An important component of any wireless system is its antenna. With recent advances in solid state devices and MEMS technology, construction of high performance miniaturized transmit and receive modules have become realizable. These modules together with miniaturized sensors and transducers have found numerous applications in industry, medicine, and military. In addition to the need for antenna miniaturization, low power characteristics of such transmitters and receivers are extremely important as well. Whereas significant efforts have been devoted towards achieving low power and miniaturized electronic and RF components, issues related to design and fabrication of efficient, miniaturized, and easily integrable antennas have been overlooked. The early studies of small antennas were restricted to the establishment of fundamental limitations of these types of antennas with regard to the antenna size and bandwidth [1-2]. In recent years, practical aspect of antenna miniaturization hat received a significant attention. Most successful designs, however, rely on the use of high Permittivity ceramics, which are not suitable for monolithic integration. Recently, the concept of a new class of miniaturized, planar, re-configurable antennas, which takes advantage of antenna topology for miniaturization, was demonstrated [3-4]. Using this concept, design of a miniaturized antenna as small as 0.05λ{sub}0× 0.05λ{sub}0 and a fairly high efficiency of -3dBi was demonstrated. Since there are neither polarization nor mismatch losses, the antenna efficiency is limited only by the dielectric and Ohmic losses of the substrate on which the antenna is made. The bandwidth of this antenna is rather small as it is the case for all miniaturized antennas. Resonant antennas in general, and slot-dipoles in particular are inherently narrow-band. By reducing the size of a slot, the physical aperture of the antenna is reduced and therefore, the radiation conductance of miniaturized slot antenna becomes very small. On the other hand, an infinitesimal dipole can have an effective aperture, which is as high as that of a half wavelength dipole under the impedance matched condition. One way to match the impedance of the miniaturized slot antenna is to tune it slightly off resonance, whether capacitively, or inductively. A smaller capacitance or larger inductance is needed depending on whether the antenna is tuned below or above the resonance. However, a smaller capacitance, or conversely a larger inductance, results in a narrower bandwidth. To partially improve the bandwidth of the miniaturized slot antenna, one can increase the physical aperture without increasing the overall size of the antenna.
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