Cost effective, scalable design of indoor distributed antenna systems based on particle swarm optimization and prufer strings

Global demographic trends place an increasing demand on the efficient and customizable design of large scale buildings and digital services offered within. Indoor wireless access has become standard and ensuring a thorough and economically sound wireless signal coverage throughout the building is not a trivial problem. An In-building Distributed Antenna System (IB-DAS) extends the wireless access from the base station to distributed antennas through a complex network of coaxial cables and power splitters. For high rise buildings and other multi-unit complexes, the initial cost of IB-DAS (cabling and splitters) and the running costs of powering the network are quite significant, hence the optimal design of an IB-DAS network is critical. Our proposition here is a novel In-Building DAS optimization model that utilizes Particle Swarm Optimization (PSO) to provide near optimal network topology that simultaneously minimizes the cost of the cabling and equipment for the whole building. Our PSO model uses Prufer number representation to efficiently traverse through different spanning tree solutions. As opposed to other approaches which solve this problem only partially (either equipment or cabling), typically considering a building as a single floor unit, our approach is a complete proposition for DAS optimization that is scalable and robust to deliver IB-DAS designs even for the tallest buildings beyond one hundred floors. We demonstrate that our model is capable of obtaining optimal solutions for small buildings and near optimal solutions for tall buildings.