Sensitivity of the Adaptive Nulling to Random Errors in Amplitude and Phase Excitations in Array Elements


  • Jafar Ramadhan Mohammed College of Electronics Engineering, Ninevah University
  • Khalil Hassan Sayidmarie College of Electronics Engineering, Ninevah University


Adaptive Antennas, Antenna Arrays, Errors In Amplitude And Phase Excitations, Null Steering,


Adaptive antenna arrays have shown their effectiveness and powerful capabilities in modern communication and radar systems. However, maintaining this effectiveness under conditions of random errors in their element excitations is the most challenging problem. In this paper, the degradation in performance, exhibited as the elevation in the sidelobe level and changing the angular locations of the desired nulls, due to random errors in the phase and amplitude of the element excitations is investigated. First, an efficient constrained optimization approach was used to synthesize an adaptive linear array. The approach maximizes the gain in the desired direction and rejects undesired interfering signals by placing nulls towards their angles of arrivals. Then, the effects of random amplitude and phase errors in the element excitations were investigated. Simulation results showed that the nulls and the sidelobe level in the adaptive arrays are more sensitive to random errors in element phase excitations as compared to amplitude excitations.


Peter J. Bevelacqua and Constantine A. Balanis, "Minimum Sidelobe Levels for Linear Arrays," IEEE Trans. Antennas Propag., vol. 55, No. 12, pp. 3442-3449, December 2007.

Mohammed, J. R., “Phased Array Antenna with Ultra-Low Sidelobes”, Electronics Letters, Vol. 49, Issue 17, pp. 1055-1056, August 2013.

Lopez, P., Rodriguez, J. A., Ares, F. and Moreno, E., “Low Sidelobe Level In Almost Uniformly Excited Arrays”, Electron. Lett., Vol. 36, No. 24, pp. 1991-1993, 2000.

Haupt, R. L., "Phase-Only Adaptive Nulling with a Genetic Algorithm," IEEE Trans. on Antennas and Propagat., Vol. 45, No. 6, 1009-1015, 1997.

A. Tennant, M.M. Dawoud, and A.P. Anderson, "Array Pattern Nulling By Element Position Perturbations Using A Genetic Algorithm", Electron Lett., Vol. 30, pp. 174–176, 1994.

Ghayoula, R., Fadlallah, N., Gharsallah, A. and Rammal, M.," PhaseOnly Adaptive Nulling With Neural Networks For Antenna Array Synthesis", IET Microw. Antennas Propag., 2009, Vol. 3, Issue 1, pp. 154–163

Keizer, W. P. M. N. , "Low Sidelobe Phased Array Pattern Synthesis with Compensation for Errors Due to Quantized Tapering", IEEE Trans. Antennas Propagat., Vol.59, No. 12, pp. 4520-4524, Dec. 2011.

Pozar, D. M., and Kaufman, B., "Design Considerations for Low Sidelobe Microstrip Arrays", IEEE Trans. Antennas Propagat., Vol. 38, No. 8, pp. 1176-1185, Aug. 1990.

Fei Zhao, Huiying Qi, Ke Xiao, Lei Qiu, and Shunlian Chai, "The Experimental Study of Mutual Coupling in Conformal Array", Microwave and Optical Technology Letters, Vol. 54, No. 1, January 2012.

Mohammed, J. R. and Sayidmarie, K. H., “A New Technique for Obtaining Wide-Angular Nulling in the Sum and Difference Patterns of Monopulse Antenna”, IEEE Antennas and Wireless Propagation Letters, Vol.11, pp. 1242-1245, 2012.

Mohammed, J. R., “Design of Printed Yagi Antenna with Additional Driven Element for WLAN Applications”, Progress in Electromagnetics Research C, Vol. 37, 67-81, January 2013.

Mohammed, J. R. and Sayidmarie, K. H., "A Null Steering Method By Controlling Two Elements", IET Microwaves, Antennas & Propagation, Vol. 8, Issue 15, PP. 1348-1355, 2014.

Mohammed, J.R.," Optimal Null Steering Method in Uniformly Excited Equally Spaced Linear Array by Optimizing Two Edge Elements", Electronics Letters, Vol. 53, Issue 11, May 2017.

Mohammed, J.R and Sayidmarie, K. H., "Performance Evaluation of the Adaptive Sidelobe Canceller with various Auxiliary Configurations," AEÜ International Journal of Electronics and Communications, Vol. 80, pp. 179–185, 2017.

Mohammed, J.R and Sayidmarie, K. H., "Synthesizing Asymmetric SideLobe Pattern with Steered Nulling in Non-uniformly Excited Linear Arrays by Controlling Edge Elements," International Journal of Antennas and Propagation, Vol. 2017, Article ID 9293031, 8 pages, 2017.

Sayidmarie, K. H. and Mohammed, J. R., "Performance of a Wide Angle and Wideband Nulling Method for Phased Arrays", Progress in Electromagnetics Research M, Vol. 33, pp. 239-249, October 2013.

Li, J. and Stoica, P., “Robust Adaptive Beamforming”, John Wiley and Sons, Inc., Hoboken, New Jersey, 2006.

Yang, K., Zhao, Z., and Liu, Q. H. ,"Robust Adaptive Beamforming Against Array Calibration Errors", Progress In Electromagnetics Research., PIER. 140, pp. 341-351, 2013.

Hansen, E. and Walster, G. W., "Global Optimization Using Interval Analysis", New York, NY: CRC Press, 2004.




How to Cite

Mohammed, J. R., & Sayidmarie, K. H. (2018). Sensitivity of the Adaptive Nulling to Random Errors in Amplitude and Phase Excitations in Array Elements. Journal of Telecommunication, Electronic and Computer Engineering (JTEC), 10(1), 51–56. Retrieved from