Coexistence Aware Clear Channel Assessment - From Theory to Practice on an FPGA SDR Platform

Wireless sensor networks are used by an ever growing number of applications which have ever increasing Quality of Service requirements. The available unlicensed industrial scientific and medical bands – where wireless sensor networks typically operate – are crowded with a number of technologies interfering with each other. Delivering a sufficiently high QoS within these frequency bands is therefore becoming more and more difficult. A theoretic concept named Coexistence Aware Clear Channel Assessment (CACCA) promises more reliable QoS when different technologies utilize the same. Within this paper we propose two methods to perform CACCA and create an SDR prototype to show that CACCA can achieve a high packet error rate reduction in an IEEE 802.15.4 network when it coexists with IEEE 802.11.