U.S. spectrumWhen Michael Marcus and others at the FCC created the "unlicensed bands," they had little idea about how it would go. Wi-Fi has been a major game changer but that wasn't clear at the beginning. It's yet one more example of what creativity makes possible. Today, we see some congestion in the "commons," as well as proposals to squat on a large share. We need some "rules of the road" to manage the congestion fairly and efficiently. But they need careful design to have minimal impact on innovation. 

Fred Goldstein reminds me that the band is used for more than Wi-Fi.

As we develop rules, we have to consider these interests as well. 

There are other users of the unlicensed bands, though, of which WISPs are the most visible, though public safety and private systems are also quite common.  These are basically unlicensed microwave, not WiFi, even if they are based on WiFi chipsets using variant protocols.  These are used in both point-to-point and point-to-multipoint modes. Your typical WISP has a PtP backhaul radio feeding PtMP access points that are shared among 10-40 subscribers, who can be up to 10 miles away. WiFi arbitration doesn't work over such distances. Vendors thus create proprietary arbitration schemes, like Ubiquiti's airMax and MikroTik's Nstreme.  Some also use GPS synchronization so that multiple radios on a site (e.g., sectors and backhauls) transmit and receive at the same time, to avoid mutual interference, and to control end to end latency.
These systems use directional antennas, often with high forward gain, at both ends, which both maximizes range and minimizes interactions in other directions.  So they rarely conflict with actual WiFi systems. LAA, like Cable WiFi, would just add to the background din that potentially impairs their performance. 
Many problems to solve and we need the best ideas.

dave askOn Oct 1, Verizon turned on the first $20B 5G mmWave network. It will soon offer a gigabit or close to 30M homes. Thousands of sites are live in Korea; AT&T is going live with mobile, even lacking phones. The hype is unreal. Time for reporting closer to the truth.

The estimates you hear about 5G costs are wildly exaggerated. Verizon is building the most advanced wireless network while reducing capex. Deutsche Telekom and Orange/France Telecom also confirm they won't raise capex.

Massive MIMO in either 4G or "5G" can increase capacity 4X to 7X, including putting 2.3 GHz to 4.2 GHz to use. Carrier Aggregation, 256 QAM, and other tools double and triple that. Verizon sees cost/bit dropping 40% per year.

Cisco & others see traffic growth slowing to 30%/year or less.  I infer overcapacity almost everywhere.  

Believe it or not, 80% of 5G (mid-band) for several years will be slower than good 4G, which is more developed.


5G Why Verizon thinks differently and what to do about it is a new report I wrote for STL Partners and their clients.

STL Partners, a British consulting outfit I respect, commissioned me to ask why. That report is now out. If you're a client, download it here. If not, and corporate priced research is interesting to you, ask me to introduce you to one of the principals.

It was fascinating work because the answers aren't obvious. Lowell McAdam's company is spending $20B to cover 30M+ homes in the first stage. The progress in low & mid-band, both "4G" and "5G," has been remarkable. In most territories, millimeter wave will not be necessary to meet expected demand.

McAdam sees a little further. mmWave has 3-4X the capacity of low and mid-band. He sees an enormous marketing advantage: unlimited services, even less congestion, reputation as the best network. Verizon testing found mmWave rate/reach was twice what had been estimated. All prior cost estimates need revision.

My take: even if mmWave doesn't fit in your current budget, telcos should expand trials and training to be ready as things change. The new cost estimates may be low enough to change your mind.