A Flat and Thin Wideband Antenna with Band-Notch and Monopole-like Radiation Characteristics

A low profile wideband circular patch antenna with monopole-like radiation patterns and band-notch characteristics is presented. The proposed antenna covers from 3.8 to 9.3 GHz with a band rejection in 5 to 6.2 GHz. This is achieved by loading the antenna with two rectangular slots and two parasitic rings. By combination of two modes of TM
₀₁
and TM
₀₂
, the monopole-like radiation patterns are achieved over the entire bandwidth. The profile of the proposed planar antenna is only 0.04λ
_min
height.