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In this paper, a design approach for getting dual-band working in a Wilkinson-based power divider (WPD) without adding any reactive elements or open- or short-circuited stubs is presented. The transfer matrix approach is used to get the analytical solutions of the required design equations. Admittance representation with respect to the input and output ports is done to perform even-odd mode analysis. In this impedance of each section is kept constant but the electrical length varies. Different combinations of electrical lengths are taken such that the overall length remains constant. The electrical lengths are selected based on dual-band analysis and depend on the tuning ratio. The conditions for attaining the impedance matching are applied to the obtained design equations and hence found out the values of the matching resistors to be placed between the transmission line sections. The proposed power divider centered at 2.5GHz and 7GHz is theoretically calculated simulated and fabricated. Finally, design procedures and experiments show good agreement with theoretical simulation.

Main objective of wireless communication system is the design of wideband, multiband low profile small antenna. A fractal antenna effectively utilizes the available space within a sphere of radius "r" which improves the bandwidth of the antenna enclosed in the sphere [2]. The term fractal refers to miniaturized structure which stands for irregular or broken pieces. Several natural phenomenons like trees, mountains etc. shows fractal nature. The fractal concepts are used in antenna theory and design and there are many studies and implementation of fractal antenna elements and arrays. This paper brings a comparison of different shrinking methods on antenna size based on fractal geometry while maintaining performance parameters. This paper presents a survey on fractal antennas designed with different geometric structures, its iteration process, radiation parameters etc. Which are used for wireless applications.