This paper presents an AMC reflector backed low-profile annular slot-antenna with unidirectional radiation operating at the L band (1-2 GHz). The proposed antenna comprises of an FR4 substrate with a square shaped annular slot on one side and a feed element on the other side. The intrinsically bidirectional radiation of the slot antenna is made unidirectional by backing it with an AMC surface. A close separation of ~0.1 λo between annular slot radiator and AMC reflector surface is achieved.
