Circularly polarized transmitarray with sequential rotation in Ka-band
Résumé
We present here the design and demonstration of a circularly polarized (CP) transmitarray antenna operating in Ka-band and illuminated by a linearly polarized (LP) source. The proposed design is based on a CP unit-cell with simulated insertion loss of 0.2 dB at 30 GHz. In order to improve the axial ratio (AR) bandwidth, the sequential rotation technique is applied to the full array configuration. A model based on a hybrid in-house simulation tool is also proposed to predict accurately the array performance. The realized prototype, formed by 400 unit-cells, has 1 bit of phase resolution. The measured broadside gain is 22.8 dBi at 30 GHz with a 3-dB bandwidth of 20% in right-handed CP (RHCP). The obtained 3-dB AR bandwidth of 24.4% is comparable with higher resolution designs
Mots clés
antenna radiation patterns
Arrays
axial ratio bandwidth
Bandwidth
circularly polarized transmitarray antenna
circular polarization
Circular polarization (CP)
CP unit cell
discrete lens
electromagnetic wave polarisation
frequency 30 GHz
full array configuration
Gain
Gain measurement
hybrid in-house simulation tool
Insertion loss
Ka band
linearly polarized source
loss 0.2 dB
microwave antenna arrays
millimetre wave antenna arrays
right-handed CP
sequential rotation
transmitarray
Transmitting antennas
word length 1 bit