Joint Flow Routing and DoF Allocation in Multihop MIMO Networks

Recently, degree-of-freedom (DoF)-based models have been widely used to study MIMO network performance. Existing DoF-based models differ in their interference cancellation (IC) behavior and many of them suffer from either loss of solution space or possible infeasible solutions. To overcome these limitations, a new DoF-based model, which employs an IC scheme based on node-ordering was proposed. In this paper, we apply this new DoF IC model to study a throughput maximization problem in a multihop MIMO network. The problem formulation involves joint consideration of flow routing and DoF allocation and falls in the form of a mixed-integer linear program (MILP). Our main contribution is an efficient polynomial time algorithm that offers a competitive solution to the MILP through a series of linear programs (LPs). The algorithm employs a sequential fixing framework to obtain an initial feasible solution and then improves the solution by exploiting: 1) the impact of node ordering on DoF consumption for IC at a node and 2) route diversity in the network. Simulation results show that the solutions obtained by our proposed algorithm are competitive and feasible.

最近，基于自由度（DOF）的模型已被广泛用于研究MIMO网络性能。现有的基于DOF的模型在其干扰取消（IC）行为方面有所不同，其中许多模型均遭受解决方案空间的损失或可能不可行的解决方案。为了克服这些局限性，提出了一种基于DOF的新模型，该模型采用了基于节点顺序的IC方案。在本文中，我们将这种新的DOF IC模型应用于多ihop Mimo网络中的吞吐量最大化问题。问题制定涉及对流程路由和DOF分配的联合考虑，并以混合企业线性程序（MILP）的形式落下。我们的主要贡献是一种有效的多项式时间算法，该算法通过一系列线性程序（LPS）为MILP提供了竞争解决方案。该算法采用一个顺序固定框架来获得初始可行解决方案，然后通过利用来改进解决方案：1）节点排序对iC的DOF消耗的影响，以及2）网络中的路线多样性。仿真结果表明，我们提出的算法获得的解决方案具有竞争力和可行性。