Composite Interference Mapping Model to Determine Interference-Fault Free Schedule in WSN

The primary focus of most approaches that model interference in WSN is to understand the conditions under which the signals received by a destination node are interfered by the transmissions of other nodes. While these models support the basic understanding of interference phenomenon between two nodes; models that attempt to map the nodes whose transmissions can potentially interfere with other nodes is highly desirable. To this end, we propose the Composite Interference Mapping (CIM) model that provides a holistic framework for determining a comprehensive map of all potential interferers for each and every active link in the WSN. Based on CIM model, we propose three Interference-Fault Free Transmission (IFFT) scheduling algorithms viz., (i) IFFT-STDMA and IFFT-ESTDMA for topology-free, and (ii) LL-IFFT-ESTDMA for tree-structured WSNs, which also addresses the Exposed Station (ES) and Hidden Terminal (HT) problems. We present the analytical studies to support the CIM model developed in the paper. The results of the simulation experiments have shown that the proposed CIM-based IFFT algorithms perform much better compared to some of the well-known algorithms in performance metrics such as: number of time slots, packet drop, number of dead nodes, honouring precedence relations, and addressing ES and HT problems.