Integrated antennas for terahertz circuits

The alliance of monolithic device technology and printed-circuit antennas has opened an unlimited number of possibilities for both antenna and system designer. Technology has been developed for up to 90 GHz systems, but higher operating frequencies for new communication systems are coming fast, and research is even moving towards the 1 THz region. In this submillimetre-wave region, the limitation of integrated antennas is the availability of compatible planar detectors. High-efficiency integrated antennas would result in planar receivers with comparable performance to the best waveguide system at a fraction of the cost. A combination of different permittivities on the same substrate, say small islands of high dielectric constant material on a low dielectric constant substrate, could be an important option to overcome the diverse problems encountered when trying to integrate microstrip antennas with active circuits