Directly Connected Linear Antenna Array With Band-Notch Characteristics for UWB Applications

This letter proposes a directly connected linear antenna array for ultrawideband applications. First, a wideband antenna element based on multimode resonances is proposed. To facilitate direct connection for small array sizes, the mutual coupling between adjacent elements is reduced. Additionally, an extra slot mode is introduced to achieve both band notch property and antenna miniaturization simultaneously. To combat the edge effect of this antenna array, only slight geometry adjustments of periphery elements are required. Finally, to verify the proposed concept, a 1 x 4 array prototype is fabricated and measured. The experimental results are consistent with the simulation ones, obtaining a wide bandwidth of 117% and gain over 10 dBi. Additionally, a band notch at 3.5 GHz with a gain drop to -3.7 dBi is realized.