A probe station based setup for on-wafer antenna measurements is presented. The setup allows for measurement of return loss and radiation patterns of an on-wafer antenna-hence-forth referred to as ...the antenna under test (AUT), radiating at broadside and fed through a coplanar waveguide (CPW). It eliminates the need for wafer dicing and custom-built test fixtures with coaxial connectors or waveguide flanges by contacting the AUT with a coplanar microwave probe. In addition, the AUT is probed exactly where it will be connected to a transceiver IC later on, obviating de-embedding of the measured data. Sources of measurement errors are related to calibration, insufficient dynamic range, misalignment, forward scattering from nearby objects, and vibrations. The performance of the setup is demonstrated from 2 to 40 GHz through measurement of an on-wafer electrically small slot antenna (lambda 0 /35 times lambda 0 /35,3.5 times 3.5 mm 2 ) radiating at 2.45 GHz and an aperture coupled microstrip antenna (2.4 times 1.7 mm 2 ) radiating at 38 GHz.
The radiation resistance of a short planar monopole antenna with a small ground plane is studied. The monopole of length h (λ/100 <; h <; λ/10) is located orthogonally to the edge of a rectangular ...ground plane of length L and width W . First, a parametric study is realized in order to determine the effect of the ground plane dimensions on the radiation resistance. Then, the two limit configurations, long and wide, are studied analytically with a model based on triangular current distributions, and comparisons to numerical results are shown. Finally, impedance matching by addition of one or two dipole arms is studied. We explain why this addition, besides reactance compensation, further increases the radiation resistance.
An active dipole antenna is in operation since five years at the Nançay radio Observatory (France) in the CODALEMA experiment. A new version of this active antenna has been developed, whose shape ...gave its name of “Butterfly” antenna. Compared to the previous version, this new antenna has been designed to be more efficient at low frequencies, which could permit the detection of atmospheric showers at large distances. Despite a size of only 2
m×1
m in each polarization, its sensitivity is excellent in the 30–80
MHz bandwidth. Three antennas in dual polarization were installed on the CODALEMA experiment, and four other have been recently installed on the Auger area in the scope of the AERA project. The main characteristics of the Butterfly antenna are detailed with an emphasis on its key features which make it a good candidate for the low frequency radioastronomy and the radio detection of transients induced by high energy cosmic rays.
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