Wi-Fi Scaling and Performance in Dense Frequency Planned Networks

TL;DR

This paper investigates Wi-Fi network capacity scaling in dense, frequency-planned environments, revealing limitations imposed by MAC protocol and fading effects, and compares Wi-Fi performance to LTE in similar settings.

Contribution

It provides a detailed simulation-based analysis of Wi-Fi capacity limits in dense deployments and compares it with LTE, highlighting the impact of MAC and fading on throughput.

Findings

Wi-Fi throughput is limited by MAC and fading effects in dense networks.

LTE capacity grows faster than Wi-Fi as densification increases.

Simulations show Wi-Fi's virtual carrier sense partially mitigates interference.

Abstract

The capacity scaling of a Wi-Fi network with fixed transmit power is investigated. The 802.11 MAC appears to impose a hard limit on the area capacity by enforcing single transmissions in overlapped cell coverage areas. However due to the difficulty reading the packet header when transmissions either overlap or are faded, stations in different cells may lose synchronization with each other. A large frequency planned network with full propagation impairments of fast and slow fading is simulated in NS-3 with an upgraded receiver model supporting packet capture. Downlink Wi-Fi performance is compared to an equivalent LTE network on the same cell centers. Results show that Wi-Fi downlink throughput grows with densification limited by decreasing SINR and partially operational virtual carrier sense. LTE area capacity grows faster as it is only constrained by SINR.