| In the last few years, the field of telecommunications and especially the one of mobile telephony has evolved rapidly. Cell phones have evolved immensely both in design and function. Due to the development of modern integrated circuit technology, personal communication handsets are shrinking in size and are required to operate at multiple frequency bands for enhanced functionality and performance.;Novel designs of multiband monopole antennas for mobile communication are introduced and analyzed in the Antennas and Propagation Laboratory at Southern Illinois University Carbondale USA. The antennas proposed here are to support both cellular communication and wireless network applications. The target technologies and their frequency bands are Long Term Evolution (LTE),Global System for Mobile Communications(GSM) 850, Digital cellular systems (DCS1800), Personal Communications Service (PCS 1900), Universal Mobile Telecommunications System (UMTS), Wireless Local Area Network (WLAN:2.4--2.483, 5.15--5.35, and 5.725--5.85 GHz) and Worldwide Interoperability for Microwave Access (WiMAX: 2.5--2.69,3.3--3.8, and 5.25--5.85 GHz).;The proposed antennas are printed on a single dielectric substrate and are fed by a 50 Ω microstrip line. Multiband and wideband performance is achieved by incorporating slots of optimum geometry at suitable location on the radiating patch, and on the ground plane of these antennas. Designed antennas satisfy the condition of dB magnitude of reflection scattering parameter S11 less than-10 dB over the frequency band covering WLAN and WiMAX while simultaneously maintaining a gain greater than 0dBi. For the lower cellular bands of LTE, GSM 850,-6dB impedance bandwidth with the gain as low as -5dBi is acceptable for practical applications, this standard has been met by all antennas presented in this dissertations. |
