The use of CBRS spectrum in Verizon’s LTE network boosts average speeds by as much as 80% in the urban areas where the carrier has deployed those midband airwaves, according to new analysis from Opensignal.
Opensignal looked at average LTE download speeds for the three national operators in several cities with and without the use of midband spectrum. For AT&T, Opensignal looked at its LTE performance with and within use of 2.3 GHz; for Verizon, with and without 3.5 GHz; and for T-Mobile US, with and without its 2.5 GHz spectrum. The company analyzed only connections when the same amount of 40 MHz of bandwidth was used for the main and supporting spectrum bands.
The improvements that CBRS—which has much more stringent power restrictions on its operations than C-Band spectrum that operators spent billions on—illustrates why they were willing to spend so much on on C-Band, the benchmarking company points out.
Interestingly, not all midband spectrum is created equal when it comes to performance. Opensignal found that AT&T users connected with 2.3 GHz saw an increase of 8% in average LTE download speeds to 47.3 Mbps, while T-Mobile US users saw an LTE speed boost of 42.9% to 61.6 Mbps when the 2.5 GHz band came into play. But Verizon saw the biggest jump in speeds with CBRS: 4G download speeds on connections that included CBRS spectrum were 78.8% faster (74.4 Mbps) than Verizon 4G download speeds without CBRS involved.
On the downside, however, the lower power levels of CBRS have a strong impact on how quickly the signal strength deteriorates with distance from the cell site. Opensignal concluded in a blog post by Robert Wyrzykowski that the power level drop on the CBRS band is “significantly worse” than the impact of increased distance for users on 2.3 or 2.5 GHz spectrum.
Wyrzykowski wrote that in Opensignal’s analysis, users on CBRS spectrum close to a tower (less than 770 feet) averaged 136.7 Mbps in download speed, but that dropped by nearly half to 76.9 Mbps when users were between 770-1540 feet from the site, and then was reduced by about 80% when the user was approximately 2,300 feet away from the site. All spectrum bands saw a drop in speed as when the user was farther away from the site, the company noted, but the fall-off in CBRS performance was particularly steep.
That fall-off may not necessarily hold true in the same way for 5G in C-Band spectrum, Opensignal noted, because 5G New Radio is designed to improve the reach of midband spectrum compared to LTE.
Opensignal also reported that Verizon has increased its CBRS deployments in the past year. In October 2021, Opensignal users connected to CBRS spectrum in 36.3% of the metropolitan areas that the company analyzed, up from 24.8% in October 2020.
Read Opensignal’s full analysis here.