Energy Conserved Computation Offloading for O-RAN based IoT systems

Executing computation offloading under the mobile edge computing (MEC) network architecture is a widely recognized way to reduce latency and energy consumption for IoT systems. However, under legacy MEC network architecture, it is hard to jointly utilize global and local information to derive the optimal offloading strategy at the distributed edge servers, which may cause the latency and energy consumption reduction to the bottleneck. To meet the ultra-low latency and ultra-low energy consumption requirements of future IoT system, researchers start to focus on involving the recent emerging open radio access network (O-RAN) architecture into IoT systems. In this paper, we design a computation offloading strategy for an O-RAN based IoT systems to reduce the energy consumption of IoT devices (IoTDs) under the premise of latency requirement. Specifically, we first adopt O-RAN architecture to deploy the IoT system. Under the O-RAN based IoT system, we formulate computation offloading problem with the aim of minimizing energy consumption by jointly deciding offloading ratio, transmit power, and local processing speed. To make the optimization problem tractable, we decouple the original problem into two sub-problems, and the original problem is solved by iteratively solving these two sub-problems. Experimental results show that under our proposed O-RAN based IoT system, the strategy we obtained can reduce the average energy consumption of all IoTDs by more than 20%.