Statistical Approach to Mitigating 3G Interference to GPS in 3G Handset

Taher AlSharabati, Yinchao Chen
DOI: 10.4236/ijcns.2010.39097                

Abstract

In this paper, we show how statistical decision theory can be used to solve real life product problems. Global Positioning System (GPS) Performance in a mobile handset is degraded whenever it is simultaneously used with a 3G data or voice call. This degradation is due to the 3G transmitter interference. Mitigation methods to interference in GPS have been pro-posed. However, most of these methods depend on hardware and signal processing or just hardware solutions. In some cases, it maybe difficult to implement these hardware methods, especially, in mobile handsets due to the small size of the handset, printed circuit board (PCB) layout issues and the added cost. In this paper, a novel signal processing statistical algorithm approach is proposed to mitigate the 3G interference to GPS. This statistical approach utilizes the knowledge of the statistical characteristics and distributions of both, the GPS signal and noise. Then the method utilizes the probabilities to make a statistical decision to remove the effect of noise. This method does not require room on the PCB of the mobile handset and therefore no layout challenges arise. In addition, cost is minimized and the product turn in cycle is shortened. This paper offers theoretical as well as practical insight to the GPS operation during 3G call inside the mobile phone.

Keywords

Detection and Estimation, Global Positioning System (GPS), Satellite Acquisition, Wide Band Code Division Multiple Access (WCDMA)

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	T. Sharabati and Y. Chen, “Mitigating 3G Carrier Inter- ference to GPS Due to Co-existence in 3G Handset,” IEEE NAECON, 2009, pp. 86-91.
[2]	T. Sharabati, “Proposal for Mitigating 3G Interferrence to GPS,” University of South Carolina, South Carolina, 2009.
[3]	K. Borre, D. M. Akos, N. Bertelsen, P. Rinder and S. H. Jensen, “A Software Defined GPS and Galileo Receiver Birkhauser,” Birkhauser, Boston, 2007.
[4]	W. Betz John and R. Kolodziejski Kevin, “Extended Theory of Early-Late Code Tracking for A Band limited GPS Receiver,” Navigation, Journal of the Institute of Navigation, Vol. 47, No. 3, 2000, pp. 211-226.
[5]	W. Betz John, “Effect of Narrowband Interference on GPS Code Tracking Accuracy,” ION NTM, 26-28 January 2000, pp. 16-27.
[6]	B. Michael and A. J. Van Dierendonck, “GPS Receiver Architecture and Measurements,” Proceedins of the IEEE, Vol. 87, No. 1, 1999, pp. 48-64.
[7]	P. Ward, “Interference Heads Up,” GPS World, Vol. 19, No. 6, June 2008, pp. 64-73.
[8]	S. Semiconductor, “SE4120L GNSS Receiver IC”, June 2008.
[9]	A. Technologies, “UTMS1700/2100(1710-1755MHz) and UMTS1700 (1750-1785MHz),” Avago Technologies, AV02- 1907EN, 2009.
[10]	W. Couch Leon II, “Digital and Analog Communication Systems,” 3rd edition, Collier Macmillan, New York, 1990.