Ultra wide-band slot antenna based on liquid crystal polymer material for millimeter wave application

A millimeter wave ultra-wide band (UWB) tapered slot antenna is presented based on a multilayer liquid crystal polymer (LCP) circuit process. The multilayer circuit board consists of eight copper layers and seven LCP layers. In order to enhancing the bandwidth, two overlapped tapered slots with different flare angle are applied in the 3^rd and the 5^th copper layers, respectively. A low backward radiation characteristic is achieved due to using the ground-backed structure. A simple design guideline is detected and the dimension is optimized. The designed results indicate that the millimeter wave UWB slot antenna can work in the frequency band of 33GHz-60GHz (a relative bandwidth of 58%). The radiation patterns are calculated at three typical frequencies and the analysis demonstrates that an elliptical polarization performance is obtained within the total operation frequency band. The study also demonstrates that the LCP process is suitable for developing lightweight and high performance millimeter wave antennas.