Smart Antenna Systems for Cooperative Low-Power Wireless Personal and Body Area Networks

Wireless sensor networks are attractive solutions that can be used in healthcare and sport performance monitoring applications which will enable constant monitoring of health data and constant access to the patient regardless of the current location or activity and with a fraction of cost of the regular face-to-face examination. Such a system is particularly useful in the case of in-home assistance of the elderly and rapid repatriation of recovering patents to their own homes, as well as for smart nursing homes, clinical trials and research augmentation. It was estimated in 2012, that wireless sensor solutions could save $25 billion worldwide in annual healthcare costs by reducing hospitalisations and extending independent living for the elderly. Current wireless sensor solutions are limited in that they do not provide the means to overcome obstacles and shadowing of propagating radio waves and also reduce the effect of interference in congested radio environments. The project will conduct research into new techniques and methods that combine both antenna and radio propagation engineering with networking and smart frequency agile communication systems. It aims to develop underpinning capabilities for an advanced low-power wearable antenna elements coupled with intelligent control algorithm capable of sensing and understanding the dynamic human body and dense indoor radio environment. Wireless monitoring of patients with critical illnesses can be taken as an example to demonstrate the benefit this technology will bring to the healthcare services. In dense hospital (or care homes) environments, there are many wireless standards present and radio communication is faced with many obstacles. In cases where there is no clear path between the patient's sensors (ECG, Blood pressure, blood sugar level, etc.) and the access points or the carer's receiving units, for example when a patient is laying face-down on a wireless sensor monitoring the heart, the communication link can be lost completely - a risk which is unacceptable to the healthcare profession. In cases when there is a lengthened radio propagation path from shadowing, the wireless sensor requires more power to communicate with the access point. For a system consisting of a number of independent sensors monitoring different vital signs, the power consumption can be significant enough to make the approach impractical, particularly for the elderly, whose reliability to recharge the power source cannot be guaranteed. Proposed in this project is a cooperative communication network of on-body wireless devices in which individual antennas in the network can adapt their radiation mode to switch between communicating with off-body units or using neighbouring devices on the same body. Appropriately configured, such a system will ensure that the data from the body-worn device can be communicated to the local base station or access point either directly or via one or more onbody sensor hops. So regardless of degree of shadowing - the system will autonomously find a communication pathway around the body to an antenna with the lowest path loss to the access point, hence minimising power consumption. The ability of the system to autonomously detect an uncongested part of the available radio spectrum for the communication link further adds to improved battery life.

The proposed project extends expertise in antennas and body-area networking to develop a novel approach to smart and cooperative wireless body-centric communications with low-power requirements, for example in: healthcare monitoring in-the-home; in dense environments such as hospitals; challenging and dynamic applications such as sport activity monitoring. The implications of the proposed technology will additionally have a tremendous impact on delivering user-centric information, treatments and life style advice. Beneficiaries are identified based on the expected period of impact. In the short term, the outcome from this project will primarily benefit two groups: (a) researchers interested in wearable wireless devices and antennas and propagation aspects of such devices and (b) intelligent control algorithm researchers working on smart communication networking and cognitive-based radio systems. In the medium term, the technologies developed in the project will benefit patients, healthcare practitioners, health services providers and the information technology community. For patients, low cost mobile patient monitoring has the potential for increasing the early detection of health problems not just for high-risk patients but lower-risk patients and eventually the general population. For healthcare practitioners, this allows the diagnosis and monitoring not to be limited to the brief time frames when the patient is in the hospital, and allow transient abnormalities to be captured at their naturally occuring states. For healthcare providers, the proposed research programme addresses the need for lowering healthcare costs, maximising efficiency and reducing hospital stay without compromising patient care. The UK general public, wider communities and government are identified as long term beneficiaries. Specifically, it will greatly assist the continuous monitoring of users for applications such as sport performance enhancement. Other area of interest is the well-being and safety of lone workers such as postmen and council workers. This project also benefits UK electronic industry for civil and military applications, in particular, system engineers for sensor specification, design engineers for antenna and sensor design and networking engineers for smart communications. Intellectual property rights will need to be protected to ensure relevance to those beneficiaries