This paper describes the design and construction of a BAR-mode high-efficie
ncy active transmitting patch antenna (HEAP). The dimensions, shape, and lo
cation of the feeding point in the antenna are chosen to obtain an input im
pedance so the transistor works in the BAR mode at 1650 MHz with high colle
ctor efficiency and low bias voltage. A HEAP antenna with an efficiency of
about 60%, V-cc = 3 V, and EIRP = 2.5 W has been developed. (C) 2001 John W
iley & Sons, Inc.