Thu, 24 Jul 2008 23:16:01 BST CiteULike: dcastros Ghafouri-Shiraz http://www.citeulike.org/user/dcastro/author/Ghafouri-Shiraz CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dcastro/article/2782051 <i>Antennas and Propagation, IEEE Transactions on, Vol. 51, No. 4. (2003), pp. 722-729.</i><br /><br />This paper proposes two novel designs of a multiband antenna using multiple rings. The first design consists of a set of self-similar circular rings. This is an alternative to the recently reported triangular fractal Sierpinski gasket monopole antenna, and comparison is made to this and the circular disk monopole antenna. The second design is realized by varying the shape of the circular structure to an elliptical one. Larger bandwidth and improved patterns are achieved. In comparison to the circular disk, improved radiation pattern control at higher operating bands, due to the discrete structure of the multiple rings, is shown by numerical and experimental results. The bandwidth is significantly larger than the Fractal Sierpinski gasket and Parany monopole. Multiband multiple ring monopole antennas CTP Song PS Hall H Ghafouri-Shiraz doi:10.1109/TAP.2003.811097 Antennas and Propagation, IEEE Transactions on, Vol. 51, No. 4. (2003), pp. 722-729. 2008-05-09T23:56:12-00:00 2003 Antennas and Propagation, IEEE Transactions on 51 4 722 729 antenna multiband http://www.citeulike.org/user/dcastro/article/2776279 <i>Microwaves, Antennas and Propagation, IEE Proceedings -, Vol. 150, No. 4. (2003), pp. 290-294.</i><br /><br />Two methods for achieving a complete RF front end equipped with its radiator within a single chip package are presented. This packaging technique, which uses a parasitic radiator, provides an alternative solution to problems associated with reduced size electrically small antennas, such as restoration of the antenna gain to 6 dBi and increasing its bandwidth to over 4%. Several parasite configurations have been described and sensitivity of the overall antenna performance to coupling height, parasite dimension, and position with respect to the feed antenna have been assessed. Circular polarisation of such a configuration using a truncated square parasite has also been demonstrated. Novel RF front end antenna package PCT Song PS Hall H Ghafouri-Shiraz doi:10.1049/ip-map:20030414 Microwaves, Antennas and Propagation, IEE Proceedings -, Vol. 150, No. 4. (2003), pp. 290-294. 2008-05-09T16:41:52-00:00 2003 Microwaves, Antennas and Propagation, IEE Proceedings - 150 4 290 294 antenna front-end rf http://www.citeulike.org/user/dcastro/article/2776060 <i>Microwave and Millimeter Wave Technology, 2002. Proceedings. ICMMT 2002. 2002 3rd International Conference on (2002), pp. 618-621.</i><br /><br />In this paper, a non-linear circuit model of a FET has been incorporated into the finite-difference time-domain (FDTD) method when microwave active antennas are analysed. The FET, operating in class A mode, is biased and its non-linear properties (second harmonics) are investigated in a patch antenna configuration. The algorithm and the simulation results will be useful in the development of high power integrated active antenna modules. FDTD analysis of microwave active antenna including nonlinear model of FET transistor Y Zhang P Gardner H Ghafouri-Shiraz PS Hall Microwave and Millimeter Wave Technology, 2002. Proceedings. ICMMT 2002. 2002 3rd International Conference on (2002), pp. 618-621. 2008-05-09T14:56:17-00:00 2002 Microwave and Millimeter Wave Technology, 2002. Proceedings. ICMMT 2002. 2002 3rd International Conference on 618 621 active analysis antenna fdtd fet microwave model nonlinear http://www.citeulike.org/user/dcastro/article/2774771 <i>Microwaves, Antennas and Propagation, IEE Proceedings -, Vol. 145, No. 4. (1998), pp. 313-320.</i><br /><br />Active antenna oscillator arrays have been considered in millimetre-wave communication systems to increase the power levels for low cost radio modules, and in radar systems for high power generation. The authors have investigated the performance of active antenna oscillator arrays, particularly the data-rate limitations, the modulation effects on the radiation pattern, and the bit error rate performance of these arrays, in practical applications. Also, a closed-form solution for the phase dynamics of a single injection-locked oscillator has been derived Performance of active antenna oscillator arrays under modulation for communication systems C Kykkotis PS Hall H Ghafouri-Shiraz Microwaves, Antennas and Propagation, IEE Proceedings -, Vol. 145, No. 4. (1998), pp. 313-320. 2008-05-09T08:36:03-00:00 1998 Microwaves, Antennas and Propagation, IEE Proceedings - 145 4 313 320 active antenna array oscillator http://www.citeulike.org/user/dcastro/article/2774606 <i>Microwave Symposium Digest, 1997., IEEE MTT-S International, Vol. 2 (1997), pp. 591-594 vol.2.</i><br /><br />Active antenna oscillator arrays have been considered in millimetre-wave communication systems for increased power levels in low cost radio modules. In this paper, we have investigated the data-rate limitations, the modulation effects on the radiation pattern, and the bit error rate performance of antenna oscillator arrays in practical applications Active antenna oscillator arrays in communication systems C Kykkotis PS Hall H Ghafouri-Shiraz doi:10.1109/MWSYM.1997.602862 Microwave Symposium Digest, 1997., IEEE MTT-S International, Vol. 2 (1997), pp. 591-594 vol.2. 2008-05-09T07:25:59-00:00 1997 Microwave Symposium Digest, 1997., IEEE MTT-S International 2 591 594 vol.2 active antenna array oscillator