Body area sensor network with automatically selected transmission gateways

Body area networks (BANs) are recently an innovative proposal for integrating data from wearable sensors in multimodal health and behavior surveillance systems. To allow unlimited subject's mobility, they commonly use wireless long-distance transmission (e.g. GPRS) requiring considerable amount of power, particularly in buildings, where the radio carrier is weak. We postulate to embed in the BAN an additional short-distance gateway (e.g. WiFi or Bluetooth) communicating with the corresponding access point being part of subject's house or workplace infrastructure, and providing a wired connection with the health center. This paper presents the project and test results of a simple prototype of human surveillance system with automatic switching between the short- and long-distance data gateway depending on the subject localization. Assuming the subject is spending up to 80% of the monitoring time within closed areas, the prototype allows to save a considerable amount of money for the communication service, and to raise the autonomy of the sensor network by 41%.