FOR RECEIVER AND TRANSMITTER front ends in the millimeter-wave range to be widely used, certain problems must be resolved. An example is the connection of a miniature millimeterwave, monolithic integrated-circuit chip to an external antenna. To address this issue, Andreas Patrovsky and Ke Wu from the Poly-Grames Research Center at Ecole Polytechnique (Montreal, Quebec, Canada) developed a linear-array antenna fed by substrate integrated image guide (SIIG) at 94 GHz.

The resulting design provides a wide tuning range for the radiation coefficient and superior linear polarization purity. In addition, a reflection-compensation technique reduces the overall return loss while permitting frequency scanning through broadside direction without suffering from a stop band due to distributed Bragg reflection. The 2-cm-long implementation produced a fan beam with 11 dB of gain. See "Substrate Integrated Image Guide Array Antenna for the Upper Millimeter-Wave Spectrum," IEEE Transactions on Antennas and Propagation, Nov. 2007, p. 2994.