An array of printed dipoles at 60 GHz

An array of four printed dipole antennas is developed at 60GHz for Image-based chipless RFID application. The dipoles are built on both sides of the Takonic TLX-8 (ε_r=2.55) and fed through a Co-planar waveguide (CPW) line. The total array dimension including its long feed line is 24×14 mm. An excellent wide radiation pattern in the azimuth direction is tested. The measured gain of the array is between 5.5 and 7 dBi over the frequency range of 57-64 GHz and the cross-polarization ratio is less than -18dB. The printable structure, wide radiation pattern, low return loss, wide bandwidth and high cross-polarization ratio of the proposed array suggest it as a suitable antenna for many applications in mm-wave range including chipless RFID systems.