Body Sensor Networks Reliability Enhancement Algorithms in Sport and Biomedical Applications

摘要: Wireless Networking is the fastest growing segment of networking industry. In medical and sport industries, Body Sensor Networks (BSNs) are used to monitor human body. BSNs have numerous design challenges, including network topology, reliable data delivery in a timely manner, minimal power consumption. Other performance parameters, such as throughput coverage, equally important. The object this project was achieve an efficient optimal BSN that acquire movement physiological data, using sensors at various places on body sending receiving unit (gateway) located chest for re-transmission information remote computer (locally or cloud) further processing presentation. This important athletes, coaches viewing public, it provides real-time monitoring rapid improvement player during training rehabilitation sessions. An investigation into best node locations made maximum connectivity chest, angular window nodes transmit typical movements, running walking. Preliminary results showed that, while distance between transmitting changes significantly, presence scattering from limbs causes most significant effect received signal strength. These measurements demonstrated strength greater than -70dBm (the radio communications threshold) can vary 20% 74% recorded time different locations. The use accelerometer sensor each allows these positions be identified burst transmission occur reliably. modules were determine link by recording traffic lost runners transmitter (foot, leg arm), identify windows diverse angles rotation running. wrist gives connectivity. approximate swing calculation algorithm employed find losses. Different rates tested against loss 98% 62% reliability 250kbps 2Mbps respectively. With central novel energy-efficient multiplexing method on-body wireless communication implemented based rhythmic style individual self-calibrate scheme so transmissions only when high predicted. technique takes advantage periodic actions implement dynamic division multiple access (TDMA) strategy five-node with very little overhead, long sleep times transceivers robustness errors. all successful, except two attempted medium simultaneously. aggregated 90% achieved, compared 63% employing traditional algorithms. also trade-off channel occupancy generated provide network. advanced gesture adopted collect acceleration predict limb position athlete moving. reduced overall increased reliability. As result, losses 30% 1%, continuous communications. Experimental reported five subjects moving formations grassed field smart Carrier Sensing Multiple Access (CSMA) technique. forces repeatedly sense carrier frequency recognize other out coverage. test reports sink A placed head normally distributed coverage approximately 5 meters least 80%. 100% successful within programmed not neighbours list existence modified accordingly stage test. availability proximity playing their respect spent one field.