February 21, 2018
Analysts with Signals Research Group (SRG) who studied Verizon’s 28 GHz system in Houston say they came away with a great appreciation of the promises of millimeter wave spectrum. It’s not a panacea for all the world’s fixed and mobile broadband needs, but they walked away pretty stoked about the prospects for 5G millimeter wave systems.
The analysts just released an executive summary of a new report that chronicles their study in Houston, accompanied by a video of their escapades. The tests were done the last week of January and used a drive test scanner from Rhode & Schwarz to collect performance metrics.
They found that millimeter wave signals are far more resilient than expected, even at distances exceeding several thousand feet. Tree foliage, passing school buses, buildings, glass and parked cars impacted the received signal, but the resultant signals were still capable of delivering meaningful data rates. However, they say that promising Gigabit data speeds to all homes may prove to be challenging, especially in the near term.
The study comes as Verizon prepares to commercially launch a 5G-based fixed wireless service this year. SRG tested two Verizon 5G Technical Forum (5GTF) cell sites with each cell site supporting two sectors. These 5G cell sites were located about 1,400 feet from each other and were macro sites, which the analysts found a bit surprising since small cells are typically associated with 5G millimeter wave deployments.
Samsung is the infrastructure supplier for Verizon in the Houston market and the analysts said they believe the trial network in Houston is now supporting commercial traffic. They also said they believe it’s the industry’s first independent network benchmark study of a 5G commercial test network.
Based on numerous walk tests and stationary tests involving line-of-sight, non-line-of-sight and near-line-of-sight conditions, they found that millimeter wave signals are far more resilient than expected, even at distances of more than several thousand feet. “Who would have thought a millimeter wave signal in an area 100% blocked from the serving cell tower by the surroundings would still be capable of supporting good data speeds?,” the report states.
There is one thing they do not buy, however. Verizon management is on record for promising Gigabit speeds to its serviced customers, but “we don’t share this view with near-term deployments unless Verizon aggressively deploys 5GTF small cells (i.e., brings the consumer and the 5G access point closer together), and/or mounts CPEs in ideal exterior locations, and/or limits its customers to only those customers that it knows live in a location with suitable radio conditions that can support Gigabit speeds,” the analysts said.
“If the goal is to deliver downlink/uplink broadband speeds that exceed what most US consumers can get today from their fixed line service provider, then it is a slam dunk—especially when limited to regions that Verizon is likely targeting with its forthcoming offering,” SRG said. “However, if consumer expectations are for reliable Gigabit-per-second speeds then someone(s) is going to walk away disappointed.”
Verizon’s Chief Engineer and Head of Wireless Networks Nicola Palmer said last year that she and her team were finding that millimeter wave propagates a little better than they thought it would in terms of line of sight and elevation. Their tests showed they were able to get up as high as the 19th floors of a building and they were also seeing speeds in and above the 1 gigabit-per-second range beyond 2,000 feet. Those type of findings were based on Verizon’s trials with non-paying customers in 11 markets at the time.
SRG also noted that while Verizon is currently using the 5GTF specification, they believe the data they collected and the results concluded from their analysis are equally applicable to the industry-defined 3GPP 5G NR specifications.