Novel compact antenna designs for WiMAX (Worldwide interoperability for microwave access) operation in the mobile phone are presented in this thesis. In the first design, the antenna is integrated at one corner of system circuit board of the mobile phone and consists of two radiating portions; the monopole slot is formed by integrating the two portions. In the second design, two different antenna structures are used to achieve all WiMAX operating bands. Finally, in the third design, the chip antenna comprises a resonant monopole patch, a resonant shorter slot and a matching longer slot. The latter two slots are embedded within the monopole patch to achieve a compact integration. Detailed antenna designs and experimental results are presented and discussed.

Two novel internal WWAN antennas having multi-band operation capability and suitable to be embedded in the laptop computers are proposed. The first antenna is a penta-band printed monopole slot antenna, which can cover GSM850/900/1800/1900/UMTS operation. The second antenna is a penta-band printed dual-loop antenna. The antenna can cover GSM850/900/1800/1900/UMTS operation and occupies a small size. The effects of the environment and the user¡¦s hand on the internal laptop computer antenna are also studied. Take the first antenna as an example; the obtained results show that the effects of the internal environment of the laptop computer are mostly on the antenna¡¦s impedance matching, which however can be improved by adjusting the parameters of the antenna. On the other hand, since the user¡¦s hands are lossy materials, a decrease in the antenna¡¦s radiation efficiency is observed when the user¡¦s hand is in the vicinity of the internal antenna.