U.S. operator Sprint, a Softbank company, and Samsung Electronics announced that on the streets of the city of Suwon in South Korea they recently tested massive MIMO on 2.5 GHz spectrum in a real-world environment to support Sprint’s efforts to increase LTE Plus wireless capacity and coverage and offer gigabit service to its customers.
During the field testing in Suwon, massive MIMO Samsung radios, equipped with vertical and horizontal beamforming technology, achieved peak speeds of 330 Mbit/s per channel using a 20 MHz channel of 2.5 GHz spectrum. The companies stated that capacity per channel increased approximately four-fold, cell edge performance increased three times and the overall coverage area expanded compared with current radios.
Sprint has deployed 8T8R (8 transmit, 8 receive) radios across its U.S. network, and the test with Samsung was designed to compare the performance of massive MIMO radios with 8T8R radios. The test cases and requirements were jointly developed by Sprint and Samsung and included a variety of performance scenarios involving multi-user and non-stationary testing.
For the tests, Samsung provided the massive MIMO network infrastructure as well as test network design, operation, data collection and processing. Both companies plan to use the results of the testing to prepare for the commercial deployment of massive MIMO in the U.S. and in other markets globally.
Samsung noted that massive MIMO radios involve the use of more antenna elements, for example, 64T64R uses 128 antenna elements, whereas 2T2R/4T4R/8T8R configurations are used in a typical 4G LTE network. The massive MIMO antennas also use advanced horizontal and vertical beamforming technology to focus and transmit cellular signals into targeted locations. This enables more efficient use of spectrum to deliver faster speeds and higher data capacity in high-traffic locations.
Sprint plans to deploy massive MIMO radios with 128 antenna elements (64T64R) using its 2.5 GHz spectrum in cities across the U.S. to increase capacity by up to eight-fold. In March, Sprint became the first U.S. carrier to introduce gigabit-class LTE on a live commercial network with a launch in New Orleans.
In New Orleans, Sprint implemented three-channel carrier aggregation and 60 MHz of 2.5 GHz spectrum, combined with 4 x 4 MIMO and 256QAM higher order modulation to achieve Category 16 LTE download data speeds over a TDD network. With massive MIMO radios using 64T64R, Sprint expects to be able to deliver capacity beyond 1 Gbit/s and reach between 3 and 6 Gbit/s bandwidth per sector.
