Editing Radar cross section (section)

===Redirecting scattered energy without shaping===
This technique is relatively new compared to other techniques chiefly after the invention of [[Electromagnetic metasurface|metasurfaces]].<ref name="A. Modi 19 2">A. Y. Modi; M. A. Alyahya; C. A. Balanis; C. R. Birtcher, "Metasurface-Based Method for Broadband RCS Reduction of Dihedral Corner Reflectors with Multiple Bounces," in IEEE Transactions on Antennas and Propagation, vol.67, no.12, pp. -, Dec. 2019. {{doi| 10.1109/TAP.2019.2940494}}</ref><ref name="A. Modi 19">A. Y. Modi; C. A. Balanis; C. R. Birtcher; H. Shaman, "New Class of RCS-Reduction Metasurfaces Based on Scattering Cancellation Using Array Theory," in IEEE Transactions on Antennas and Propagation, vol. 67, no. 1, pp. 298-308, Jan. 2019. {{doi| 10.1109/TAP.2018.2878641}}</ref><ref name="A. Modi 17">A. Y. Modi; C. A. Balanis; C. R. Birtcher; H. Shaman, "Novel Design of Ultra-Broadband Radar Cross Section Reduction Surfaces using Artificial Magnetic Conductors," in IEEE Transactions on Antennas and Propagation, vol. 65, no. 10, pp. 5406-5417, Oct. 2017. {{doi| 10.1109/TAP.2017.2734069}}</ref> As mentioned earlier, the primary objective in geometry alteration is to redirect scattered waves away from the backscattered direction (or the source). However, it may compromise performance in terms of aerodynamics.<ref name="A. Modi 19 2"/><ref name="A. Modi 19"/><ref>Appl. Phys. Lett. 104, 221110 (2014). {{doi| 10.1063/1.4881935}}</ref> One feasible solution, which has extensively been explored in recent time, is to utilize metasurfaces which can redirect scattered waves without altering the geometry of the target.<ref name="A. Modi 19"/><ref name="A. Modi 17"/> Such metasurfaces can primarily be classified in two categories: (i) Checkerboard metasurfaces, (ii) Gradient index metasurfaces.