Holographic mmW-Antennas With ${\rm TE}_0$ and ${\rm TM}_0$ Surface Wave Launchers for Frequency-Scanning FMCW-Radars

This paper presents three different kinds of planar holographic antennas optimized for the usage in frequency-modulated-continuous-wave (FMCW)-radar systems. The antennas use different kinds of surface-wave modes (TE- and TM-modes), created by planar surface-wave launchers. Due to these feeds the antennas are very well suited for integration into millimeter-wave-systems. The radiation performance is calculated on the basis of holographic theory and the results are verified by full-wave simulations and measurements. Bidirectional radiation of the TE
₀
-antennas is avoided by using artificial-magnetic-conductor (AMC) structures as antenna reflectors. This novel approach allows a holographic antenna with great integration qualifications and a highly directive and frequency-scanning main lobe and is compared with the also unidirectional TM
₀
-mode antenna.