Big Questions Remain on Fixed Millimeter Wave for 5G
This was one of the crucial questions explored in a millimeter wave panel at Light Reading's Big Communications Event. Panelists -- and some industry heavy-hitters in the audience -- already understand that 28GHz and 39GHz can be used for megabit-speed, or even gigabit-rated, fixed wireless. Questions, however, are still bubbling about the range, propagation and installation of the next generation of fixed wireless.
The use of high-band millimeter waves in the US is not a new development. In fact, there are 14,000 wireless ISPs (WISPs) delivering fixed wireless over unlicensed and millimeter wave spectrum in the US, at download speeds that are anything between 1 Mbit/s and 200 Mbit/s.
The difference now is that mmWave use is being hung around the 5G standard with the promise of delivering a gigabit-speed fixed wireless alternative to cable. (See The Return of Fixed Wireless Access and 5G: The Fixed [Wireless] Is In!.)
Major players interested in this in the US include AT&T Inc. (NYSE: T) and Verizon Communications Inc. (NYSE: VZ) (See Verizon to Start Fixed 5G Customer Trials in April and AT&T: Prepping for the 5G World.)
As became clear at the panel, however, international players are also interested in mmWave. In particular, BT Group plc (NYSE: BT; London: BTA)'s Neil McRae, who was in the audience, said that the UK incumbent is examining the use of mmWave to connect some users.
On the panel, John Naylon, CTO of Cambridge Broadband Networks Ltd. , said that the vendor, which has more than 150,000 units deployed in over 50 countries, largely at 39GHz or 10.5GHz, is getting up to 200 Mbit/s at distances of up to three miles with professionally mounted rooftop radios that make line-of-sight connections. (See Fixed Wireless Revival: Windstream Eyes New Multi-Megabit Markets in US.)
And therein lies the rub: Operators hoping to use fixed 5G as a cable alternative want it to be cheaper than digging up roads for cable installations. Obviously, using a 5G radio to connect several houses helps to reduce costs. This will not be the case, however, if the operator has to make a truck roll -- or two! -- to get the user connected.
This was a topic of interest for the panel and audience. Would a subscriber with a window-mounted radio, and an antenna they have to adjust themselves, get a good signal?
In the audience, Kevin Linehan, VP of the office of the CTO at antenna provider CommScope Inc. , expressed confidence that it was a solvable problem. "Yeah certainly... Just think of what they do for DirecTV now. Users can choose professional installation or install the wireless TV receiver themselves.
"I don't know what regulations you have here," said BT's McRae, who threw in another requirement by noting -- at least in the UK -- that some of the environmentally friendly insulation available has dampened the radio penetration characteristics of mmWave radios.
How cheaply and efficiently fixed wireless 5G can be delivered is a crucial question if the concept is actually to be a success. More solid data will arrive this year as tests continue.
— Dan Jones, Mobile Editor, Light Reading