A Study on Ultra-short Wave Band TCDA Based on Marchand Balun

In order to meet the requirements of "The Twelfth Five Year Plan" dual super antennas for ultra-wideband, over the horizon, low profile, and wide-angle scanning, a tightly coupled dipole array antenna (TCDA) operating in the 110 MHz~520 MHz frequency band is designed in this paper. The array antenna consists of 8×8 elements, using a combination of second-order Wilkinson power divider and integrated Marchand Balun to achieve ultra-wideband, balanced feeding, and impedance matching functions, collectively forming a feeding network. Additionally, the structure of dual-dipole unit is adopted to suppress E-plane scanning common-mode resonance, and H-plane scanning impedance matching is achieved by loading a vertical frequency selective surface layer. The simulation and measurement results show that the typical voltage standing wave ratio of the antenna is less than 2.5 within ±40°scan angle and 110 MHz~520 MHz band. Moreover, the array antenna gain is 16.2 dB at 520 MHz, and the overall profile height of the antenna is less than λ_low/8. The designed ultra-short wave band TCDA has the advantages of ultra-wideband, wide-angle scanning, low profile, and easy integration, which fills the gap in TCDA design at the very high frequency and the ultra-high frequency bands both at home and abroad.