Millimeter-wave antennas on a LTCC cavity

This paper discussed a millimeter-wave dipole antenna on a LTCC board. The dipole is fed with a microstrip line back by a ground patch serving as a reflector. 10dB end-fire antenna gain is obtained. The LTCC board acts as a dielectric cavity enhancing end-fire gain. It is found that antenna placement affected significantly the end-fire gain, which can be explained by radiation discontinuity on the endfire direction. Off-center antenna placement results in beam tilting away from the end-fire, due to two cross-over cavity modes. The best results were found for the case when the dipole is centered and at least 1 wave-guided length from the radiation discontinuity.