Millimeter wave veteran Cambridge gears for more competition after Spectrum Frontiers vote

Being early to any technology brings with it both risks and rewards, as Cambridge Broadband Networks (CBNL) can attest. The company, which was established back in 2000 by 10 engineers from Cambridge University, has honed its skills in the 28 and 39 GHz departments, both of which were part of last week's history-making Spectrum Frontiers ruling.

The FCC voted to create rules for a new Upper Microwave Flexible Use service in the 28 GHz (27.5-28.35 GHz), 37 GHz (37-38.6 GHz), and 39 GHz (38.6-40 GHz) bands, and an unlicensed band at 64-71 GHz. Prior to the start of the rulemaking, a lot of skeptics doubted the propagation characteristics of these bands could even make them practical for mobile operators.

CBNL has been working diligently over the years to engineer systems that not only work, but are economical. Since launching in the 28 GHz LMDS band in late 2014, CBNL's VectaStar point-to-multipoint (PMP) platform has been deployed in nine states, including California, Florida, Michigan, New York, Ohio, Rhode Island, Texas, Utah and Wisconsin. In April of this year, CBNL announced the launch of its 39 GHz VectaStar variant.

The FCC's move demonstrates growing validation of the strategy that CBNL has been pursuing for a long time. "For us, we think it's going to be the starting gun for something pretty spectacular," Mark Ashford, VP of North America at CBNL, told FierceWirelessTech.

CBNL figures it has about an 18-month to two-year head start over some others when it comes to supplying product for the 28 GHz band. Its unique advantage most likely comes in what Ashford calls the "productization" phase. "I'm sure there'll be other things out there. I think there's a lot of innovation in this space," including intelligent antenna array, he said. But, "when it gets down to it, it's the difference between field proven and something that's contingent on innovation which may or may not work."

In these higher spectrum bands in particular, which have been notoriously difficult to operate in, there's a lot of confidence put into field-proven solutions.

"I know when we first came to the U.S., there was skepticism given the issues with LMDS in the past," where expectations were extremely high for LMDS, but that market turned out to be poorly executed, Ashford said. There were other issues as well, but "we're cautiously optimistic," he said. "We welcome some more competition."

Ashford noted that the spectrum in these higher bands is more cost effective to acquire than traditional bands of 24 GHz or below, both per MHz and in absolute terms, and it's fairly widely available throughout the U.S. The 39 GHz band, for example, is available nationwide, including in each of the 175 economic areas. There's an average 800 MHz of 39 GHz available in the 30 largest U.S. cities – enough bandwidth to backhaul the busiest mobile base station or fixed wireless connection.

Last November, CBNL announced an agreement with StraightPath Communications to launch a combined 39 GHz product/spectrum solution. The agreement called for providing a seamless offering tied to StraightPath's nationwide 39 GHz spectrum assets, which cover each of the 175 licensed U.S. economic areas, with a new 39 GHz variant of CBNL's VectaStar licensed PMP platform.

StraightPath holds 828 spectrum licenses in the 39 GHz band, making it the largest single holder of 39 GHz licensed spectrum in the U.S. It also holds 16 LMDS A licenses and 117 B licenses in the 28 GHz band. Last year, the company said it hoped to eventually show how its prototype would demonstrate the viability of using 39 GHz for 5G services.

Related articles:
FCC OKs sweeping Spectrum Frontiers rules to open up nearly 11 GHz of spectrum
AT&T analysis highlights differences between 28 GHz, 37/39 GHz
Cambridge Broadband gets early start on 28, 39 GHz