volume | PIER Journals

Abstract

MVDR beamformer is one of the well-known adaptive beamforming techniques that offers the ability to resolve signals that are separated by a fraction of an antenna beamwidth. In an ideal scenario, the MVDR beamformer can not only minimize the array output power but also maintain a distortionless mainlobe response toward the desired signal. Unfortunately, the MVDR beamformer may have unacceptably low nulling level, which may lead to signicant performance degradation in the case of unexpected interfering signals. A new robust MVDR beamforming is presented to control the nulling level of adaptive antenna array. In this proposed approach, the beamforming optimization problem is formulated as a multi-parametric quadratic programming (mp-QP) problem such that the optimal weight vector can be easily obtained by real-valued computation. The presented method can guarantee that the nulling level are strictly below the prescribed threshold. Simulation results are presented to verify the efficiency of the proposed method.

1. Capon, J., "High-resolution frequency-wavenumber spectrum analysis," Proc. IEEE, Vol. 57, 1408-1418, 1969.
doi:10.1109/PROC.1969.7278 Google Scholar

2. Joseph, R. G., "Theory and application of covariance matrix tapers for robust adaptive beamforming," IEEE Transactions on Signal Processing, Vol. 47, No. 4, 977-985, 1999.
doi:10.1109/78.752596 Google Scholar

3. Zatman, M., "Comments on theory and application of covariance matrix tapers for robust adaptive beamforming," IEEE Transactions on Signal Processing, Vol. 48, No. 6, 1796-1800, 2000.
doi:10.1109/78.845937 Google Scholar

4. Liu, F. L., R. Y. Du, J. K.Wang, and B.Wang, "A robust adaptive control method for widening interference nulls," IET International Radar Conference, Guilin, China, 2009. Google Scholar

5. Liu, F. L., C. Y. Sun, and J. K. Wang, "An effective nulls control method based on semidefinite programming," NDCC, Qinhuangdao, China, 2010. Google Scholar

6. Liu, F. L., C. Y. Sun, J. K. Wang, and R. Y. Du, "A robust adaptive beamforming optimization control method via second-order cone programming for bistatic MIMO radar systems," ICIC Express Letters, Vol. 4, No. 5(B), 1823-1830, 2010. Google Scholar

7. Xing, Z. Q., "Transmitting beamforming technique with widen null based on zero space," Communications Technology, Vol. 40, No. 11, 22-24, 2007. Google Scholar

8. Yu, Z. K. and S. Y. Yang, "Research on the wide nulling algorithm," Applied Science and Technology, Vol. 33, No. 3, 1-3, 2006. Google Scholar

9. Xie, H., Y. Li, and Y. N. Zhao, "Research on widened nulling under drastic interference angle shaking," Applied Science and Technology, Vol. 34, No. 7, 34-37, 2007. Google Scholar

10. Zeng, Y. B., "Array pattern nulling by amplitude-only perturbations," Journal of Electronics & Information Technology, Vol. 28, No. 11, 2073-2076, 2006. Google Scholar

11. He, Q.-Q., H.-D. He, and H. Lan, "An efficient patterns syntheis method for cylindrical pahsed array antennas," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 4, 473-482, 2009.
doi:10.1163/156939309787612329 Google Scholar

12. Petter, T., T. A. Johansen, and A. Bemporad, "An algorithm for multi-parametric quadratic programming and explicit MPC solutions ," Proceedings of the 40th IEEE Conference on Decision and Control, Orlando, FL, USA, 2002. Google Scholar

13. Bemporad, A., M. Morari, V. Dua, and E. E. Pistikopulos, "The explicit linear quadratic regular for constrained systems," Automatica, Vol. 38, No. 1, 3-20, 2002.
doi:10.1016/S0005-1098(01)00174-1 Google Scholar

14. Ayestarán, R. G., M. F. Campillo, and F. Las-Hears, "Multiple support vector regression for antenna array characterization and synthesis ," IEEE Transactions on Antennas and Propagation, Vol. 55, No. 9, 2495-2501, 2007.
doi:10.1109/TAP.2007.904077 Google Scholar

Prof. Fulai Liu

Professor Jinkuan Wang

Dr. C. Y. Sun

Dr. Ruiyan Du