The development of wireless indoor communication in the millimeter-wave domain (60 GHz) requires antenna arrays with specific performances. Microstrip technology is attractive at these frequencies if one uses material with weak losses and a low-cost technology. Glass Teflon, alias RT/D Duroid 5880, or polymethyl–pentene, alias TPX, are good candidates. But spurious radiation due to the feeding network often occurs in the millimeter band. These effects often increase the cross-polarization component and the sidelobe level. A solution to reduce these problems is to use slot-coupled printed antenna arrays, with radiating elements that are separated from the feeding lines by the ground plane. Various types of patterns have been investigated, either directive or, on the contrary, with a large sector beam. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 28: 105–108, 2001.