Compact Uniform Circular Quarter-Wavelength Monopole Antenna Arrays With Wideband Decoupling and Matching Networks

Two novel decoupling and matching networks (DMNs) in microstrip technology for three-element uniform circular arrays (UCAs) are investigated compared to a more conventional DMN approach with simple neutralization lines. The array elements coaxially-fed quarter-wavelength monopole antennas over finite groundplane. Three-element considered since UCAs an odd number of able provide almost constant maximum factor the whole azimuthal angular range. new designs explained from theoretical point view their implementations four- three-elements without terms bandwidth as well beamforming capabilities. In addition excellent below -16 dB, broader is obtained by two DMNs. reasons enhanced similar both cases: By introducing several circuit offering additional degrees freedom, input impedances at different frequencies becomes feasible. One presented offers larger bandwidth, while other design better total efficiency. Scattering parameters, radiation patterns, capabilities, gain all verified measurements operating bandwidth.