Printed penta-band laptop computer antenna for WWAN operation

In this paper we demonstrate a new printed penta-band laptop computer antenna. The proposed design is composed of a 0.25¿ loop antenna in parallel with a 0.125¿ monopole antenna. The loop antenna is fed by a printed matching circuit and the monopole antenna is fed by a chip inductor as its matching circuit. With these feeding network, 0.25, 0.5 and 1.0¿ modes of loop antenna can be excited and the 0.125¿ mode of monopole antenna can also be excited. The 0.25¿ mode of loop and 0.125¿ mode of monopole form a wide bandwidth for lower band where the 0.5 and 1.0¿ modes of loop form a wide bandwidth for upper band of WWAN operation. The lower band covers from 824~1078 MHz for GSM850/900 operation and the upper band covers from 1650~2170 MHz for GSM1800/1900/UMTS operation. The proposed design is of a planar structure printed on an FR4 substrate which is promising for practical application.