Even if it is possible to say that each generation of mobile networks has used a new and specific set of spectrum resources, that pattern will be broken by 5G, if only because so many different bands will be used. What will be new are millimeter wave resources. But refarming and some new low-band spectrum also will be part of 5G.
In some markets, shared spectrum will be more important, and the sharing will take a number of forms, ranging from sharing of licensed and unlicensed spectrum to sharing between license holders and additional commercial customers.
Even if the 28-GHz spectrum will not be standardized by the International Telecommunications Union as among the globally-harmonized bands to be used for 5G (ITU IMT-2020), that band will be used in the United States for 5G.
In that regard, Verizon Communications is acquiring Straight Path Communications, a holder of 28-GHz and 39-GHz millimeter wave spectrum.
Verizon will purchase Straight Path for $3.1 billion in Verizon stock. The transaction is anticipated to close within nine months, subject to FCC review.
And though the idea is somewhat contentious, both the 28-GHz and 39-GHz regions are seen as underpinning early “pre-5G” deployments that explore new use cases for mobility networks, specifically, use in a fixed mode as a substitute for fiber-to-home access.
Traditionally, 28-GHz and 39-GHz capacity has been used for point-to-point connections. What is new is the effort to use both sets of frequencies in a non-line-of-sight manner, to support access operations, not signal trunking.
Ericsson research indicates that, when using 28-GHz radios in a fixed wireless mode, 78 percent of households can use indoor antennas (usually integrated into customer premises equipment. Wall-mounted antennas were needed for 17 percent or locations, while about five percent of locations required a rooftop-mounted antenna.
Those conclusions are based on tests of a suburban environment with 1,000 households per square kilometer. Twenty-five percent of the households use a 4K UHD video service (video on demand or linear) that requires a download speed of at least 15Mbps for uninterrupted playout of basic 4K video streams.
The transmission network used base stations on utility poles that are six meters tall. Terminal antennas are placed outdoors – often on rooftops or walls – as well as indoors.
The buildings are four meters to 10 meters tall, and there are trees in the area that reach heights of 5 meters to 15 meters and attenuate the signal.
The system design was based on a preliminary 5G New Radio (NR) concept operating at 28 GHz with a bandwidth of 200 MHz, utilizing beamforming and MU-MIMO and enabled by a base station antenna array of 8×12 cross-pole elements.
