Adaptive Distributed Queuing Random Access Protocol for LoRa based IoT Networks

The Internet of Things is the idea of connecting any device to the Internet and to other connected devices. There are several wireless communication technologies in IoT depending upon the area in which they are employed. For device simplicity, Low Power Wide Area Network (LPWAN) tend to use a simple channel access control protocol such as Aloha, which impacts performance. While several LPWAN technologies are available in the field of IoT, focus on the Long Range (LoRa) network is still ongoing. Distributed Queuing LoRa (DQ-LoRa) algorithm has been used in the MAC layer of LoRa with fixed number of slots in its contention window for improving the performance of LoRaWAN. Depending upon the number of slots, either maximum throughput or minimum energy consumption could be achieved. The proposed work namely Adaptive DQ-LoRa (ADQ-LoRa) hovers over the dynamic slots mechanism for channel access control protocol in conjugation with the physical layer of LoRa. With every frame, the number of slots change depending upon the collisions and idle slots in the previous frame. With respect to DQ-LoRa protocol, which has the best performance, ADQ-LoRa gives 22% reduction in average delay and increases throughput by 12.5%. It has been shown to work better when nodes are more than 2000 in number, resulting in 4% decrease in energy consumption.