Abstract-The multiband behavior of the fractal Sierpinski antenna is described in this paper. Due to its mainly triangular shape, the antenna is compared to the well-known single-band bow-tie antenna. Both experimental and numerical results show that the self-similarity properties of the fractal shape are translated into its electromagnetic behavior. A deeper physical insight on such a behavior is achieved by means of the computed current densities over the antenna surface, which also display some similarity properties through the bands.

Experimental and computed results show a multiband behaviour over five bands for the new fractal Sierpinski antenna. Such a behaviour is based on the self-similarity properties of the antenna's fractal shape, which might open an alternative way for designing new multiband and frequency independent antennas.Introduction: Most antenna designs are highly frequency dependent. The size of the antenna relative to the operating wavelength is the main bandwidth limiting factor. In the early 1960s, some selfscalable structures such as spirals, cones and log-periodic arrays were developed to design frequency independent antennas [2 ~ 51. The common factor is that the shape of all these structures remains invariable under some scaling transformations.

A small but long wire fractal antenna based on the Koch curve is presented. Experimental and numerical results show that the antenna improves the features of a common linear monopole. The radiation resistance is increased and the Q is reduced at each fractal iteration, approaching the fundamental limit on small antennas.Introduction: It has been shown that the self-similarity property of fractal shapes can be successfully applied to the design of multiband fractal antennas [1 ~ 41. It is the aim of this work to show how the space-fding properties [4] of many fractal forms can be used to design small antennas as well [4, 51. Experimental and numerical results are used to show how a fractal monopole can improve the radiaticln features of a common linear monopole (resonance frequency, radiation resistance, bandwidth), while some comments regarding the fundamental limit of small antennas are made.

Smart Cities need to be designed to allow the inclusion of all kinds of citizens. For instance, motor disabled people like wheelchair users may have problems to interact with the city. Internet of Things (IoT) technologies provide the tools to include all citizens in the Smart City context. For example, wheelchair users may not be able to reach items placed beyond their arm's length, limiting their independence in everyday activities like shopping, or visiting libraries. We have developed a system that enables wheelchair users to interact with items placed beyond their arm's length, with the help of Augmented Reality (AR) and Radio Frequency Identification (RFID) technologies. Our proposed system is an interactive AR application that runs on different interfaces, allowing the user to digitally interact with the physical items on the shelf, thanks to an updated inventory provided by an RFID system. The resulting experience is close to being able to browse a shelf, clicking on it and obtaining information about the items it contains, allowing wheelchair users to shop independently, and providing autonomy in their everyday activities. Fourteen wheelchair users with different degrees of impairment have participated in the study and development of the system.

The continuous development and improvement of low-power wireless communication technologies is enabling the emergence of many new applications in the field of the Internet of Things (IoT). One of the main areas of research within the Smart City context is smart health, which engages novel IoT initiatives to improve both quality and access to health care and smart services in general. In this paper we present CUIDATS, an IoT hybrid monitoring system for health care environments which integrates RFID and WSN technologies in a single platform providing location, status, and tracking of patients and assets. After its performance validation in a suitable testbed, CUIDATS has been deployed and evaluated with a high degree of success in a real hospital.