HUMAN++: body area networks
It is anticipated that microsystem technology will increase the functionality of therapeutic and diagnostic devices to gradually match the needs of a society, which is ageing and spending more money on healthcare. It is expected that by the year 2010, technology will enable people to carry their personal body-area network (BAN) that provides medical, sports or entertainment functions for the user. This network comprises a series of miniature sensor/actuator nodes each of which has its own energy supply, consisting of storage and energy scavenging devices. Each node has enough intelligence to carry out its task. Each node is able to communicate with other sensor nodes or with a central node worn on the body. The central node communicates with the outside world using a standard telecommunication infrastructure such as a wireless local-area or cellular phone network. The network can deliver services to the person using the BAN. These services can include the management of chronic disease, medical diagnostic, home monitoring, biometrics, and sports and fitness tracking (figure 1).
Figure 1: The technology vision for the year 2010: people will be carrying their personal body-area network and be connected with service providers regarding medical, sports and entertainment functions.
IMEC is combining all its research and breakthroughs in integrated demonstrators. The most notable results in 2007 are highlighted below.
Wireless electrocardiography (ECG) patch
A wireless ECG patch for continuous heart monitoring takes away most discomfort caused by current cardiac monitoring appliances. The patch is wearable, free of wires, and easy to apply. It can be used to monitor a patient's heart under daily life conditions, away from the hospital. The patch core consists of a miniaturized wireless sensor node integrated on a flexible polyimide substrate. It integrates IMEC's single-channel ultra-low power biopotential application-specific integrated circuit (ASIC). The total size of the flexible core part is 60x20mm2. The electronics are integrated into textile to form the comfortable ECG patch (figure 2).
Figure 2: Wireless, flexible and stretchable ECG patch for comfortable heart monitoring.
Wireless EEG
Another notable wireless autonomous transducer solutions (WATS) integration is the 2-channel wireless electroencephalography (EEG) (brainwave monitoring) appliance powered by a thermoelectric generator. It harvests the heat radiated from the wearer's forehead. This wearable EEG monitor runs autonomous and maintenance-free, without the need to change batteries. The small size, low power consumption of only 0.8mW, and autonomy increase the patient's comfort and quality of life. Potential applications are recording brain activity, detecting imbalances between the two brain halves, or detecting brain traumata (figure 3).
Figure 3: Wireless EEG system powered by a thermoelectric generator.