Learning Based Routing Link Scheduling in Heterogeneous Wireless loT Networks

With the advent of 5G and beyond communication technologies, the consumer Internet of Things (loT) devices are evolving from the current-generation to the next-generation. Next-generation loT devices can support multiple communication interfaces and perform more functions. Accordingly, loT network technologies must adapt to the emerging next-generation loT devices. Routing is an inevitable technology in multi-hop loT networks. However, as loT devices become more and more diverse, loT networks become more complex. As a result, the routing problem becomes more and more complicated for traditional protocols and mathematical optimization approaches to provide optimal solutions. Machine learning based routing techniques have been recently proposed and can outperform traditional routing methods in complex network environments. To that end, this paper presents a machine learning based routing link scheduling scheme for heterogeneous wireless loT networks. We formulate the routing link scheduling problem as a combinatorial optimization problem, which is then parameterized for application of machine learning algorithm and the parameterized problem is solved using primal-dual approach with zero duality gap. A heterogeneous graph neural network (HetGNN) algorithm is proposed to update the primal-dual problems. We evaluate the proposed HetGNN model under networks with randomly deployed heterogeneous nodes. Compared with a convolutional neural network (CNN) model and a homogeneous GNN (HomGNN) model, the proposed HetGNN model can improve network throughput, reduce link capacity violation and interference link violation.