The shared Citizens Broadband Radio Service (CBRS) band remains in the spotlight this month, as Samsung today announced general availability of its CBRS Massive MIMO radio unit and other products.
With a unique three-tier sharing paradigm, the CBRS band has garnered interest from major mobile operators and smaller providers, as well as cable companies and enterprises, among others. The auction for 70 MHz of Priority Access Licenses (PALs) is underway at the FCC, with 271 qualified bidders. Deployments are already happening in the 3.5 GHz band as spectrum is commercially available for General Authorized Access (GAA) users. GAA users operate with third priority behind second-tier PALs and first priority federal incumbents.
Samsung initially launched CBRS-certified products late last year and now expanded availability to all mobile operators. Bringing broadband service to underserved areas through fixed wireless access over 3.5 GHz spectrum is one of the key use cases called out by Samsung’s Head of Customer Technology Solutions Sanjay Kodali in a blog post about the vendor’s CBRS gear.
“Samsung’s CBRS solutions in the mid-band 3.5 GHz spectrum are now providing operators with a fixed wireless access approach for rural areas to deliver service from a cell site to otherwise hard-to-reach homes and businesses,” Kodali wrote.
Roughly two years ago in September 2018, AT&T picked Samsung to supply its 5G-ready CBRS gear and discussed plans to use spectrum in the 3.5 GHz band to expand its fixed wireless access network. AT&T said it would use Samsung’s CBRS-compliant radios and base station equipment, and tap CommScope as the Spectrum Access System (SAS) provider.
In Kodali’s post, he emphasized that operators can add new radios to existing cellular sites to deliver wireless broadband more cost effectively than by using a cable or fiber approach. Kodali noted those options can pose a challenge in many underserved areas because of the cost and time associated with getting access to right-of-ways and needing to dig to lay down new cables or fiber.
Samsung’s first FCC-certified CBRS unit was delivered in July 2019 and the vendor said CBRS solutions are operating in multiple rural U.S. markets. In addition to the Massive MIMO unit, Samsung's CBRS solutions include strand, and pole or wall mount 2W small cells, and 20W Remote Radio Head.
The initial focus is on multi-carrier LTE, but Samsung’s CBRS equipment can be upgraded to 5G New Radio (NR). Beamforming massive MIMO antenna technology enables a single radio to provide broadband to several households and businesses, Kodali noted.
The CBRS gear leverages the maximum Instantaneous Bandwidth (IBW) and Occupied Bandwidth (OBW) specifications, which Kodali’s blog said reduces operators’ hardware investments for deploying CBRS networks by maximizing cell capacity and coverage. IBW is the spectrum bandwidth range a system can operate in and for OBW, a system can '"transmit" the specified bandwidht in MHz, Samsung Networks' Derek Johnston, head of marketing and 5G business development explained.
“Specifically, Samsung’s 64T64R CBRS Massive MIMO radio, now commercially available, can operate over the entire CBRS spectrum with an IBW of 150MHz,” wrote Kodali. “The massive MIMO unit can simultaneously transmit up to 100MHz of OBW, with a combination of 10 and 20MHz carriers (or spectrum bandwidth) across the entire CBRS Band.”
An operator isn't always able to place the spectrum bandwidth next to each other "so having a wide IBW gives them flexibility to place each carrier anywhere within the full CBRS spectrum band," Johnston said via email to Fierce, noting the vendor's MMU can transmit the maximum allocated bandwidth, which Samsung believes is "un-matched in terms of commercial solution availability."
Aside from fixed wireless, operators might also be looking at the 3.5 GHz band to fill in mobile coverage gaps or boost capacity, which Samsung said can be cost efficient with massive MIMO.
Samsung already has a foothold in next-gen networks in the U.S., supporting both AT&T and Verizon’s 5G rollouts. It has also deployed “tens of thousands of mid-band Massive MIMO radios” in South Korea, which Kodali suggested gives Samsung proven experience for commercial deployments looking ahead in the C-band.
“Samsung is already innovating in this area, including built-in flexibility to drive commercial mid-band solutions and develop new products supporting C-Band (3.7-3.98GHz),” Kodali wrote.
In second quarter earnings released Thursday, Samsung noted 5G investments both in South Korea and abroad were delayed due to COVID-19 pandemic. For the second half of 2020 outlook for Networks division Samsung said: "Despite uncertainties such as changes in 5G investment timelines by operators, continue to explore new opportunities to secure a foundation for growth."
The FCC’s much anticipated C-band auction is slated to kick off in December, offering 280 MHz of key mid-band spectrum for 5G. At this point, most 5G deployments in the U.S. have either used millimeter wave or low-band frequencies, and mid-band resources for 5G have been scarce. T-Mobile is the exception and actively working to turn on a deep pool of 2.5 GHz spectrum previously held by Sprint before the two carriers merged in April.
Notably, T-Mobile is the only nationwide carrier that hasn’t tapped Samsung for 5G equipment, at this point using Nokia and Ericsson as its main suppliers. Samsung was one of Sprint’s three 5G vendors for its initial (now deactivated) 5G network.