volume | PIER Journals

2009-02-19

A New Proposal Capon Beamformer for Angular Spreads on Distributed Sources in a Cellular Environment

Horacio Monjardin,

Dr. Horacio Monjardin

CICESE Research Center

Mexico

Homepage

David H. Covarrubias-Rosales,

Dr. David H. Covarrubias-Rosales

Electronics and telecommunications

CICESE Research Center

Mexico

Homepage

Ricardo F. Nuñez

Dr. Ricardo F. Nuñez

CICESE Research Center

Mexico

Homepage

Progress In Electromagnetics Research C, Vol. 6, 167-177, 2009

doi:10.2528/PIERC09011607

Abstract

In this work a new robust adaptive digital beamforming algorithm called Gaussian Robust Capon Beamformer (GRCB) is proposed, it is based on conventional Capon criteria and provides compensation of the steering vector errors through diagonal loading approach. This research was conducted assuming a critical scenario where a communication environment presents a high value of angular spread (AS >2 degrees) on signal of interest and in which other beamforming methods, including robust Capon algorithm, can degrade their performance upon presenting the phenomenon of auto-cancellation of the signal of interest. Additionally, is discussed a study of the beamforming algorithms performance, based on Minimum Variance Distortionless Response (MVDR) method as well as its robust version; this study is conducted using a radio channel model with a Gaussian scatters distribution, around the signal of interest and typical angular spread values for different mobile communication environments. Finally, simulations results are shown where the performance of GRCB algorithm is compared with different approaches of Capon beamforming, can be observe that using the proposed algorithm is possible to achieve a minimization in signal of interest degradation and a better isolation, regardless of interferers and noise levels.

Citation

Copy Export

Horacio Monjardin, David H. Covarrubias-Rosales, and Ricardo F. Nuñez, "A New Proposal Capon Beamformer for Angular Spreads on Distributed Sources in a Cellular Environment," Progress In Electromagnetics Research C, Vol. 6, 167-177, 2009.
doi:10.2528/PIERC09011607

References

1. Godara, L., Adaptive Antennas, Chapter 2, CRC Press, 2004.

2. Lorenz, R. G. and S. P. Boyd, "Robust minimum variance beamforming," IEEE Trans. Signal Processing, Vol. 53, No. 5, 1684-1696, 2005.
doi:10.1109/TSP.2005.845436

3. Liberty, J. C. and T. S. Rappaport, Smart Antennas for Wireless Communications: IS-95 and Third Generation CDMA Applications, 215-251, Prentice Hall, 1999.

4. Li, J., P. Stoica, and Z. Wang, "On robust Capon beamforming and diagonal loading," IEEE Transactions on Signal Processing, Vol. 51, No. 7, 1702-1715, 2003.
doi:10.1109/TSP.2003.812831

5. Yi, J., P. Stoica, Z. Wang, and J. Li, Capon Beamforming in the Presence of Steering Vector Errors and Coherent Signals, MIT Lincoln Laboratory, March 11-13, 2003.

6. Janaswamy, R., "Angle and time of arrival statistics for the Gaussian scatter density model," IEEE Transactions on Wireless Communications, Vol. 1, No. 3, 488-497, August 2001.
doi:10.1109/TWC.2002.800547

7. Lopez, C., D. Covarrubias, D. Mu~noz, and M. Panduro, "Statistical cellular Gaussian scatter density channel model employing a directional antenna for mobile environments," AEÄU International Journal of Electronics and Communications, Vol. 59, No. 3, 195-199, June 2005.
doi:10.1016/j.aeue.2004.11.016

8. Haykin, S., Adaptive Filter Theory, Chapter 2, Prentice Hall, 2002.

9. Andrade, A. and D. Covarrubias, "Radio channel spatial propagation model for mobile 3G smart antenna systems," Transactions on Communications, IEICE, Vol. 85, No. 1, 213-220, January 2003.

10. Hernando, J. and F. Perez, "Introduction to Mobile Communications Engineering," Chapter I, Artech House Pub., 1999.

11. Gorricho, M., C. Farre, J. Gorricho, A. Olive, and C. Quer, Comunicaciones Moviles, Ed. UPC, 2002.