This paper introduces a novel technique to enhance the gain of the basic monopole antenna by using broadband gradient refractive index (GRIN) metamaterial. The proposed GRIN is designed by using a parallel-line unit cell metamaterial with different refractive index. A seven GRIN lens is placed on the omnidirectional printed basic monopole antenna. perpendicularly. https://www.foldlyers.shop/product-category/books/