The current status of millimeter-wave communication systems

It is noted that the availability of mature low-cost integration procedures, i.e. hybrid and monolithic integration techniques, as well as progress in solid-state source technology has put emphasis on commercial millimeter-wave applications. Digital distribution radios for telephone network enlargements and various video services are becoming more and more important. About 700 short-range millimeter-wave radio links are already installed in Japan alone. The various design approaches to meet stringent cost requirements as well as corresponding technical data of Japanese and European millimeter-wave research and prototype communication systems are reviewed. The Japanese approach of using doubler or quadrupler circuits to achieve transmission frequencies in the 50-GHz range takes advantage of well-established integration technologies at lower micro/millimeter-wave frequencies, while the European approach uses newly developed millimeter-wave integration techniques such as finline