Evolution of Small Cell from 4G to 6G: Past, Present, and Future

TL;DR

This paper reviews the evolution of small cell technology from 4G to 6G, highlighting past deployments, current coexistence challenges with unlicensed spectrum, and future prospects involving 6 GHz band integration with Wi-Fi 6 and 5G NR.

Contribution

It provides a comprehensive overview of small cell evolution, discusses coexistence issues in unlicensed bands, and explores future integration of 6 GHz spectrum with 5G and Wi-Fi 6.

Findings

LAA deployments enable coexistence in 5 GHz band.

Future 6 GHz band will support coexistence of Wi-Fi 6 and 5G NR.

Small cell spectrum reuse is crucial for future high-capacity networks.

Abstract

To boost the capacity of the cellular system, the operators have started to reuse the same licensed spectrum by deploying 4G LTE small cells (Femto Cells) in the past. But in time, these small cell licensed spectrum is not sufficient to satisfy future applications like augmented reality (AR)and virtual reality (VR). Hence, cellular operators look for alternate unlicensed spectrum in Wi-Fi 5 GHz band, later 3GPP named as LTE Licensed Assisted Access (LAA). The recent and current rollout of LAA deployments (in developed nations like the US) provides an opportunity to understand coexistence profound ground truth. This paper discusses a high-level overview of my past, present, and future research works in the direction of small cell benefits. In the future, we shift the focus onto the latest unlicensed band: 6 GHz, where the latest Wi-Fi version, 802.11ax, will coexist with the latest cellular technology, 5G New Radio(NR) in unlicensed