Publication: IEICE TRANSACTIONS on Electronics Publication Date: 1997/06/25 Vol. E80-CNo. 6pp. 794-799 Type of Manuscript: Special Section PAPER (Special Issue on Microwave and Millimeterwave High-power Devices) Category: Keyword: GaAs, direct-conversion, attenuator, modulator, MMIC, MESFET, personal handy phone system,