Text this: Gain improvement for rectangular horn antenna by using curved-woodpile metamaterial

 _    _      ___     __   _     ______    _____   
| || | ||   / _ \\  | || | ||  /_   _//  / ____|| 
| || | ||  | / \ || | '--' ||   -| ||-  / //---`' 
| \\_/ ||  | \_/ || | .--. ||   _| ||_  \ \\___   
 \____//    \___//  |_|| |_||  /_____//  \_____|| 
  `---`     `---`   `-`  `-`   `-----`    `----`