Vol. 94
Latest Volume
All Volumes
PIERB 109 [2024] PIERB 108 [2024] PIERB 107 [2024] PIERB 106 [2024] PIERB 105 [2024] PIERB 104 [2024] PIERB 103 [2023] PIERB 102 [2023] PIERB 101 [2023] PIERB 100 [2023] PIERB 99 [2023] PIERB 98 [2023] PIERB 97 [2022] PIERB 96 [2022] PIERB 95 [2022] PIERB 94 [2021] PIERB 93 [2021] PIERB 92 [2021] PIERB 91 [2021] PIERB 90 [2021] PIERB 89 [2020] PIERB 88 [2020] PIERB 87 [2020] PIERB 86 [2020] PIERB 85 [2019] PIERB 84 [2019] PIERB 83 [2019] PIERB 82 [2018] PIERB 81 [2018] PIERB 80 [2018] PIERB 79 [2017] PIERB 78 [2017] PIERB 77 [2017] PIERB 76 [2017] PIERB 75 [2017] PIERB 74 [2017] PIERB 73 [2017] PIERB 72 [2017] PIERB 71 [2016] PIERB 70 [2016] PIERB 69 [2016] PIERB 68 [2016] PIERB 67 [2016] PIERB 66 [2016] PIERB 65 [2016] PIERB 64 [2015] PIERB 63 [2015] PIERB 62 [2015] PIERB 61 [2014] PIERB 60 [2014] PIERB 59 [2014] PIERB 58 [2014] PIERB 57 [2014] PIERB 56 [2013] PIERB 55 [2013] PIERB 54 [2013] PIERB 53 [2013] PIERB 52 [2013] PIERB 51 [2013] PIERB 50 [2013] PIERB 49 [2013] PIERB 48 [2013] PIERB 47 [2013] PIERB 46 [2013] PIERB 45 [2012] PIERB 44 [2012] PIERB 43 [2012] PIERB 42 [2012] PIERB 41 [2012] PIERB 40 [2012] PIERB 39 [2012] PIERB 38 [2012] PIERB 37 [2012] PIERB 36 [2012] PIERB 35 [2011] PIERB 34 [2011] PIERB 33 [2011] PIERB 32 [2011] PIERB 31 [2011] PIERB 30 [2011] PIERB 29 [2011] PIERB 28 [2011] PIERB 27 [2011] PIERB 26 [2010] PIERB 25 [2010] PIERB 24 [2010] PIERB 23 [2010] PIERB 22 [2010] PIERB 21 [2010] PIERB 20 [2010] PIERB 19 [2010] PIERB 18 [2009] PIERB 17 [2009] PIERB 16 [2009] PIERB 15 [2009] PIERB 14 [2009] PIERB 13 [2009] PIERB 12 [2009] PIERB 11 [2009] PIERB 10 [2008] PIERB 9 [2008] PIERB 8 [2008] PIERB 7 [2008] PIERB 6 [2008] PIERB 5 [2008] PIERB 4 [2008] PIERB 3 [2008] PIERB 2 [2008] PIERB 1 [2008]
2021-11-08
A Review of Metasurface-Assisted RCS Reduction Techniques
By
Progress In Electromagnetics Research B, Vol. 94, 75-103, 2021
Abstract
This review discusses the evolution of the various radar cross-section (RCS) reduction techniques, with an emphasis on metasurfaces. The paper first introduces the terms RCS and RCS reduction and then discusses conventional and modern techniques to reduce RCS. The two main strategies used are scattering and absorption. The traditional methods of shaping and Radar Absorbing Material (RAM) are first briefly reviewed, followed by an extensive review of metasurface-based RCS reduction. RCS-reducing metasurfaces have the unique characteristics of acting as scatterers and absorbers. They are also described with regard to their passive and active configurations. The RCS reduction techniques are discussed with respect to profile, bandwidth, angular stability, polarization sensitivity, design complexity, and cost-effectiveness. A comprehensive comparison chart based on the performance parameters such as bandwidth, size and angular stability is tabulated for the different types of metasurfaces. The review also details areas that require further investigation.
Citation
Akila Murugesan, Krishnasamy Selvan, Ashwin K. Iyer, Kumar Vaibhav Srivastava, and Arokiaswami Alphones, "A Review of Metasurface-Assisted RCS Reduction Techniques," Progress In Electromagnetics Research B, Vol. 94, 75-103, 2021.
doi:10.2528/PIERB21081401
References

1. "IEEE Standard for Radar Definitions," IEEE Std 686-2017 (Revision of IEEE Std 686-2008), 1-54, Sept. 13, 2017.

2. Knott, E. F., J. F. Shaeffer, and M. T. Tuley, Radar Cross Section, SciTech Pub, 2004.
doi:10.1049/SBRA026E

3. Dobrenz, L. T., A. Spadoni, and M. Jorgensen, "Aviation archeology of the horten 229 v3 aircraft," 10th AIAA Aviation Technology, Integration and Operations (ATIO) Conference, Texas, 2010.

4. Ufimtsev, P. Y., "Method of edge waves in the physical theory of diffraction," Soviet Radio, Moscow, 1962.

5. Goodall, J. C., Lockheed SR-71 Blackbird: The Illustrated History of America's Legendary Mach 3 Spy Plane, Schiffer Publishing Ltd, 2018.

6. Yu, N. and F. Capasso, "Flat optics with designer metasurfaces," Nature Materials, 139-150, 2014.
doi:10.1038/nmat3839

7. Iyer, A. K., A. Alu, and A. Epstein, "Metamaterials and metasurfaces --- Historical context, recent advances, and future directions," IEEE Transactions on Antennas and Propagation, Vol. 68, No. 3, 1223-1231, 2020.
doi:10.1109/TAP.2020.2969732

8. Bukhari, S. S., Y. J. Vardaxoglou, and W. Whittow, "A metasurfaces review: Definitions and applications," Applied Sciences, Vol. 9, No. 13, 2019.
doi:10.3390/app9132727

9. Chen, H.-T., A. J. Taylor, and N. Yu, "A review of metasurfaces: Physics and applications," Reports on Progress in Physics, Vol. 79, No. 7, 2016.
doi:10.1088/0034-4885/79/7/076401

10. Chen, M., M. Kim, A. M. H. Wong, and G. V. Eleftheriades, "Huygens' metasurfaces from microwaves to optics: A review," Nanophotonics, Vol. 7, No. 6, 1207-1231, 2018.
doi:10.1515/nanoph-2017-0117

11. Fan, Y., J. Wang, X. Fu, Y. Li, Y. Pang, L. Zheng, M. Yan, J. Zhang, and S. Qu, "Recent developments of metamaterials/metasurfaces for RCS reduction," EPJ Applied Metamaterials, Vol. 6, No. 15, 2019.

12. Zaker, R. and A. Sadeghzadeh, "Passive Techniquesfor target radar cross section reduction: A comprehensive review," International Journal of RF and Microwave Computer-Aided Engineering, Vol. 30, No. 11, 2020.
doi:10.1002/mmce.22411

13. Teruel, O. Q., H. Chen, A. Diaz Rubio, G. Gok, A. Grbic, G. Minatti, E. Martini, S. Maci, G. V. Eleftheriades, M. Chen, N. I. Zheludev, N. Papasimakis, S. Choudhury, Z. A. Kudyshev, S. Saha, H. Reddy, A. Boltasseva, V. M. Shalaev, V. A. Kildishev, D. Sievenpiper, C. Caloz, A. Alu, Q. He, L. Zhou, G. Valerio, E. Rajo-Iglesias, Z. Sipus, F. Mesa, R. R. Berral, F. Medina, V. Asadchy, S. Tretyakov and C. Craeye, "Roadmap on metasurfaces," Journal of Optics, Vol. 21, No. 7, 2019.

14. Maggiora, R., M. Saccani, and D. Milanesio, "An innovative harmonic radar to track flying insects: The case of vespa velutina," Sci. Rep., Vol. 9, 2019.

15. Jeng, S.-L., W.-H. Chieng, and H.-P. Lu, "Estimating speed using a side-looking single-radar vehicle detector," IEEE Transactions on Intelligent Transportation Systems, Vol. 15, No. 2, 607-614, 2014.
doi:10.1109/TITS.2013.2283528

16. Vinoy, K. J. and R. M. Jha, "Trends in radar absorbing materials technology," Sadhana, Vol. 20, 815-850, 1995.
doi:10.1007/BF02744411

17. Guo, W. L., K. Chen, G. M. Wang, X. Y. Luo, Y. J. Feng, and C. W. Qiu, "Transmission-Reflection-Selective metasurface and its application to RCS reduction of high-gain reflector antenna," IEEE Transactions on Antennas and propagation, Vol. 68, No. 3, 1426-1435, Mar. 2020.
doi:10.1109/TAP.2019.2948742

18. Rao, G. A. and S. P. Mahulikar, "Integrated review of stealth technology and its role in airpower," The Aeronautical Journal, Vol. 106, 629-642, 1968.

19. Howe, D., "Introduction to the basic technology of stealth aircraft: Part 2 --- Illumianation by the enemy (active considerations)," ASME Journal of Engineering for Gas Turbine and Power, Vol. 113, No. 75, 80-86, Jan. 1991.
doi:10.1115/1.2906534

20. Franscis, R. H., "The development of blue steel," The Aeronautical Journal, Vol. 68, No. 641, 303-322, 1964.

21. Bao, G. and J. Lai, "Optimal shape design of a cavity for radar cross section reduction," SIAM Journal on Control and Optimization, Vol. 52, No. 4, 2122-2140, 2014.
doi:10.1137/130905708

22. Peixoto, G. G., A. L. de Paula, L. A. Andrade, C. M. A. Lopes, and M. C. Rezende, "Radar Absorbing Material (RAM) and shaping on radar cross section reduction of dihedral corners," SBMO/IEEE MTT-S International Conference on Microwave and Optoelectronics, Brasilia, 2005.

23. Swandic, J. R., Bandwidth limits and other considerations for monostatic RCS reduction by virtual shaping, Naval Surface Warfare Center, 2004.

24. Saville, P., Review of radar absorbing materials, Defence R&D Canada, Atlantic, Dartmouth, 2005.

25. Ali, Z., B. Muneer, B. S. Chowdry, S. Jehangir, and G. Hyder, "Design of microwave pyramidal absorber for semi anechoic chamber in 1 GHz ~ 20 GHz range," International Journal of Wireless and Microwave Technologies, Vol. 10, No. 2, 22-29, 2020.
doi:10.5815/ijwmt.2020.02.03

26. Sweetman, B., "Stealth aircraft-history, technology and outlook," Gas Turbine and Aeroengine Congress and Exposition, Brussels, 1990.

27. Berenger, J. P., "A perfectly matched layer for the absorption of electromagnetic waves," Journal of Computational Physics, Vol. 114, No. 2, 185-200, 1994.
doi:10.1006/jcph.1994.1159

28. Salisbury, W. W., Absorbent body for electromagnetic waves, US Patent 2599944, Jun. 10, 1952.

29. Chambers, B. and A. Tennant, "Optimized design of jaumann radar absorbing materials using a genetic algorithm," IEE Proceedings --- Radar, Sonar and Navigation, Vol. 143, No. 1, 23-30, 1996.
doi:10.1049/ip-rsn:19960316

30. Selvanayagam, M. and G. V. Eleftheriades, "Discontinuous electromagnetic fields usingorthogonal electric and magnetic currents for wavefront manipulation," Optics Express, Vol. 21, No. 12, 14409-14429, 2013.
doi:10.1364/OE.21.014409

31. Wong, J. P. S., M. Selvanayagam, and G. V. Eleftheriades, "Design of unit cells and demonstration of methods for synthesizing Huygens metasurfaces," Photonics and Nanostructures --- Fundamentals and Applications, Vol. 12, No. 4, 360-375, 2014.
doi:10.1016/j.photonics.2014.07.001

32. Pfeiffer, C. and A. Grbic, "Metamaterial Huygens' surfaces: Tailoring wave fronts with reflectionless sheets," Physics Review Letters, Vol. 110, No. 19, 197401, 2013.
doi:10.1103/PhysRevLett.110.197401

33. Epstein, A. and G. V. Eleftheriades, "Shielded perfect reflectors based on omega-bianisotropic metasurfaces," International Workshop on Antenna Technology: Small Antennas, Innovative Structures, and Applications (iWAT), Athens, Greece, 2017.

34. Selvanayagam, M. and G. V. Eleftheriades, "Polarization control using tensor Huygens surfaces," IEEE Transactions on Antennas and Propagation, Vol. 62, No. 12, 6155-6168, 2014.
doi:10.1109/TAP.2014.2359208

35. Pfeiffer, C. and A. Grbic, "Bianisotropic metasurfaces for optimal polarization control: Analysis and synthesis," Physical Review Applied, 2014.

36. Yu, N. Y., P. Genevet, M. A. Kats, F. Aieta, J.-P. Tetienne, F. Capasso, and Z. Gaburro, "Light propagation with phase discontinuities: Generalized laws of reflection and refraction," Science, Vol. 334, No. 6054, 333-337, Oct. 21, 2011.
doi:10.1126/science.1210713

37. Sun, S., K.-Y. Yang, C.-M. Wang, T.-K. Juan, W. T. Chen, C. Y. Liao, D. He, S. Xiao, W.-T. Kung, G.-Y. Guo, L. Zhou, and D. P. Tsai, "High-efficiency broadband anomalous reflection by gradient metasurfaces," Nano Letters, Vol. 12, No. 12, 6223-6229, Nov. 28, 2012.
doi:10.1021/nl3032668

38. Sun, S., Q. He, S. Xiao, Q. Xu, X. Li, and L. Zhou, "Gradient-index meta-surfaces as a bridge linking propagating waves and surface waves," Nature Materials, Vol. 11, 426-431, 2012.
doi:10.1038/nmat3292

39. Pu, M., P. Chen, C. Wang, Y. Wang, Z. Zhao, C. Hu, C. Huang, and X. Luo, "Broadband anomalous reflection based on Gradient low-Q meta-surface," AIP Advances, Vol. 3, 052136, 2013.

40. Li, Y., J. Zhang, S. Qu, J. Wang, H. Chen, Z. Xu, and A. Zhang, "Wideband radar cross section reduction using two-dimensional phase gradient metasurface," Applied Physics Letters, Vol. 221110, 2014.

41. Chen, J., Q. Cheng, J. Zhao, D. S. Dong, and T. J. Cui, "Reduction of radar cross section based on a metasurface," Progress In Electromagnetics Research, Vol. 146, 71-76, 2014.
doi:10.2528/PIER14022606

42. Cheng, Y., C. Wu, J. Yang, X. Peii, F. Jia, and R. Gong, "An ultra-thin dual-band phase-gradient metasurface using hybrid resonant structures for backward RCS reduction," Applied Physics B, Vol. 143, Apr. 18, 2017.

43. Zheng, Q., Y. Li, J. Zhang, J. Wang, H. Ma, Y. Pang, Y. Han, S. Sui, Y. Shen, H. Chen, and S. Qu, "Wideband, wide-angle coding phase gradient metasurfaces based on Pancharatnam-Berry phase," Scientific Reports, Vol. 7, 43543, 2017.
doi:10.1038/srep43543

44. Azizi, Y., M. Soleimani, and S. H. Sedighy, "Ultra-wideband radar cross section reduction using amplitude and phase gradient modulated surface," Journal of Applied Physics, Vol. 128, No. 20, 2020.
doi:10.1063/5.0009651

45. Zhang, W., Y. Liu, S. Gong, J. Wang, and Y. Jiang, "Wideband RCS reduction of a slot array antenna using phase gradient metasurface," IEEE Antennas and Wireless Propagation Letters, Vol. 17, No. 12, 2193-2197, Dec. 2018.
doi:10.1109/LAWP.2018.2870863

46. Murugesan, A. and K. T. Selvan, "On further enhancing the bandwidth of wideband RCS reduction checkerboard metasurfaces using an optimization algorithm," International Journal of RF and Microwave Computer-Aided Engineering, Vol. 31, No. 7, e22686, 2021.
doi:10.1002/mmce.22686

47. Paquay, M., J.-C. Iriarte, I. Ederra, R. Gonzalo, and P. D. Maagt, "Thin AMC structure for radar cross-section reduction," IEEE Transactions on Antennas and Propagation, Vol. 55, No. 12, 3630-3638, Dec. 2007.
doi:10.1109/TAP.2007.910306

48. De Cos, M. E., Y. Alvarez-Lopez, and F. L. H. Andres, "A novel approach for RCS reduction using a combination of artificial magnetic conductors," Progress In Electromagnetics Research, Vol. 107, 147-159, 2010.
doi:10.2528/PIER10060402

49. Fu, Y., Y. Li, and N. Yuan, "Wideband composite AMC surfaces for RCS reduction," Microwave and Optical Technology Letters, Vol. 53, No. 4, 712-715, 2011.
doi:10.1002/mop.25835

50. Galarregyi, J. C. I., A. T. Pereda, J. L. M. D. Falcon, I. Ederra, R. Gonzalo, and P. D. Maagt, "Broadband radar cross-section reduction using AMC technoogy," IEEE Transactions on Antennas and Propagation, Vol. 61, No. 12, 6136-6143, 2013.
doi:10.1109/TAP.2013.2282915

51. Chen, W., C. A. Balanis, and C. R. Britcher, "Checkerboard EBG surfaces for wideband radar cross section reduction," IEEE Transactions on Antennas and Propagation, Vol. 63, No. 6, 263-264, Jun. 2015.

52. Chen, W., C. A. Balanis, and R. C. Birtcher, "Dual wide-band checkerboard surfaces for radar cross section reduction," IEEE Transactions on Antennas and Propagation, Vol. 64, No. 9, 4133-4138, Sept. 2016.
doi:10.1109/TAP.2016.2583505

53. Modi, A. Y., C. A. Balanis, C. R. Birtcher, and H. N. Shaman, "Novel design of ultrabroadband radar cross section reduction surfaces using artificial magnetic conductor," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 10, 5406-5417, Oct. 2017.
doi:10.1109/TAP.2017.2734069

54. Sang, D., Q. Chen, L. Ding, M. Guo, and Y. Fu, "Design of checkerboard AMC structure for wideband RCS reduction," IEEE Transactions on Antennas and Propagation, Vol. 67, No. 4, 2604-2012, Apr. 2019.
doi:10.1109/TAP.2019.2891657

55. Kim, S. H. and Y. J. Yoon, "Wideband radar cross-section reduction on checkerboard metasurfaces with surface wave suppression," IEEE Antenna and Wireless Propagation Letters, Vol. 18, No. 5, 896-900, 2019.
doi:10.1109/LAWP.2019.2905012

56. Su, J., J. Lu, Y. Yang, Z. Li, and J. Song, "A novel checkerboard metasurface based on optimized multielement phase cancellation for superwideband RCS redcution," IEEE Transaction on Antennas and Propagation, Vol. 66, No. 12, 7091-7099, 2018.
doi:10.1109/TAP.2018.2870372

57. Zaker, R. and A. Sadegnzadeh, "Wideband radar cross section reduction using a noveldesign of artificial magnetic conductor structure with a triple-layer configuration," International Journal of RF and Microwave Computer-Aided Engineering, Vol. 19, No. 2, e21545, Oct. 2018.
doi:10.1002/mmce.21545

58. Modi, A. Y., C. A. Balanis, R. C. Britcher, and H. N. Shaman, "New class of RCS reduction metasurfaces based on scattering cancellation array theory," IEEE Transactions on Antennas and Propagation, Vol. 67, No. 1, 298-308, Jan. 2019.
doi:10.1109/TAP.2018.2878641

59. Murugesan, A., D. Natarajan, and K. T. Selvan, "Low-cost, wideband checkerboard metasurface for monostatic RCS reduction," IEEE Antennas and Wireless Propagation Letters, Vol. 20, No. 4, 493-497, Apr. 2021.
doi:10.1109/LAWP.2021.3054863

60. Modi, A. Y., M. A. Alyahya, C. A. Balanis, and R. C. Birtcher, "Metasurface-based method for broadband RCS reduction of dihedral corner reflectors with multiple bounces," IEEE Transactions on Antennas and Propagation, Vol. 68, No. 3, 1436-1447, Mar. 2020.
doi:10.1109/TAP.2019.2940494

61. Chen, W., C. A. Balanis, C. R. Birtcher, and A. Y. Modi, "Cylindrically curved checkerboard surfaces for radar cross-section reduction," IEEE Antennas and Wireless Propagation Letters, Vol. 17, No. 2, 343-346, Feb. 2018.
doi:10.1109/LAWP.2018.2789906

62. Akbari, M., F. Samadi, A.-R. Sebak, and T. A. Denidni, "Superbroadband diffuse wave scattering based on coding metasurfaces: Polarization conversion metasurfaces," IEEE Antennas and Propagation Magazine, Vol. 61, No. 2, 40-52, Apr. 2019.
doi:10.1109/MAP.2019.2896218

63. Chen, H., J. Wang, H. Ma, S. Qu, Z. Xu, A. Zhang, M. Yan, and Y. Li, "Ultra-wideband polarization conversion metasurfaces based on multiple plasmon resonances," Journal of Applied Physics, Vol. 115, 2014.
doi:10.1063/1.4862166

64. Jiang, W., Y. Xue, and S.-X. Gong, "Polarization conversion metasurface for broadband radar cross section reduction," Progress In Electromagnetics Research Letters, Vol. 62, 9-15, 2016.
doi:10.2528/PIERL16060504

65. Jia, Y., Y. Liu, K. Li, and S.-X. Gong, "Broadband polarization rotation reflective surfaces and their applications to RCS reduction," IEEE Transactions on Antennas and Propagation, Vol. 64, No. 1, 179-188, Jan. 2016.
doi:10.1109/TAP.2015.2502981

66. Sun, H., C. Gu, X. Chen, L. Liu, B. Xu, and Z. Zhou, "Broadband and broad-angle polarization-independent metasurface for radar cross section reduction," Scientific Reports, Vol. 7, Jan. 20, 2017.

67. Jia, Y., Y. Liu, J. Y. Guo, K. Li, and S. Gong, "A dual-patch polarization rotation reflective surface and its application to ultra-wideband RCS reduction," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 6, 3291-3295, Jun. 2017.

68. Ameri, E., S. H. Esmaeli, and S. H. Sedighy, "Ultra wideband radar cross section reduction by using polarization conversion metasurfaces," Scientific Reports, Vol. 9, Jan. 24, 2019.

69. Yang, J. J., Y. Z. Cheng, C. C. Ge, and R. Z. Gong, "Broadband polarization conversion metasurface based on metal cut-wire structure for radar cross section reduction," Materials, Vol. 11, No. 4, 626, 2018.

70. Rajabalipanah, H. and A. Abdolali, "Ultrabroadband monostatic/bistatic RCS reduction via high-entrophy phase-encoded polarization conversion metasurfaces," IEEE Antennas and Wireless Propagation Letters, Vol. 18, No. 6, 1233-1237, Jun. 2019.

71. Dai, H., Y. Zhao, J. Chen, C. Yu, and L. Xing, "Ultra-wideband radar cross-section reduction using polarization conversion metasurface," International Journal of RF and Microwave Computer-Aided Engineering, e22085, Dec. 11, 2019.

72. Fu, C., L. Han, C. Liu, Z. Sun, and X. Lu, "Dual-band polarization conversion metasurface for RCS reduction," IEEE Transactions on Antennas and Propagation, Vol. 69, No. 5, 3044-3049, May 2021.

73. Long, M., W. Jiang, and S. Gong, "Wideband RCS reduction using polarization conversion metasurface and partially reflecting surface," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 2534-2537, 2017.

74. Sun, S., W. Jiang, X. Li, P. Liu, and S. Gong, "Ultrawideband high-efficiency 2.5-dimensional polarization conversion metasurface and its application in RCS reduction of antenna," IEEE Antenna and Wireless Propagation Letters, Vol. 18, No. 5, 881-885, 2019.

75. Hong, T., S. Wang, Z. Liu, and S. Gong, "RCS reduction and gain enhancement for the circularly polarized array by polarization conversion metasurface coating," IEEE Antennas and Wireless Propagation Letters, Vol. 18, No. 1, 167-171, Jan. 2019.

76. Liu, Y., K. Li, Y. Jia, Y. Hao, S. Gong, and Y. J. Guo, "Wideband RCS reduction of a slot array antenna using polarization conversion metasurface," IEEE Transactions on Antennas and Propagation, Vol. 64, No. 1, 326-331, Jan. 2016.

77. Qi, Y., B. Zhang, C. Li, and X. Deng, "Ultra-broadband polarization conversion meta-surface and its application in polarization converter and RCS reduction," IEEE Access, Vol. 8, 116675-116684, 2010.

78. Giovampaola, C. D. and N. Engheta, "Digital metamaterials," Nature Materials, Vol. 13, 1115-1121, 2014.

79. Cui, T. J., M. Q. Qi, X. Wan, J. Zhao, and Q. Cheng, "Coding metamaterials, digital metamaterials and programmable metamaterials," Light: Science and Applications, Vol. 3, 218, 2014.

80. Liang, L., M. Qi, J. Yang, X. Shen, J. Zhai, W. Xu, B. Jin, W. Liu, Y. Feng, C. Zhang, H. Lu, H.-T. Chen, L. Kang, W. Xu, J. Chen, T. J. Cui, P. Wu, and S. Liu, "Anomalous terahertz reflection and scattering by flexible and conformal coding metamaterials," Advanced Optical Materials, 2015.

81. Gao, L.-H., Q. Cheng, J. Yang, S.-J. Ma, J. Zhao, S. Liu, H.-B. Chen, Q. He, W.-X. Jiang, H.-F. Ma, Q.-Y. Wen, L.-J. Liang, B.-B. Jin, W.-W. Liu, L. Zhou, J.-Q. Yao, P.-H. Wu, and T.-J. Cui, "Broadband diffusion of terahertz waves by multi-bit coding metasurfaces," Light: Science and Applications, Vol. 4, 2015.

82. Liu, S., T. J. Cui, Q. Xu, D. Bao, L. Du, X. Wan, W. X. Tang, C. Ouyang, X. Y. Zhou, H. Yuan, F. H. Ma, W. X. Jiang, J. Han, W. Zhang, and Q. Cheng, "Anisotropic coding metamaterials and their powerful manipulation of differently polarized terahertz waves," Light: Science and Applications, Vol. 5, 2016.

83. Li, F.-F., W. Fang, P. Chen, Y. Poo, and R.-X. Wu, "Transmission and radar cross-section reduction by combining binary coding metasurface and frequency selective surface," Optics Express, Vol. 26, No. 26, 33878-33887, 2018.

84. Saifullah, Y., A. B. Waqas, G.-M. Yang, F. Zhang, and F. Xu, "4-bit optimized coding metasurface for wideband RCS reduction," IEEE Access, Vol. 7, 122378-122386, 2019.

85. Dai, H., Y. Zhao, H. Li, J. Chen, Z. He, and W. Qi, "An ultra-wide band polarization-independent random coding metasurfaces for RCS reduction," Electronics, Vol. 8, No. 10, 2019.

86. Liu, X., J. Gao, L. Xu, Y. Zhao, X. Cao, and S. Li, "A coding diffuse metasurface for RCS reduction," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 724-727, 2016.

87. Yuan, F., G. M. Wang, H. X. Xu, T. Cai, X. J. Zou, and Z. H. Pang, "Broadband RCS reduction based on spiral-coded metasurface," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 3188-3191, 2017.

88. Yang, J. J., Y. Z. Cheng, D. Qi, and R. Z. Gong, "Study of energy scattering relation and RCS reduction characteristic of matrix-type coding metasurface," Applied Sciences, Vol. 8, No. 8, 2018.

89. Jidi, L., X. Cao, Y. Tang, S.Wang, Y. Zhao, and X. Zhu, "A new coding metasurface for wideband RCS reduction," Radio Engineering, Vol. 27, No. 2, 2018.

90. Wu, G., W. Yu, T. Lin, Y. Deng, and J. Liu, "Ultra-wideband RCS reduction based on non-planar coding diffusive metasurface," Materials, Vol. 13, No. 21, 2020.

91. Chen, K., L. Cui, Y. Feng, J. Zhao, T. Jiang, and B. Zhu, "Coding metasurface for broadband microwave scattering reduction with optical transparency," Optics Express, Vol. 25, No. 5, 5571-5579, 2017.

92. Swain, R. and R. K. Mishra, "Phase quantized metasurface supercells for wave manipulation and RCS reduction," Progress In Electromagnetics Research M, Vol. 74, 125-135, 2018.

93. Li, X., M. Feng, J. Wang, Y. Meng, J. Yang, T. Liu, R. Zhu, and S. Qu, "Suppressing edge back-scattering of electromagnetic waves using coding metasurface purfle," Frontier in Physics, 2020.

94. Sheng, L. J., L. S. He, and Y. J. Quan, "Actively tunable terahertz coding metasurfaces," Optics Communications, Vol. 461, 2020.

95. Song, J., X. Wu, C. Huang, J. Yang, C. Ji, C. Zhang, and X. Luo, "Broadband and tunable RCS reduction using high-order re ections and salisbury-type absorption mechanisms," Scientific Reports, Vol. 9, 2019.

96. Liu, S. and T. J. Cui, "Flexible controls of terahertz waves using coding and programmable metasurfaces," IEEE Journal of Selected Topics in Quatum Electronics, Vol. 23, No. 4, 1-12, 2017.

97. Yang, H., X. Cao, F. Yang, J. Gao, S. Xu, M. Li, X. Chen, Y. Zhao, Y. Zheng, and S. Li, "A programmable metasurface with dynamic polarization, scattering and focusing control," Scientific Reports, Vol. 6, 2016.

98. Ma, Q., G. D. Bai, H. B. Jing, C. Yang, L. Li, and T. J. Cui, "Smart metasurface with self-adaptively reprogrammable functions," Light: Science & Applications, Vol. 8, 2019.

99. Zhao, J., X. Yang, J. Y. Dai, Q. Cheng, X. Li, N. H. Di, J. C. Ke, G. D. Bai, S. Liu, and S. Jin, "Programmable time-domain digital-coding metasurface for non-linear harmonic manipualtion and new wireless communication systems," National Science Review, Vol. 6, No. 2, 231-238, 2019.

100. Shaltout, A., A. Kildishev, and V. Shalaev, "Time-varying metasurfaces and Lorentz non-reciprocity," Optical Materials Express, Vol. 5, No. 11, 2459-2467, 2015.

101. Liu, M., A. B. Kozyrev, and I. V. Shadrivov, "Time-varying metasurfaces for broadband spectrral camouflage," Phys. Rev. Applied, Vol. 12, No. 5, 054052-054060, 2019.

102. Stewart, S. A., T. J. Smy, and S. Gupta, "Finite-difference time-domain modeling of space-time-modulated metasurfaces," IEEE Transactions on Antennas and Propagation, Vol. 66, No. 1, 281-292, 2018.

103. Liu, Z., Z. Li, and K. Aydin, "Time-varying metasurfaces based on graphene microribbon arrays," ACS Photonics, Vol. 3, No. 11, 2035-2039, 2016.

104. Salary, M. M., S. J. Zanjani, and H. Mosallaei, "Time-varying metamaterials based on graphene-wrapped microwires: Modeling and potential applications," Phys. Rev. B, Vol. 97, No. 11, 115421-115435, 2018.

105. Wang, X. and C. Caloz, "Spread-spectrum selective camouflaging based on time-modualted metasurface," IEEE Transactions on Antennas and Propagation, Vol. 69, No. 1, 286-295, 2021.

106. Engheta, N., "Thin absorbing screens using metamaterial surfaces," IEEE Antennas and Propagation Society International Symposium, San Antonio, TX, USA, 2002.

107. Mosallaei, H. and K. Sarabandi, "A one-layer ultra-thin meta-surface absorber," IEEE Antennas and Propagation Society International Symposium, Washington, DC, USA, 2005.

108. Yang, J. and Z. Shen, "A thin and broadband absorber using double-square loops," IEEE Antennas and Wireless Propagation Letters, Vol. 6, 388-391, 2007.

109. Landy, N. I., S. Sajuyigbe, J. J. Mock, D. R. Smith, and W. J. Padilla, "Perfect metamaterial absorber," Phys. Rev. Lett., Vol. 100, No. 20, 207402-207406, 2008.

110. Alici, K. B., F. Bilotti, L. Vegni, and E. Ozbay, "Experimental verification of metamaterial based subwavelength microwave absorbers," Journal of Applied Physics, Vol. 108, No. 8, 2010.

111. Assimonis, A. D., T. M. Kollatou, T. V. Yioultsis, and C. S. Antonopoulos, "Absorbing surfaces using EBG structures," IEEE Transactions on Magnetics, Vol. 50, No. 2, 197-200, 2014.

112. Ghosh, S., S. Bahttacharyya, D. Chaurasiya, and K. V. Srivastava, "An ultrawideband ultrathin metamaterial absorber based on circular split rings," IEEE Antennas and Wireless Propagation Letters, Vol. 14, 1172-1175, 2015.

113. Bhattacharyya, S., S. Ghosh, and K. V. Srivastava, "Triple band polarizaion-independent metamaterial absorber with bandwidth enhancement at X-band," Journal of Applied Physics, Vol. 114, No. 9, 2013.

114. Ghosh, S., S. Bhattacharyya, and K. V. Srivastava, "Design, characterisation and fabrication of a broadband polarisation-insensitive multi-layer circuit analogue absorber," IET Microwaves, Antennas & Propagation, Vol. 10, No. 8, 850-855, 2016.

115. Han, Y., L. Zhu, Y. Chang, and B. Li, "Dual-polarized bandpass and band-notched frequency-selective absorbers under multimode resonance," IEEE Transactions on Antennas and Propagation, Vol. 66, No. 12, 7449-7454, 2018.

116. Sharma, A., S. Ghosh, and K. V. Srivastava, "A polarization-insensitive band-notched absorber," IEEE Antennas and Wireless Propagation Letters, Vol. 20, No. 2, 259-263, 2021.

117. Sharma, A., S. Malik, S. Ghosh, and K. V. Srivastava, "A miniaturized band-notched absorber for wideband RCS reduction," 2020 International Symposium on Antennas and Propagation, Osaka, Japan, 2020.

118. Shen, Y., Z. Pei, Y. Pang, J. Wang, A. Zhang, and S. Qu, "An extremely wideband and lightweight metamaterial absorber," Journal of Applied Physics, Vol. 117, No. 22, 2015.

119. Ghosh, S. and K. V. Srivastava, "An equivalent circuit model of FSS-based metamaterial absorber using coupled line theory," IEEE Antennas and Wireless Propagation Letters, Vol. 14, 511-514, 2014.

120. Kundu, D., A. Mohan, and A. Chakrabarty, "Design of a conductive FSS based ultrathin absorber using impedance analysis method of equivalent circuit model," IEEE Indian Conference on Antennas and Propagation, 2018.

121. Hossain, M. I., N. Nguyen-Trong, K. H. Sayidmarie, and A. M. Abbosh, "Equivalent circuit design method for wideband nonmagnetic absorbers at low microwave frequencies," IEEE Transactions on Antennas and Propagation, Vol. 68, No. 12, 8215-8220, 2020.

122. Mishra, R., R. Panwar, and D. Singh, "Equivalent circuit model for the design of frequency-selective, terahertz-band, graphene-based metamaterial absorbers," IEEE Magnetic Letters, Vol. 9, 1-5, 2018.

123. Kern, D. J. and D. H. Werner, "Magnetic loading of EBG AMC ground planes and ultrathin absorbers for improved bandwidth performance and reduced size," Microwave Optical Letters, Vol. 48, No. 12, 2468-2471, 2006.

124. Deng, T., Z.-W. Li, and Z. N. Chen, "Ultrathin broadband absorber using frequency-selective surface and frequency-dispersive magnetic materials," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 11, 5886-5894, 2017.

125. Panwar, R., S. Puthucheri, D. Singh, V. Agarwala, and J. R. Lee, "Microwave absorption properties of FSS-impacted composites as a broadband microwave absorber," Advanced Composite Materials, Vol. 26, No. 2, 99-113, 2016.

126. Sui, S., H. Ma, J. Wang, Y. Pang, M. Feng, Z. Xu, and S. Qu, "Absorptive coding metasurface for further radar cross section reduction," Journal of Physics D: Applied Physics, Vol. 51, No. 6, 2018.

127. Mol, L. V. A. and C. K. Anandan, "An ultrathin microwave metamaterial absorber with enhanced bandwidth and angular stability," Journal of Physics Communication, Vol. 1, No. 1, 2017.

128. Huang, H., Z. Shen, and A. A. Omar, "3-D absorptive frequency selective re ector for antenna radar cross section reduction," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 11, 5908-5917, 2017.

129. Shrekenhamer, D., W.-C. Chen, and W. J. Padilla, "Liquid crystal tunable metamaterial absorber," Physical Review Letters, Vol. 110, 2013.

130. Huang, H. and Z. Shen, "Low-RCS reflectarray with phase controllable absorptive frequency-selective reflector," IEEE Transactions on Antennas and Propagation, Vol. 67, No. 1, 190-198, 2019.

131. Wang, Y., K. Chen, Y. Li, and Q. Cao, "Design of nonresonant metasurfaces for broadband RCS reduction," IEEE Antennas and Wireless Propagation Letters, Vol. 20, No. 3, 346-350, 2021.

132. Koziel, S. and M. Abdullah, "Machine-learning-powered EM-based framework for efficient and reliable design of low scattering metasurfaces," IEEE Transactions on Microwave Theory and Techniques, Vol. 69, No. 4, 2028-2041, 2021.

133. Wong, J. P. S., A. Epstein, and G. V. Eleftheriades, "Reflectionless wide-angle refracting metasurfaces," IEEE Antennas and Wireless Propagation Letters, Vol. 15, 1293-1296, 2015.

134. Fathnan, A. A., T. M. Hossain, D. Mahmudin, Y. N. Wijayanto, and A. D. Powell, "Characterization of broadband focusing microwave metasurfaces at oblique incidence," Applied Physics, 1-9, 2020.

135. Haupt, R. L., "Factors that define the bandwidth of a phased array antenna," 2019 IEEE International Symposium on Phased Array System & Technology (PAST), Waltham, MA, USA, 2019.

136. Shaker, J., M. R. Chacharmir, and J. Ethier, Reflectarray Antennas Analysis, Design, Fabrication, and Measurement, Artech House, 2014.

137. Murugesan, A. R. A. N. J. and K. T. Selvan, "Bandwidth enhancement of RCS reduction checkerboard metasurfaces by mutual coupling mitigation," 2021 International Applied Computational Electromagnetics Society (ACES) Symposium, 2021.

138. Murugesan, A. and K. T. Selvan, "Toward improved prediction of RCS reduction bandwidth of checkerboard metasurfaces," IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, Marina Bay Sands, Singapore, 2021.

139. Xu, G., S. V. Hum, and G. V. Eleftheriades, "Augmented Huygens' metasurfaces employing baffles for precise control of wave transformations," IEEE Transactions on Antennas and Propagation, Vol. 67, No. 11, 6935-6946, 2019.

140. Nadeem, I. and D. Y. Choi, "Study on mutual coupling reduction technique," IEEE Access, Vol. 7, 563-586, 2019.