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Ultra wideband (UWB) technology has big potential for applications in wireless body area networks (WBANs). The inherent characteristics of UWB signals make them suitable for the wireless interface of medical sensors. In particular, implanted medical wireless sensors for monitoring physiological parameters, automatic drug provision, etc. can benefit greatly from this ultra low power (ULP) interface. As with any other wireless technology, accurate knowledge of the channel is necessary for the proper design of communication systems. Only a few models that describe the radio propagation inside the human body have been published. Moreover, there is no comprehensive UWB in-body propagation model that includes the frequency-dependent attenuation. Hence, this paper extends a statistical model for UWB propagation channels inside the human chest in the 1–6 GHz frequency range by including the frequency-dependent attenuation. This is done by modeling the spectrum shape of distorted pulses at different depths inside the human chest. The distortion of the pulse was obtained through numerical simulations using a voxel representation of the human body. We propose a mathematical expression for the spectrum shape of the distorted pulses that act as a window function to reproduce the effects of frequency-dependent attenuation.

The instrumentation for quantitative gait assessment must be small, lightweight and comfortable, in order to enable unconstrained mobility of tested subjects. In this paper, a design of a low-power multichannel wireless interface for kinetic gait measurement system is presented. Particular system feature is application of wireless telemetry. Power consumption of the battery powered wearable unit was reduced using a minimum number of low-power commercial components together with low-power design techniques. A new capacitive sensor interface circuit based on constant current pulse driving is shown. Power efficient optical wireless transmission employing digital pulse position modulation and � quasidiffuse� link is described.

In this paper we propose and analyze a new interface idling mechanism for improving energy efficiency of IEEE 802.11 based MAC hardware. A novel protocol state analysis technique is developed for detecting time windows during which a wireless interface consumes energy due to 802.11 overhearing. During this window, energy savings at the MAC layer is accomplished by forcing the wireless interface to a relatively lower-energy idling state. At the end of this window, the interface is transitioned back to its regular receiving mode. Energy savings are realized by exploiting the difference in power consumption between the overhearing state and the idling state. We evaluate the proposed protocol using ns-2 simulator. Simulation experiments validate that the proposed mechanism is capable of significantly reducing overhearing expenditure for newer 802.11 cards that support low-energy idling mode as described above. Our experimentation with Socket Communications Inc. low power 802.11 card demonstrate that the reduction in overhearing expenditure can be up to 23% and the subsequent network life extension can be up to 86% Results also show that the proposed MAC layer idling is fairly insensitive to network loading.

This paper describes a new Bluetooth/sup TM/-based wireless implementation of a mobile sensor. The solution reduces dramatically both power consumption and size of a wireless sensor improving earlier Bluetooth/sup TM/ implementations where multi-chip solutions were used and mobility was not supported. Three different implementations from multi-chip to single chip are described with the sensor wireless interface, the architecture, protocols and algorithms used. Achieved results are: (1) Implementation of 1 chip solution wireless sensor using the internal Bluetooth/sup TM/ module ADC for external sensing purposes. (2) Mobile sensor wireless monitoring with Bluetooth/sup TM/.

A p2mp PON architecture based analog mobile fronthaul approach that can accommodate 120 channels of 20MHz 64QAM LTE-A signals for Het-Net access has been experimentally demonstrated over sequential 20km fiber and wireless interface.

Describes a personal alert and a information access interface, which enables physicians in Coronary Care Units remote access to a data base which include monitoring information of any patient, and which covers the function of real-time alerting the physicians to important eventualities that are produced in relation to the different patients being monitored. This interface runs on a PDA in the form of a "palm-top PC", with Windows CE operating system.

In this paper we propose and analyze a new interface idling mechanism for improving carrier-sense energy expenditure of IEEE 802.11 based wireless network interfaces. A novel protocol state analysis technique is developed for detecting time windows during which a node consumes energy due to erroneous carrier sensing. During this window, energy savings at the MAC layer is accomplished by forcing a wireless interface to a relatively low-energy idling state. At the end of this window, an interface is transitioned back to its regular receiving mode. Energy savings are realized by exploiting the difference in power consumption between the erroneous carrier sensing state and the idling state. We evaluate the proposed protocols using ns-2 simulator. Simulation experiments demonstrate that the proposed mechanisms are capable of significantly reducing erroneous carrier sensing expenditure for newer generation of 802.11 cards that support low-energy idling modes as described above. Our experimentation with Socket Communication Inc.'s low power 802.11 card demonstrate that the reduction in combined overhearing and erroneous carrier sensing expenditure can be up to 62% and can extend network life by up to 154%. Results also show that the proposed MAC layer idling is fairly insensitive to mobility

Implanted biomedical devices have the potential to revolutionize medicine. Smart sensors, which are created by combining sensing materials with integrated circuitry, are being considered for several biomedical applications such as a glucose level monitor or a retina prosthesis. These devices require the capability to communicate with an external computer system (base station) via a wireless interface. The limited power and computational capabilities of smart sensor based biological implants present research challenges in several aspects of wireless networking due to the need for having a bio-compatible, fault-tolerant, energy-efficient, and scalable design. Further, em bedding thesesensors in humans add additional requirements. For example, the wireless networking solutions should be ultra-safe and reliable, work trouble-free in different geographical locations (although implants are typically not expected to move; they shouldn't restrict the movements of their human host), and require minimal maintenance. This necessitates application-specific solutions which are vastly different from traditional solutions.In this paper, we describe the potential of biomedical smart sensors. We then explain the challenges for wireless networking of human-embedded smart sensor arrays and our preliminary approach for wireless networking of a retina prosthesis. Our aim is to motivate vigorous research in this area by illustrating the need for more application-specific and novel approaches toward developing wireless networking solutions for human-implanted smart sensors.

This paper proposes an approach to save the energy consumed by a computer’s wireless network interface card (WNIC) due to the wireless communication activity in an IEEE 802.11 wireless local area network (WLAN). The energy efficiency design is considered at the MAC (Medium Access Control) layer, especially in its Distributed coordination Function (DCF), by reducing automatically the number of retransmissions due to collisions on the wireless channel.