More available frequencies will enable future wireless services. On balance, this is a good thing. As new frequencies bands are released or repurposed for commercial use, expect a proliferation of new and innovative wireless applications and use cases that enhance the user experience (UX).
The big implication here is that new use cases create demand for a lot of new wireless infrastructure.
Let’s be clear. One frequency neither fits all nor defines an application or use case. To wit, millimeter wave (mmW) is not 5G. Besides mmW, 3GPP standards-based 5G is being tested on other frequencies such as low-band 600 MHz and mid-band 3.4-3.7 GHz Citizens Broadband Radio Service (CBRS). Note that mmW at 60/80 GHz has been used for some time in high-capacity, short hops such as linking off-net buildings to fiber optic rings.
Radio frequency (RF) physics dictate that the higher the frequency, the shorter the wavelength thus shorter effective transmission distances and smaller coverage areas. Conversely, lower frequencies propagate over longer distances and cover wider areas. Available bandwidth or channel size at each frequency determines performance characteristics of data throughput, latency, and spectral efficiency.
This range of frequencies and performance allows operators to serve a multiplicity of uses. Different frequencies support different applications, some better than others.
Public mobile carriers acquired various frequencies for their wide-area cellular networks. 2G/3G used 800 MHz and 1.9 GHz along with 2.5 GHz WiMAX to achieve coverage. 4G LTE capacity enhancements came with 700 MHz and 1.7/2.1 GHz Advanced Wireless Services (AWS) spectrum. Availability of mmW at 28 and 39 GHz, low-band 600 MHz and mid-band 3.5 GHz CBRS are opening up a host of new 5G applications beyond mobile voice and data in both outdoor and indoor applications.
Fixed wireless access (FWA) enables internet connections in a variety of scenarios. Television White Spaces (TVWS) in the UHF (470-698 MHz) band, with its long range and non line-of-sight (NLOS) capabilities, performs better in some rural and remote situations than mid-band unlicensed 5.8 GHz that requires LOS transmission. 4G LTE in licensed 700 MHz is being used selectively in rural markets to deliver high-speed connections. Verizon’s 5G Home FWA uses 28 GHz mmW in a point-to-multipoint (PMP) configuration for high-speed broadband connections to urban and suburban customers where VZ does not offer its FiOS service.
Private industrial networks historically relied on unlicensed frequencies such as Mesh WiFi at 2.4/5 GHz, 900 MHz and 5.4-5.8 GHz for both PMP and point-to-point (PTP) applications. Private LTE deployments among utilities, oil & gas, mines and railroads at 2.5 GHz and 700 MHz provide enhanced data communications and information technology (IT)/operations technology (OT) integration. Additionally, utilities are using Upper 700 MHz A band with 1+1 MHz channels in narrowband IoT (NB-IoT) applications.
First responders’ mainstay has been narrowband VHF/UHF land mobile radio (LMR) for reliable public safety communications with FCC-designated 4.9 GHz in PTP links to connect radio sites. They now can take advantage of broadband LTE communications in 700 MHz Band 14 along with 700 MHz LMR.
In-building wireless (IBW) up to now has been dependent on carrier-fed public network frequencies for indoor coverage. Shared spectrum 3.5 GHz CBRS promises a myriad of new IBW applications without dependency on the carriers.
New use cases are being created across public and private networks by mixing-and-matching available low-, mid- and high band frequencies. In the end, expect greater demand for new infrastructure (read, radios and antennas) to deliver an enhanced UX.
John Celentano is an Inside Towers’ Contributing Analyst. Reach him at: firstname.lastname@example.org.
by John Celentano for Inside Towers
August 29, 2019