A novel integrated antenna for millimeter-wave personal communications systems

Presents the design and experimental results of a coplanar waveguide (CPW) aperture-coupled patch antenna for the extremely high frequency (EHF) band around a center frequency of 37 GHz. The antenna is implemented on a high dielectric constant substrate (/spl epsiv//sub r/=9.9), which is close to the dielectric constant of GaAs and demonstrates the feasibility of integration of such an antenna structure into monolithic circuits. The major advantage of this configuration is that the reverse side of the antenna can be used for the active and feed components. The antenna structure combines the advantages of a CPW with those of the aperture-coupled microstrip antenna and simplifies the structure of the antenna by reducing the number of metallization levels, from three down to two. In addition, this type of coupling is advantageous when applied to millimeter-wave monolithic phased arrays. A unique feed design eliminates the competition for a surface space between the antenna elements and the feed network. In addition, the ground plane shields the antenna half-space from spurious radiation emitted by feed lines and active devices. Finally, aperture coupling avoids problems associated with probe feeds at millimeter-wave frequencies, such as complexity of construction and large probe self reactances. This new type of antenna opens ways to a large number of a new possibilities such as active antennas for millimeter-wave personal communications using monolithic microwave integrated circuits (MMICs) on the same substrate and a combination of optical and radio transmission.