Optimal Allocation of Electromagnetic Spectrum to Support Tactical Wideband Communications

摘要

The Marine Corps is currently developing, purchasing, and fielding tactical wideband radios capable of connecting highly mobile units operating in rugged terrain over long distances. Wideband radios offer tremendous new capabilities, including high data rates and automatic traffic relay, but they have large electromagnetic spectrum requirements. We explore the challenges faced by a spectrum manager in allocating the minimum number of channels to support wideband communications for Marine Corps forces conducting tactical operations. A spectrum manager must consider not only the scarcity of available spectrum, but the technological limitations of the radios being supported. Specifically, the performance of a wideband radio depends greatly on transmission power, antenna gain, and other technical constraints, and on the amount of co-channel interference it receives from other radios operating on the same channel. We create a network communications model to capture the most relevant aspects of wideband communications, and use high-fidelity tools to simulate radio propagation in three realistic combat scenarios. We then formulate an interference-aware minimum-order channel assignment problem as a pure 0-1 integer program to determine the minimum number of channels required to support wideband communications. We examine an exact method of solving the problem, and develop and test a heuristic algorithm that in practice provides solutions at least as good as the exact method when processing time is not unlimited. We find that in the largest scenario, there is insufficient spectrum available to support the full wideband spectrum requirement, even with optimized channel reuse. To our knowledge, we are the first to describe an algorithm for solving an interference-aware minimum-order channel assignment problem for tactical wideband radio communications, and are the first to rigorously examine and quantify the ability to reuse wideband radio channels within the Marine Corps.