Reliable and energy-efficient communications for wireless biomedical implant systems

Reliable and Efficient Data Communication Protocol for WBAN-Based Healthcare Systems

Wireless Body Area Networks (WBANs) become very attractive in the research community area and are getting growing interest because of their suitability for medical applications. They are designed such, they can be located on, in or around the patient body and are used to monitor medical signs and forward them to medical servers. Proficient energy and Quality of Service (QoS) are the main requirements for a dependable design in a such networks. In this article, the authors propose a reliable and power efficient routing approach for healthcare systems with the aim to balance the trade-off between the QoS requirements and the energy consumption. Their approach operates in an efficient computation way, where the sink device manages the routing paths avoiding the sensors to be involved in computation and consequently on the energy consumption. They conducted intensive simulations and the obtained results show that Their approach offers effective results in terms of transmission load, response time and energy consumption.

Mutual-Information-Based Incremental Relaying Communications for Wireless Biomedical Implant Systems

Network lifetime maximization of wireless biomedical implant systems is one of the major research challenges of wireless body area networks (WBANs). In this paper, a mutual information (MI)-based incremental relaying communication protocol is presented where several on-body relay nodes and one coordinator are attached to the clothes of a patient. Firstly, a comprehensive analysis of a system model is investigated in terms of channel path loss, energy consumption, and the outage probability from the network perspective. Secondly, only when the MI value becomes smaller than the predetermined threshold is data transmission allowed. The communication path selection can be either from the implanted sensor to the on-body relay then forwards to the coordinator or from the implanted sensor to the coordinator directly, depending on the communication distance. Moreover, mathematical models of quality of service (QoS) metrics are derived along with the related subjective functions. The results show that the MI-based incremental relaying technique achieves better performance in comparison to our previous proposed protocol techniques regarding several selected performance metrics. The outcome of this paper can be applied to intra-body continuous physiological signal monitoring, artificial biofeedback-oriented WBANs, and telemedicine system design.

Network Coded Cooperative Communication in a Real-Time Wireless Hospital Sensor Network

The paper presents a network coded cooperative communication (NC-CC) enabled wireless hospital sensor network architecture for monitoring health as well as postural activities of a patient. A wearable device, referred as a smartband is interfaced with pulse rate, body temperature sensors and an accelerometer along with wireless protocol services, such as Bluetooth and Radio-Frequency transceiver and Wi-Fi. The energy efficiency of wearable device is improved by embedding a linear acceleration based transmission duty cycling algorithm (NC-DRDC). The real-time demonstration is carried-out in a hospital environment to evaluate the performance characteristics, such as power spectral density, energy consumption, signal to noise ratio, packet delivery ratio and transmission offset. The resource sharing and energy efficiency features of network coding technique are improved by proposing an algorithm referred as network coding based dynamic retransmit/rebroadcast decision control (LA-TDC). From the experimental results, it is observed that the proposed LA-TDC algorithm reduces network traffic and end-to-end delay by an average of 27.8% and 21.6%, respectively than traditional network coded wireless transmission. The wireless architecture is deployed in a hospital environment and results are then successfully validated.

Characterization and analysis of dynamic implant communication channels based on inhomogeneous model

Implant communication plays an important role in achieving information exchange among implantable devices in personal health care. In this paper, the characteristics of dynamic implant communication channels (ICCs) are studied by using a set of 30 inhomogeneous human body models (frames) which corresponded to one period of a walking motion. The gain variations of three different ICCs (from belly to head, right wrist, and right ankle) are investigated at 21MHz, 403.5MHz, and 2.45GHz, respectively. The results show that the ICC gain may be affected by body posture, body shadowing effect, multipath fading, and earth ground. In addition, compared with the ICC gain at 403.5MHz and 2.45GHz, the ICC gain at 21MHz is motion-insensitive in implant communication.

Cooperative wireless network control based health and activity monitoring system

A real-time cooperative communication based wireless network is presented for monitoring health and activity of an end-user in their environment. The cooperative communication offers better energy consumption and also an opportunity to aware the current location of a user non-intrusively. The link between mobile sensor node and relay node is dynamically established by using Received Signal Strength Indicator (RSSI) and Link Quality Indicator (LQI) based on adaptive relay selection scheme. The study proposes a Linear Acceleration based Transmission Power Decision Control (LA-TPDC) algorithm to further enhance the energy efficiency of cooperative communication. Further, the occurrences of false alarms are carefully prevented by introducing three stages of sequential warning system. The real-time experiments are carried-out by using the nodes, namely mobile sensor node, relay nodes and a destination node which are indigenously developed by using a CC430 microcontroller integrated with an in-built transceiver at 868 MHz. The wireless node performance characteristics, such as energy consumption, Signal-Noise ratio (SNR), Bit Error Rate (BER), Packet Delivery Ratio (PDR) and transmission offset are evaluated for all the participated nodes. The experimental results observed that the proposed linear acceleration based transmission power decision control algorithm almost doubles the battery life time than energy efficient conventional cooperative communication.