Data Dissemination and Adaptive Backoff Algorithm for Wireless Cement Grouting Sensor Networks

System which can automatically accomplish cement-grouting and monitor real time based on JN5121 which is the first in a serial of low power, low cost IEEE802.15.4 /Zigbee protocol compliant wireless microcontrollers combining an on chip 32-bit RISC core is designed. CSMA/CA backoff algorithm specification in the IEEE 802.15.4 standard can not adapt to dynamic networks and multi-hop communication. This paper analyzes the model of data dissemination based on confidence coefficient and the adaptive backoff algorithm which can adapt to flow and avoid second collision ,then method of setting the backoff quanta equals to one or multiple of period of beacon cycle is proposed. Simulation results also show that model was effective in decreasing energy consumption of the node through reducing retransmission in multi-hop networks. In the end, part of program of wireless UART coordinator: based on JN5121 is given.