DESIGN OF FOLDED PLANAR MONOPOLE INTERNAL ANTENNA FOR MULTI-BAND MOBILE PHONE

摘要

A folded monopole built-in antenna for a multiband mobile communications terminal is provided to improve wideband characteristic and radiation property with simple structure and cover current common service bands including CDMA(824-894MHz), GSM(880-960 MHz), GPS(1575±5 MHz), DCS(1710-1880 MHz), USPCS(1850-1990 MHz), W-CDMA(1920-2170 MHz), 2.4 GHz band Bluetooth and WLAN, S-DMB(2630-2655 MHz) and 5.2/5.8GHz WLAN(5200-5800 MHz). A radiator(20) bends a metal plate toward a horizontal axis(x) and is formed. The radiator comprises: a first horizontal plate(ABCD) including a feeding point(C); a first vertical plate(CDEF) for formation of a lower resonant layer of a printed circuit board(10); a second vertical plate(GHIJ) for formation of a top resonant layer; a second horizontal plate(EFGH) connected to two vertical plates; and a third horizontal plate(IJKL) formed on the top of the first horizontal plate. A ground plane(30) is formed on the printed circuit board.