Wideband Dipole Array with Balanced Wideband Impedance Transformer (BWIT) Article

Johnson, AD, Zhong, J, Livadaru, M et al. (2021). Wideband Dipole Array with Balanced Wideband Impedance Transformer (BWIT) . 2 163-169. 10.1109/OJAP.2020.3044471



cited authors

  • Johnson, AD; Zhong, J; Livadaru, M; Venkatakrishnan, SB; Alwan, EA; Volakis, JL

abstract

  • Within the context of modern digital phased array (DPA) radios, differential Radio Frequency (RF) front-ends provide much greater immunity to noise and distortion by suppressing second order harmonics. Recent advancements in differential RF front-ends offer high dynamic range, high linearity, and low noise in the transceiver chain. However, a major roadblock to fully differential systems is the presence of common-mode resonances. In this article, we present a novel wideband differential feed for dipole arrays that overcomes this bottleneck. Our dipole array is developed for the L-S band (viz. 1.05 GHz to 3.2 GHz) with emphasis on dual-linear polarization and resonance-free scanning to low angles. The novelty of this article is the Balanced Wideband Impedance Transformer (BWIT) feed that mitigates common-mode currents across the entire band while scanning to low angles. Array simulations are verified with measurements of an 8× 8 prototype in a volume of 384mm × 384 mm × 57 mm. The array achieves resonance-free scanning across a 3:1 impedance bandwidth with VSWR < 3 for the cases of θ = 0(Broadside), 45° (D-plane), 60° (E-plane) and across a 2.37:1 impedance bandwidth with VSWR < 3 for the case of 45° (H-plane). Measured gain achieves near-theoretical values across the operating band.

publication date

  • January 1, 2021

Digital Object Identifier (DOI)

start page

  • 163

end page

  • 169

volume

  • 2