IBM and Ericsson have created a compact silicon-based millimeterWave (mmWave) phased array integrated circuit operating at 28 GHz that has been demonstrated in a phased array antenna module designed for use in future 5G base stations. This research breakthrough could accelerate the launch of 5G communications networks and support new mobile enterprise and user experiences enabled by very high data rates, including IoT, connected vehicles, and immersive virtual reality.
2017 has been described as a defining year for 5G. More countries and governments are opening up new frequency portions of the electromagnetic spectrum, including portions known as millimeter wave bands, which are more than 10 times higher than the frequencies currently used for current mobile devices, offering a new source of bandwidth for cellular networks that are being made available for 5G networks.
Scientists at IBM Research and Ericsson reached their breakthrough as a result of a two-year collaboration that set out to develop phased array antenna designs for 5G. IBM's expertise in highly integrated phased array mmWave IC and antenna-in-package solutions, together with Ericsson's expertise in circuit and system design for mobile communications, helped the team reach several new technological milestones.
The first release of the 3GPP 5G specification is targeted to be ready by 2017/2018, but there has already been much progress in the industry with field tests and demonstrations of new user experiences and capabilities made possible by the higher bandwidth, lower latency, greater density and lower energy requirements of 5G networks.
5G is expected to support data rates exceeding 10 Gbps in certain scenarios. New capabilities are designed to allow users to download a full-length HD movie in seconds, provide very high bandwidth and uninterrupted live streaming experiences in highly dense environments such as sports or concert venues, experience 'life-like' response times to enable remote surgery or fully immersive virtual reality experiences, as well as see battery life of 10 years for remote cellular devices that may be part of IoT environments.
For future 5G phased array deployments to be commercially viable the size, weight, cost and performance of the component are important factors. The IBM and Ericsson team's result, the world's first reported silicon-based mmWave phased array antenna module operating at 28 GHz, is a significant step towards meeting this challenge. The module, which consists of four monolithic integrated circuits and 64 dual-polarized antennas, measures approximately 2.8" by 2.8", or about half the size of a typical smartphone. Achieving this compact form factor is necessary to support the vision of this technology's widespread deployment, especially in indoor spaces and dense downtown areas.
Another performance advance reported by the team is the demonstration of concurrent dual-polarization operation in transmit and receive modes. This capability enables one phased array antenna module to form two beams simultaneously, doubling the number of users to be served at the same time and so improving the overall value and economics of the technology.
A major hurdle for the use of mmWave signals in mobile communications is achieving sufficient range between radios to support target applications. At 28 GHz, each antenna is tiny and individually would support short communication distances, but combining multiple such tiny antennas not only increases the range but also enables steering of signals in specific directions. The IBM and Ericsson team's phased array design supports beam-steering resolution of less than 1.4 degrees for high precision pointing of the beam towards users.
A paper describing the IBM Research and Ericsson team's work, "A 28 GHz 32-Element Phased-Array Transceiver IC with Concurrent Dual Polarized Beams and 1.4 Degree Beam-Steering Resolution for 5G Communications," was presented on February 7 at the 2017 International Solid State Circuits Conference in San Francisco.
