Millimeter wave is an essential and fundamental component for 5G mobile networks and AT&T’s plans. The 5G demo at TWS showcased the possibility and feasibility of millimeter wave radio access technology for the cellular networks of the future. Developed by Ericsson, the new systems incorporated key 5G technologies, including large system bandwidth, phased arrays with ultra-fast beam steering, feedback-based hybrid precoding, multi-user Multiple Input Multiple Output (MIMO), dynamic beam tracking and beam acquisition. The TWS debut marked the first time AT&T revealed this 5G technology to the public.
“What we’re showing here is a millimeter wave based system of what we envision 5G to be,” AT&T’s Assistant Vice President and WNCG Industrial Affiliate representative, Dave Wolter states. “It should be noted that 5G and millimeter wave are not synonymous and that 5G will operate in a different gigahertz as well as in millimeter wave. What we’re showing is the system operating on 800 megahertz of bandwidth. We’re demonstrating some of the enabling technology for millimeter wave.”
The technology for the demo included a base station and two antenna systems with an eight-by-eight array forming 41 beams. Both arrays, each with two polarizations, created four independent streams so the base station could talk to the user end equipment.
To demonstrate the new technology, AT&T provided a large screen TV that displayed a 4K video, the aggregated throughput of the system and slides containing basic concepts of the demonstration, including single user MIMO and elements that allowed the system to change uplink and downlink amounts to get different data rates.
The entire system was made of eight component carriers. While one carrier transmitted the video visible on the demonstration screen, the other seven ran data at the fastest possible rate. The 4K video displayed a view of the room in which the demonstration was held and the user equipment. White dots on the screen demonstrated where different beams could be focused by the base station and a green circle moved between different beams as it optimized throughput in the case of interferences and blockages. A small box in the corner of the screen demonstrated the probability of modulation and the coding scheme being used in real time.
“The demo allowed us to show some of the capability we have with millimeter wave,” Wolter states. “This is the first time AT&T has shared a demo of some of our work with the public. As we improve our capability we add to our testbed and feedback into 3GPP, where we use the benefit of our knowledge to help improve the standards.”
For more on the TWS 5G Demo, watch Dave Wolter’s presentation, courtesy of RCR Wireless, online at: https://youtu.be/drX6--JlkdE?list=PLwHfYh9uobIuP9Sk09g8f4DyZeZHYSXUd