Evolution of Small Cell from 4G to 6G: Past, Present, and Future
This paper is an incremental review for researchers and operators interested in the evolution and coexistence challenges of small cell technologies in shared spectrums.
This paper reviews the evolution of small cell technology from 4G to 6G, highlighting the shift from licensed spectrum to unlicensed bands like Wi-Fi 5 GHz (LTE LAA) and future 6 GHz bands. It discusses the challenges and opportunities for coexistence between cellular technologies (4G LTE, 5G NR) and Wi-Fi standards (802.11ax) in these shared spectrums.
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