A model for the service capacity at link layer, for a wireless, link-adaptive system is presented. The model includes imperfections in the adaptation chain (estimation error, estimation delay, acquisition error), and implementation implications (switching hysteresis). Transceiver characteristics and imperfections are independently represented by separate matrices. The dependence of effective capacityRc on the impairments is discussed using analytical, numerical, and simulations results. Examples show that the above effects should not be neglected in realistic performance analysis at upper layers.

This paper presents a model for the link service capacity that an imperfect adaptive radio link provides to upper layers. As the main contribution of this paper, the model includes a number of imperfections in the link adaptation chain, as well as implementation implications. The average goodput is expressed also in compact form and its dependence on the impairments is discussed using analytical, numerical, and simulations results. The model, to be used for analyses at upper layers, integrates physical channel, transceiver characteristics, and imperfections in a flexible way, by independent, separate matrices.

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Abstract-Provision of health care and well-being services at end-user residence, together with its benefits, brings important concerns to be dealt with. This article discusses selected issues in dependable pervasive eHealth services support.Dependable services need to be implemented in a resourceefficient and safe way due to constrained and concurrent, preexisting conditions and radio environment. Security is a must when dealing with personal information, even more critical when regarding health. Once these fundamental requirements are satisfied, and services designed in an effective manner, social significance can be achieved in various scenarios. After having discussed the above viewpoints, the article concludes with the future directions in eHealth IoT including scaling the system down to the nanoscale, to interact more intimately with biological organisms.

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Ultra-Wide Band (UWB) is a promising physical layer technology which potentially enables low power and high rate devices with applications for Wireless Personal Area Networks (WPANs) and for Wireless Body Area Networks (WBANs). The UWB technology considered in this paper, called MultiBand UWB, is based on Orthogonal Frequency Division Multiplexing (OFDM). Any physical layer technology requires a Medium Access Control (MAC) protocol to be coupled with. This paper focuses on a distributed Time Division Multiple Access (TDMA) MAC protocol to support high data rate applications, developed within the WiMedia Alliance [1].The aim of this paper is to study the dynamic beacon period extension and contraction when a newcomer device joins a existing beacon group (BG) and to evaluate the related energy consumption.