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

Abstract

To boost the cellular system's capacity, the operator's have started to reuse the same licensed spectrum by deploying 4G LTE small cells (i.e., 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 roll-out of LAA deployments (in developed nations like the US) provides an opportunity to understand coexistence's 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.

Device Discovery in D2D Communication: Scenarios and Challenges

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Distributed mechanism design for multi‐cell communications aided by multiple reconfigurable intelligent surfaces

“…In the example of Figure 2, BS 1 does not know the digital beamformer of BS 3 at first. Suppose that it has an initial estimate, V(0) 1 (3) . In each iteration t , the neighbours of BS 1, i.e.…”

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