Distributed MIMO, Li-Fi Offer Promise for In-Building Networks: IEEE Expert

multiple-input and multiple-output (MIMO) and light fidelity (Li-Fi). The IoT will mostly use in-building networks, he said. There will likely be a “gap” between how 5G turns out and expectations, and “in-building networks can help close that gap,” he said. Wi-Fi connections can be as fast as 10 Gbps with Wi-Fi 6, but access points “are shared among multiple users,” he said: “There can be interference from other access points if it’s not very well coordinated. … All these wireless problems are typically managed through the listen-before-talk protocols and that is not very efficient.” With 5G “the issue is the limited coverage,” he said. 802.11, part of the IEEE 802 set of local area network technical standards, offers a network with “low complexity and low costs” and “increasingly introduces similar features” as those offered on carrier networks, Jungnickel said. Some wireless LANs are being built using a technology known as distributed MIMO, he said. “This architecture is known for provision of seamless mobility; it can do advanced interference control,” he said. “It can provide very reliable links because of the redundancy. It can transmit from multiple sites. The latency is low.” The technology is “really promising,” he said. Jungnickel also sees promise in new Li-Fi networks, which transmit data via LED or infrared light. Unlike Wi-Fi, which uses RF, Li-Fi technology needs only a light source with a chip to transmit an internet signal via light waves. “It provides much higher area capacity in small hot spots,” 100 Mbps per square meter “and easily more,” he said: “Light is quite a clean channel, so you can … guarantee the delivery of data at very low latency. It’s robust against jamming because it doesn’t interfere with radio, and it also provides enhanced privacy.”