Scalable spectrum allocation for large networks based on sparse optimization

Abstract

Abstract-Joint allocation of spectrum and user association is considered for a large cellular network. The objective is to optimize a network utility function such as average delay given traffic statistics collected over a slow timescale. A key challenge is scalability: given n Access Points (APs), there are O(2 n ) ways in which the APs can share the spectrum. The number of variables is reduced from O(2 n ) to O(nk), where k is the number of users, by optimizing over local overlapping neighborhoods, defined by interference conditions, and by exploiting the existence of sparse solutions in which the spectrum is divided into k + 1 segments. We reformulate the problem by optimizing the assignment of subsets of active APs to those segments. An 0 constraint enforces a one-to-one mapping of subsets to spectrum, and an iterative (reweighted 1) algorithm is used to find an approximate solution. Numerical results for a network with 100 APs serving several hundred users show the proposed method achieves a substantial increase in total throughput relative to benchmark schemes.

Spectrum Sharing in Multi-Tenant 5G Cellular Networks: Modeling and Planning

“…In addition, the analytical model in [28] has assumed Poisson processes for the incoming and outgoing traffic for all tenants sharing the spectrum, which is not realistic as mentioned earlier. The optimisation of the spectrum allocation has been extensively studied in [14], [15], and [29]- [32]; however, the interaction between the spectrum utilization and the traffic characteristics for various tenants in multi-tenant cellular networks has not been considered yet. For this complex optimisation problem, a specific type of Learning Automata (LA) technique, referred to as pursuit learning [8], is shown to be effective in reducing the computational complexity of such complex optimisation problems [8], [33]- [35].…”

Joint Routing and Resource Allocation for Millimeter Wave Picocellular Backhaul

“…The core idea of considering all possible link activation patterns is inspired by the approach used in [9]- [12] for optimizing downlink spectrum allocation in cellular networks. Following [13], we reformulate the convex combinatorial resource allocation problem into a scalable mixed integer optimization problem. The problem considered here is fundamentally different from that of [9]- [13] due to the multihop nature of the network and the added problem of routing both uplink and downlink traffic.…”

“…Following [13], we reformulate the convex combinatorial resource allocation problem into a scalable mixed integer optimization problem. The problem considered here is fundamentally different from that of [9]- [13] due to the multihop nature of the network and the added problem of routing both uplink and downlink traffic.…”