Intermediate measurement node for extension of WSN coverage
Rabin Bilas Pant, Hans-Petter Halvorsen, Frode Skulbru, Saba Mylvaganam · Journal of Cyber Security and Mobility · 2013
Wireless Sensor Networks (WSN) are considered as viable options for data communication for various monitoring and control applications in industries. Improvements in transmission range, security issues, real time monitoring and control issues, system integration and coexistence with other WSN systems are some of the main issues limiting their widespread usage in the industries. After a brief literature survey on some of the recent WSN applications and security management, two designs of WSNs based on Wi-Fi and Zig-bee are presented in this paper. Wireless Distribution System (WDS) and router mode are used in Wi-Fi based and Zig-bee based designs respectively. Zig-bee based design was economic but supports lower sampling rate. Wi-Fi based design was expensive but supports high sampling rate up to 51.2 K samples per second per channel. WSN was setup using NI Zig-bee modules. NI WSN-3202 (sensor node) and NI WSN-9791 (Gateway) were connected in star network topology and multi-hop network topology. Using multi-hop topology, indoor transmission range was increased significantly from 23.1 meters to 47.1 meters with link quality more than 55%. Since maximum sampling rate of Zig-bee modules is1 sample per second per channel, monitoring measurands demanding high sampling rates are deliberately avoided in this work. In both topologies, temperature is the only measuarand handled by both WSN solutions in the solutions presented here.