An Ultrathin Low-Profile Tightly Coupled Dipole Array Fed by Compact Zigzagging Baluns

Abstract

In this paper, we propose for the first time a novel feed approach to a tightly coupled dipole array (TCDA). Firstly, compact zigzagging microstrip feedlines are utilized as baluns to feed our array elements to obtain wideband impedance-matching characteristics. Secondly, this array is designed on ultrathin substrates aiming at obtaining ultra-tight coupling between the dipole arms of two neighboring elements. Some irreplaceable parasitic pads are developed and added to the radiating arms to improve both the impedance and radiation characteristics of the TCDA. With these technologies, a 12 × 12 TCDA prototype is designed, fabricated and measured for verification. The array achieves an impressive impedance bandwidth spanning of 4–18 GHz for S11<−10 dB. Its radiation patterns and realized gain are measured to verify its stable electromagnetic characteristics. Its realized gain is from 15 dB to 25 dB within the operating frequency band. Its efficiency is around 91%. Its measured results show good agreement with simulations.

Broadband Beam-Scanning Phased Array Based on Microwave Photonics

“…In recent years, with the increasing demand for beam-scanning antennas, phased array antennas have also been used in wireless communication, and the operating frequency of such antennas has been extended from the microwave to the millimeter-wave band [7][8][9][10]. Various forms of phased array antennas have been proposed, such as ultra-wideband phased array antennas [11][12][13][14], metasurface antennas [15][16][17][18][19], and digital phased array antennas [20]. At the same time, different technologies have been investigated to enhance the performance of phased arrays, such as optimization algorithms [21][22][23][24], conformal technology [25], directional modulation technology [26], and wide-scanning technology [5,[27][28][29][30].…”