A Bidirectional Bent Vivaldi-Connected Array With Short-Circuited Branches for UWB Pulse Radiation

A Vivaldi-connected array based on the infinite current sheet is proposed, which avoids short-circuited resonance points brought by reflecting ground by using a directional Vivaldi antenna instead of an omnidirectional dipole antenna. The bidirectional bent construction of the radiating arms combines with metamaterial matching layer is designed to improve impedance matching performance and reduce the antenna profile. In order to further expand the bandwidth, the short-circuited branches are constructed to eliminate the common mode resonances. The final design of the bidirectional bent Vivaldi-connected array has an impedance bandwidth of around 0.6–6 GHz with unit dimensions of $2.5\times 2.5\times 4.5$ cm. An $8\times 4$ array was processed and tested in the frequency and time domains, and the measured results were consistent with the simulation.