Interference Mitigation in IEEE 802.15.4-A Cluster Based Scheduling Approach

Tamilselvan Tamilselvan

doi:10.3844/jcssp.2011.80.89

Abstract

Problem statement: In universal networking environments; two or more heterogeneous communication systems coexisting in a single place. Especially, Wireless Local Area Networks (WLANs) based on IEEE 802.11b specifications and Wireless Personal Area Networks (WPANs) based on IEEE 802.15.4 specifications need to coexist in the same Industrial, Science and Medial (ISM) band. If the WPAN communication coverage is expanded using a cluster-tree network topology, then the 802.15.4 network is more susceptible to interference from neighboring WLANs. Approach: In this study, we propose an adaptive transmission power aware cluster scheduling algorithm using multiple channels in a WPAN in the presence of WLAN interference. Results: The algorithm includes node identification, channel allocation, clustering and time scheduling. To evaluate the performance of the proposed algorithm, the performance metrics such as Bit error, Packet Error Rate (PER), Throughput, Average End-End Delay and Average Jitter is measured through Qualnet simulation. PER is calculated from bit error rate. The simulation results are compared with the conventional TDMA scheme. Conclusion/Recommendations: The measurement result shows that the proposed algorithm is effective in an IEEE 802.15.4 cluster-tree network in the presence of multiple IEEE 802.11 interferers.

Highlights

As a low-power and low-cost technology, IEEE 802.15.4 is establishing its place on the market as an enabler for the emerging Wireless Sensor Networks (WSNs) (Petrova et al, 2006)
In this study we focus on the coexistence between these two major wireless standards that operate in the 2.4GHz Industrial Scientific Medical (ISM) band
Step 6: If the transmission power is not satisfying the Scheduling algorithm: In this study the two different above two cases the node is identified as devices namely IEEE 802.11b and IEEE 802.15.4 is invalid node and assigned sleeping time as total used with random topology

Summary

INTRODUCTION

As a low-power and low-cost technology, IEEE 802.15.4 is establishing its place on the market as an enabler for the emerging Wireless Sensor Networks (WSNs) (Petrova et al, 2006). Step 6: If the transmission power is not satisfying the Scheduling algorithm: In this study the two different above two cases the node is identified as devices namely IEEE 802.11b and IEEE 802.15.4 is invalid node and assigned sleeping time as total used with random topology. Assign the operating frequency as 2.413 GHz Step 4: Check for its CBR transmission Step 5: Assign the transmission time as 5 sec and sleeping time as 100 msec Step 5: If the transmission power is between 0 dbm and 3 dbm, the node = IEEE 802.15.4 (WPAN) node. If error presents get the transmission pair from each cluster and assign frequencies Step 9: Assign transmission time and sleeping time for new cluster members Step: If the transmission power is not satisfying the above two cases the node is identified as invalid node and assigned sleeping time as total simulation time. Nodeid_ch.frequency=Nodeid_ch.freq uency+5 } if (error_status==true) { for (i=1;i

RESULTS

Findings

DISCUSSION

CONCLUSION