Abstract—SimpliciTI^TM is a low power radio frequency protocol from Texas Instruments (TI), which supports peer to peer and star topologies. The system uses Access point (AP) as data hubs, and end devices (ED) to realize the sensor functionality. APs need to be always ON to ensure they can respond to join requests from new EDs and collect data from existing EDs in the network. This is not practical with long-running battery operated APs. We can reduce the energy requirements in the network by putting APs to sleep, but this requires careful synchronization so that the APs will be ready to receive data when the EDs transmit. We implement a time synchronization algorithm to ensure that APs are awake whenever an ED sends data. We also propose a simpliciTI based tree topology where one ED (named PCED, personal computer end device) is made common to the network of multiple APs and now PCED acts as the data hub. To manage the data traffic at the PCED we implement time division multiplexing along with store and forward function on EDs and APs.

Index Terms—Star and tree topology, time division multiplexing in wireless sensor networks, time synchronization in SimplicTI, wireless sensor networks.

The authors are with the Department of Electrical Engineering at Indian Institute of Technology Madras, Chennai, India (e-mail: vaibhavpratapsingh07@gmail.com).

Cite:Vaibhav Pratap Singh, Nitin Chandrachoodan, and Anil Prabhakar, "A Time Synchronized Wireless Sensor Tree Network using SimpliciTI," International Journal of Computer and Communication Engineering vol. 2, no. 5, pp. 571-575, 2013.