1. Min, S., D. K. Seo, B. H. Lee, M. Kwon, and Y. H. Lee, "Direction of-arrival tracking scheme for DS/CDMA systems: Direction lock loop," IEEE Trans. Wireless Communication, Vol. 3, No. 99, 191-202, 2004.
doi:10.1109/TWC.2003.821215        Google Scholar

2. Yang, M., L. Sun, X. Yuan, and B. X. Chen, "A new nested MIMO array with increased degrees of freedom and hole-free difference coarray," IEEE Signal Processing Letters, Vol. 25, No. 1, 40-44, 2018.
doi:10.1109/LSP.2017.2766294        Google Scholar

3. Yao, B., Z. Dong, W. Zhang, W. Wang, and Q. Wu, "Degree-of-freedom strengthened cascade array for DOD-DOA estimation in MIMO array systems," Sensors, Vol. 18, No. 5, 1557, 2018.
doi:10.3390/s18051557        Google Scholar

4. Moffet, A., "Minimum-redundancy linear arrays," IEEE Transactions on Antennas and Propagation, Vol. 16, No. 2, 172-175, 1968.
doi:10.1109/TAP.1968.1139138        Google Scholar

5. Vaidyanathan, P. P. and P. Pal, "Sparse sensing with co-prime samplers and arrays," IEEE Transactions on Signal Processing, Vol. 59, No. 2, 573-586, 2011.
doi:10.1109/TSP.2010.2089682        Google Scholar

6. Qin, S., Y. D. Zhang, and M. G. Amin, "Generalized coprime array configurations for direction-of-arrival estimation," IEEE Transactions on Signal Processing, Vol. 63, No. 6, 1377-1390, 2015.
doi:10.1109/TSP.2015.2393838        Google Scholar

7. Pal, P. and P. P. Vaidyanathan, "Nested arrays: A novel approach to array processing with enhanced degrees of freedom," IEEE Transactions on Signal Processing, Vol. 58, No. 8, 4167-4181, 2010.
doi:10.1109/TSP.2010.2049264        Google Scholar

8. Yang, M., L. Sun, X. Yuan, and B. X. Chen, "Improved nested array with hole-free DCA and more degrees of freedom," Electronics Letters, Vol. 52, No. 9, 2068-2070, 2016.
doi:10.1049/el.2016.3197        Google Scholar

9. Iizuka, Y. and K. Ichige, "Extension of nested array for large aperture and high degree of freedom," IEICE Communications Express, Vol. 6, No. 6, 381-386, 2017.
doi:10.1587/comex.2017XBL0031        Google Scholar

10. Liu, S., L. S. Yang, D. Li, and H. L. Cao, "Subspace extension algorithm for 2D DOA estimation with L-shaped sparse array," Multidimensional Systems & Signal Processing, Vol. 28, 315-327, 2017.
doi:10.1007/s11045-016-0406-3        Google Scholar

11. Liu, S., J. Zhao, and Z. G. Xiao, "DOA estimation with sparse array under unknown mutual coupling," Progress In Electromagnetics Research Letters, Vol. 70, 147-153, 2017.
doi:10.2528/PIERL17081701        Google Scholar

12. Huang, H., B. Liao, X. Wang, X. S. Guo, and J. Huang, "A new nested array configuration with increased degrees of freedom," IEEE Access, Vol. 6, 1490-1497, 2018.
doi:10.1109/ACCESS.2017.2779171        Google Scholar

13. Shen, Q., W. Liu, and W. Cui, "Extension of nested arrays with the fourth-order difference co-array enhancement," IEEE International Conference on Acoustics, Speech and Signal Processing, 2991-2995, Shanghai, China, 2016.        Google Scholar

14. Ahmed, A., Y. D. Zhang, and B. Himed, "Effective nested array design for fourth-order cumulant-based DOA estimation," IEEE Radar Conference, 0998-1002, Seattle, WA, USA, 2017.        Google Scholar

15. Zhang, L., S. Ren, and X. Li, "Generalized L-shaped nested array concept based on the fourth-order difference co-array," Sensors, Vol. 18, 8, 2018.        Google Scholar

16. Ma, W. K., T. H. Hsieh, and C. Y. Chi, "DOA estimation of quasi-stationary signals with less sensors than sources and unknown spatial noise covariance a Khatri-Rao subspace approach," IEEE Transactions on Signal Processing, Vol. 58, No. 9, 2168-2180, 2010.
doi:10.1109/TSP.2009.2034935        Google Scholar

17. Schmidt, R. O., "Multiple emitter location and signal parameter estimation," IEEE Transactions on Antennas & Propagation, Vol. 34, No. 3, 276-280, 1986.
doi:10.1109/TAP.1986.1143830        Google Scholar