Coexistence Between BLE and IEEE 802.15.4 Networks

Sammanfattning: As increasingly more IoT devices are being deployed simultaneously in the dense 2.4 GHz ISM band, interference could start occurring. BLE, and IEEE 802.15.4 are two protocols used in IoT devices, that both are now also capable of using IPv6 communication. Since the protocols coexist in this same frequency band, interference could become a problem. However, uncooperative coexistence between these two protocols under higher IPv6 data rates is understudied, and could be unfair. This thesis aims to study possible coexistence, and mitigate it using CCA.An experimental test setup consisting of two nodes for each protocol in close proximity was used to measure possible reliability issues and data rate decrease by logging sent connection based packets over serial, while limiting the amount of available overlapping data channels for each protocol.The results show that even though PDR is maintained, throughput can decrease. While still using all channels, BLE suffers a throughput decrease of 2.25% and IEEE 802.15.4 a decrease of only 0.34%. In the most extreme case BLE can suffer a decrease of 73.3% in throughput, while IEEE sees a mean throughput decrease of 10.9%. When enabling CCA in this extreme case, an improvement of 54.6% in throughput was observed for BLE, while IEEE 802.15.4 saw a relative loss of 3.5%. Therefore, the conclusion could be made that enabling CCA in IEEE 802.15.4 can enable more fair coexistence between the protocols.