Movement based time division multiplexing for near real time feedback body area network applications

A time division multiplexed coding system was designed and tested for a body-centric star network using a wireless node mounted in six different places in different time lots on the arm and leg and a central node (hub) on the chest during running. The proposed network allows a coordinated approach to gait analysis. The time sequence for communications between the wireless nodes and the hub is set during the first few steps as runners have different styles and can run at different speeds. After calibration the central unit sends a synchronization pulse during every running step and sets a unique transmission time window for each individual node. The time windows are scheduled when there is reliable communications between the hub and the sensor nodes around the body. Accelerometers on each node are used to identify these time windows for the diverse angles of rotation of the human limbs during running.