A novel integrated antenna for millimeter-wave personal communications systems

This paper presents the design and experimental results of a coplanar waveg uide (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 (epsilon(r) = 9.9), which is close to the dielectric constant of GaAs and demonstrates the feasibility of inte gration of such an antenna structure into monolithic circuits. The major ad vantage of this configuration is that the reverse side of the antenna can b e used for the active and feed components, The antenna structure combines t he advantages of CPW with the those of the aperture-coupled microstrip ante nna and simplifies the structure of the antenna by reducing the number of m etallization level, from three down to two. In addition, this type of coupl ing is advantageous when applied to millimeter-wave monolithic phased array s. A unique feed design eliminates the competition for surface space betwee n the antenna elements and the feed network. In addition, the ground plane shields the antenna half-space from spurious radiation emitted by feed line s and active devices. Finally, aperture coupling avoids problems associated with probe feeds at millimeter-wave frequencies, such as complexity of con struction and large probe self reactances. This new type of antenna opens t he ways to a large number of a new possibilities such as active antennas Fo r millimeter-wave personal communications using monolithic microwave integr ated circuits (MMIC's) on the same substrate and a combination of optical a nd radio transmission.