In this paper, we investigate the design of high throughput relay-assisted millimeter-wave (mmWave) backhaul networks in urban areas. Different from most related works, we consider the deployment of dedicated simple mmWave relay devices to help enhance the line-of-sight (LoS) connectivity of the backhaul network in urban areas with abundant obstacles. Given a set of (logical) backhaul links between base stations in the network, we propose an algorithm to find high-throughput LoS paths with relays for all logical links by minimizing interference within and between paths. We also propose methods to modify the backhaul topology to increase the probability of finding high-throughput paths using our algorithm. Extensive simulations, based on a 3-D model of a section of downtown Atlanta, demonstrate that high-throughput topologies, with minimal inter-path and intra-path interference, are feasible in most cases. The analyses also yield some insights on the mmWave backhaul network design problem.
Optimal Path Construction with Decode and Forward Relays in mmWave Backhaul Networks
In this paper, we consider the problem of constructing paths using decode and forward (DF) relays for millimeter wave (mmWave) backhaul communications in urban environments. Due to the large number of obstacles in urban environments, line-of-sight (LoS) wireless links, which are necessary for backhaul communication, often do not exist between small-cell base stations. To address this, some earlier works proposed creating multi-hop paths that use mmWave relay nodes with LoS communication between every pair of consecutive nodes to form logical links between base stations. We present algorithms, based on a novel widest-path formulation of the problem, for selecting decode and forward relay node locations in such paths. Our main algorithm is the first polynomial-time algorithm that constructs a relay path with a throughput that is proven to be the maximum possible. We also present variations of this algorithm for constrained problems in which: 1) each possible relay location can host only one relay node, and 2) minimizing the number of hops in the relay path is also an objective. For all of the proposed algorithms, the achievable throughput and numbers of relays are evaluated through simulation based on a 3-D model of a section of downtown Atlanta. The results show more »
- Award ID(s):
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- Proceedings of the International Conference on Computing, Networking and Communications
- Page Range or eLocation-ID:
- 579 to 585
- Sponsoring Org:
- National Science Foundation
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