat. Eng"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1006\/jsvi.2001.4087","article-title":"Time-frequency analysis of a suspension bridge based on GPS","volume":"254","author":"Xu","year":"2002","journal-title":"J. Sound Vib"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"903","DOI":"10.1098\/rspa.1998.0193","article-title":"The Empirical Mode Decomposition and the Hilbert Spectrum for Nonlinear and Nonstationary Time Series Analysis","volume":"454","author":"Huang","year":"1998","journal-title":"Proc. R. Soc. Lond. A"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1146\/annurev.fl.24.010192.002143","article-title":"Wavelet Transforms and Their Applications to Turbulence","volume":"24","author":"Farge","year":"1992","journal-title":"Annu. Rev. Fluid Mech"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Boashash, B. (1992). Time-Frequnecy Signal Analysis, Methods and Applications, Longman.","DOI":"10.2307\/2532288"},{"key":"ref_19","unstructured":"Jeng, Y.N., Huang, J.M., and Tsai, J.L. (2006, January November). New Time-Frequency Analysis of Acoustic Data. Tainan, Taiwan."},{"key":"ref_20","unstructured":"Jeng, Y.N., and Cheng, Y.C. (2007, January April). Fourier Sine\/Cosine Spectrums and Errors of Derivatives Estimated by Spectrums. Chania, Greece."},{"key":"ref_21","unstructured":"Hahn, S.L. (1996). Hilbert transforms in signal processing, Artech House."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Jeng, Y.N., and Chen, J.C.T. (2006, January June). Some Detailed Information of a Low Speed Turbulent Flow over a Bluff Body Evaluated by New Time-Frequency Analysis. San Francisco, CA, USA.","DOI":"10.2514\/6.2006-3340"},{"key":"ref_23","unstructured":"Parkinsion, B.W., and Spilker, J.J. (1996). Global Positioning System: Theory & Applications (Volume One and Two), American Institute of Aeronautics & Astronautics."},{"key":"ref_24","unstructured":"Akos, D.M. (A Software Radio Approach to Global Navigation Satellite System Receiver Design, 1997). A Software Radio Approach to Global Navigation Satellite System Receiver Design, PhD dissertation,."},{"key":"ref_25","unstructured":"Oppenheim, A.V., Sch\u00e4fer, R.W., and Buck, J.R. (1999). Discrete-Time Signal Processing, Prentice-Hall. [2nd ed.]."},{"key":"ref_26","unstructured":"Gao, G.X. DME\/TACAN Interference and its Mitigation in L5\/E5 Bands. Fort Worth, TX, USA."},{"key":"ref_27","unstructured":"Borre, K., Akos, D.M., Bertelsen, N., Rinder, P., and Jensen, S.H. (2007). A Software-Defined GPS and Galileo Receiver: A Single-Frequency Approach, Springer Verlag."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/5\/4717\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:02:23Z","timestamp":1760220143000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/5\/4717"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,5,10]]},"references-count":27,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2010,5]]}},"alternative-id":["s100504717"],"URL":"https:\/\/doi.org\/10.3390\/s100504717","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2010,5,10]]}}}