Optimizing Smart Helper Placement for Enhanced Cache Efficiency in F-RANs

TL;DR

This paper proposes an optimization method for smart helper placement in fog radio access networks to maximize cache hit rate, reduce content delivery latency, and improve network efficiency using RBFs and PSO algorithms.

Contribution

It introduces a novel placement optimization framework for smart helpers in F-RANs, combining user density modeling with particle swarm optimization.

Findings

Optimized SH placement increases cache hit rate.

Enhanced cache efficiency reduces content delivery delay.

Network fronthaul load is significantly decreased.

Abstract

Smart helpers (SHs) have been proposed to improve content delivery delays and alleviate high fronthaul loads in fog radio access networks (F-RANs). They offer an alternative to deploying additional enhanced remote radio heads (RRHs), which are often infeasible due to site constraints.} The optimal placement of SHs can significantly increase the number of users they serve which leads to enhanced cache efficiency and improved content delivery delay. In this letter, we optimize SH placement within an F-RAN to maximize the cache hit rate and further reduce the content delivery latency. We model the SH cache hit rate as a function of outage probability and user density distribution. We develop a function to estimate user density distribution leveraging the radial basis functions (RBFs) method and optimize SH placement utilizing the particle swarm optimization (PSO) algorithm. \an{Our} numerical results confirm the effectiveness of the proposed approach in maximizing the \an{SH cache hit rate}, thereby improving delivery delays and fronthaul loads of the network.