access icon free Robust and rapid converging adaptive beamforming via a subspace method for the signal-plus-interferences covariance matrix estimation

The presence of the desired signal (DS) in the training snapshots makes the adaptive beamformer sensitive to any steering vector mismatch and dramatically reduces the convergence rate. Even the performance of the most of the existing robust adaptive beamformers is degraded when the signal-to-noise ratio (SNR) is increased. In this study, a high converging rate robust adaptive beamformer is proposed. This method is a promoted eigenspace-based beamformer. In this paper, a new signal-plus-interferences (SPI) covariance matrix estimator is proposed. The subspace of the ideal SPI covariance matrices is exploited and the estimated covariance matrix is projected into this subspace. This projection effectively reduces the covariance matrix estimation error and the proposed estimator yields a more accurate estimation of the SPI covariance matrix. In addition, a computationally efficient steering vector estimator has been proposed. To prevent the absence of the DS steering vector in the estimated SPI subspace, the estimated SPI covariance matrix is compensated. Hence, the proposed method can attain the optimal beamformer in the both high and low SNR cases. The numerical examples indicate that this method has excellent signal-to-interference plus noise ratio performance and offers a higher converging rate compared with the existing robust adaptive beamforming algorithms.

Inspec keywords: covariance matrices; interference (signal); array signal processing; eigenvalues and eigenfunctions; adaptive signal processing

Other keywords: SPI covariance matrix estimator; high converging rate robust adaptive beamformer; training snapshots; signal-to-interference plus noise ratio performance; signal-plus-interference covariance matrix estimation; steering vector estimator mismatch; DS steering vector; subspace method; convergence rate; desired signal; estimator yields; SNR; eigenspace-based beamformer

Subjects: Algebra; Signal processing theory; Signal processing and detection; Algebra

References

    1. 1)
    2. 2)
    3. 3)
    4. 4)
    5. 5)
    6. 6)
    7. 7)
    8. 8)
    9. 9)
    10. 10)
    11. 11)
    12. 12)
    13. 13)
    14. 14)
    15. 15)
    16. 16)
    17. 17)
    18. 18)
    19. 19)
    20. 20)
    21. 21)
    22. 22)
    23. 23)
    24. 24)
      • 25. Vorobyov, S.A., Gershman, A.B., Luo, Z.-Q., Ma, N.: ‘Adaptive beamforming with joint robustness against mismatched signal steering vector and interference nonstationarity’, IEEE Signal Process. Lett., 2004, 11, pp. 108111 (doi: 10.1109/LSP.2003.819857).
    25. 25)
      • 21. Lo, K.W.: ‘Improving performance of real-symmetric adaptive array by signal blocking’, IEEE Trans. Aerosp. Electron. Syst., 1995, 31, (2), pp. 821830 (doi: 10.1109/7.381928).
    26. 26)
      • 14. Yu, Z.L., Ser, W., Er, M.H.: ‘Robust adaptive beamformer with LMI constraints on magnitude response’. Proc. IEEE Int. Conf. Communications, Beijing, China, May 2008, pp. 815819.
    27. 27)
      • 10. Khabbazibasmenj, A., Vorobyov, S.A., Hassanien, A.: ‘Robust adaptive beamforming based on steering vector estimation with as little as possible prior information’, IEEE Trans. Signal Process., 2012, 60, (6), pp. 29742987 (doi: 10.1109/TSP.2012.2189389).
    28. 28)
      • 15. Ye, Z., Liu, C.: ‘Non-sensitive adaptive beamforming against mutual coupling’, IET Signal Process., 2009, 3, (1), pp. 16 (doi: 10.1049/iet-spr:20070198).
    29. 29)
      • 23. Kim, J.W., Un, C.K.: ‘An adaptive array robust to beam pointing error’, IEEE Trans. Signal Process., 1992, 40, pp. 15821584 (doi: 10.1109/78.139266).
    30. 30)
      • 4. Pedersen, K.I., Mogensen, P.E., Fleury, B.H.: ‘A stochastic model of the temporal and azimuthal dispersion seen at the base station in outdoor propagation environments’, IEEE Trans. Veh. Technol., 2000, 49, pp. 437447 (doi: 10.1109/25.832975).
    31. 31)
      • 12. Shahbazpanahi, S., Gershman, A.B., Luo, Z.Q., Wong, K.M.: ‘Robust adaptive beamforming for general-rank signal models’, IEEE Trans. Signal Process., 2003, 51, (9), pp. 22572269 (doi: 10.1109/TSP.2003.815395).
    32. 32)
      • 24. Chang, L., Yeh, C.C.: ‘Performance of DMI and eigenspace-based beamformers’, IEEE Trans. Signal Process., 1992, 40, pp. 13361347.
    33. 33)
      • 31. Boyd, S.: ‘Convex optimization’ (Cambridge University Press, 2009).
    34. 34)
      • 19. Zhuang, J.: ‘Robust adaptive array beamforming with subspace steering vector uncertainties’, IEEE Signal Process. Lett., 2012, 19, pp. 785788 (doi: 10.1109/LSP.2012.2221709).
    35. 35)
      • 16. Yu, L., Liu, W., Langley, R.J.: ‘Novel robust beamformers for coherent interference suppression with DOA estimation errors’, IET Microw. Antennas Propag., 2010, 4, (9), pp. 13101319 (doi: 10.1049/iet-map.2009.0433).
    36. 36)
      • 18. Chen, C.Y., Vaidyanathan, P.P.: ‘Quadratically constrained beamforming robust against direction-of-arrival mismatch’, IEEE Trans. Antennas Propag., 2007, 55, (8), pp. 41394150.
    37. 37)
      • 9. Hassanien, A., Vorobyov, S.A., Wong, K.M.: ‘Robust adaptive beamforming using sequential quadratic programming: an iterative solution to the mismatch problem’, IEEE Signal Process. Lett., 2008, 15, pp. 733736 (doi: 10.1109/LSP.2008.2001115).
    38. 38)
      • 8. Vorobyov, S.A., Gershman, A.B., Luo, Z.Q.: ‘Robust adaptive beamforming using worst-case performance optimization: A solution to the signal mismatch problem’, IEEE Trans. Signal Process., 2003, 51, (2), pp. 313324 (doi: 10.1109/TSP.2002.806865).
    39. 39)
      • 1. Brennan, L.E., Mallet, J.D., Reed, I.S.: ‘Adaptive arrays in airborne MTI radar’, IEEE Trans. Antennas Propag., 1976, 24, pp. 607615 (doi: 10.1109/TAP.1976.1141412).
    40. 40)
      • 5. Godara, L.C.: ‘The effect of phase-shifter errors on the performance of an antenna-array beamformer’, IEEE J. Ocean Eng., 1985, OE-10, pp. 278284 (doi: 10.1109/JOE.1985.1145105).
    41. 41)
      • 20. Ruebsamen, M., Gershman, A.B.: ‘Robust adaptive beamforming using multi-dimensional covariance fitting’, IEEE Trans. Signal Process., 2012, 60, pp. 740753 (doi: 10.1109/TSP.2011.2174233).
    42. 42)
      • 7. Carlson, B.D.: ‘Covariance matrix estimation errors and diagonal loading in adaptive arrays’, IEEE Trans. Aerosp. Electron. Syst., 1988, 24, (4), pp. 397401 (doi: 10.1109/7.7181).
    43. 43)
      • 3. Feldman, D.D., Griffiths, L.J.: ‘A projection approach for robust adaptive beamforming’, IEEE Trans. Signal Process., 1994, 42, pp. 867876 (doi: 10.1109/78.285650).
    44. 44)
      • 6. Widrow, B., Duvall, K.M., Gooch, R.P., Newman, W.C.: ‘Signal cancellation phenomena in adaptive antennas: causes and cures’, IEEE Trans. Antennas Propag., 1982, 30, (3), pp. 469478 (doi: 10.1109/TAP.1982.1142804).
    45. 45)
      • 28. Blunt, S.D., Chan, T., Gerlach, K.: ‘Robust DOA estimation: the re-iterative super-resolution (RISR) algorithm’, IEEE Trans. Aerosp. Electron. Syst., 2011, 47, (1), pp. 332346 (doi: 10.1109/TAES.2011.5705679).
    46. 46)
      • 17. Li, J., Stoica, P., Wang, Z.: ‘On robust capon beamforming and diagonal loading’, IEEE Trans. Signal Process., 2003, 51, (7), pp. 17021715 (doi: 10.1109/TSP.2003.812831).
    47. 47)
      • 27. Lei, L., Lie, J.P., Gershman, A.B.: ‘Robust adaptive beamforming in partly calibrated sparse sensor arrays’, IEEE Trans. Signal Process., 2010, 58, pp. 16611667 (doi: 10.1109/TSP.2009.2037852).
    48. 48)
      • 30. Meyer, C.D.: ‘Matrix analysis and applied linear algebra’ (SIAM, 2001).
    49. 49)
      • 11. Rahmani, M., Bastani, M.H., Shahraeeni, S.: ‘Two layers beamforming robust against direction-of-arrival mismatch’, IET Signal Process., accepted (DOI: 10.1049/iet-spr.2013.0031).
    50. 50)
      • 26. Li, J., Stoica, P., Wang, Z.: ‘Doubly constrained robust capon beamformer’, IEEE Trans. Signal Process., 2004, 52, pp. 24072423 (doi: 10.1109/TSP.2004.831998).
    51. 51)
      • 2. Van Trees, H.L.: ‘Optimum array processing. Part IV of detection, estimation, and modulation theory’ (Wiley, 2002).
    52. 52)
      • 13. Takao, K., Fujita, M., Nishi, T.: ‘An adaptive antenna array under directional constraint’, IEEE Trans. Antennas Propag., 1976, AP-24, (5), pp. 662669 (doi: 10.1109/TAP.1976.1141411).
    53. 53)
      • 22. Gershman, A.B., Sidiropoulos, N.D., Shahbazpanahi, S., Bengtsson, M., Ottersten, B.: ‘Convex optimization-based beamforming’, IEEE Signal Process. Mag., 2010, 27, pp. 6275 (doi: 10.1109/MSP.2010.936015).
    54. 54)
      • 29. Li, J., Stoica, P.: ‘Robust adaptive beamforming’ (John Wiley, 2005).
http://iet.metastore.ingenta.com/content/journals/10.1049/iet-spr.2013.0298
Loading

Related content

content/journals/10.1049/iet-spr.2013.0298
pub_keyword,iet_inspecKeyword,pub_concept
6
6
Loading