FWCC Webinar Recap: Potential problems permitting unlicensed RLAN operations in the 6 GHz band
  • February 4, 2020

FWCC Webinar Recap: Potential problems permitting unlicensed RLAN operations in the 6 GHz band

As many readers are aware, the FCC issued a notice of proposed rulemaking (NPRM) regarding RLAN operation within the 6 GHz bands. Over the last two and a half years, the FWCC has dedicated itself to protecting fixed links from t in these bands. Understandably so, this is especially important given the diversity of fixed link users in the 6 GHz bands; among others, utility companies, oil and gas companies, and local government agencies, including those dealing with public safety, have large numbers of 6 GHz links that perform unique and crucial tasks. There are approximately 97,000 fixed links in the 6 GHz bands.

Capacity Planning for Next Generation Utility Networks (Part 2)
  • September 19, 2017

Capacity Planning for Next Generation Utility Networks (Part 2)

Capacity planning guidelines for utility transport networks

In PART 1 of this blog, we provided an analysis of utility applications and expected capacity demands. Applications, especially security and surveillance, are rapidly increasing capacity requirements for utility networks. In this blog, we will outline an approach for performing capacity planning for a sample utility network in light of the applications traffic requirements.

FCC Rule Changes and the Future for Unlicensed 5.8Ghz PTP Backhaul Links
  • August 16, 2017

FCC Rule Changes and the Future for Unlicensed 5.8Ghz PTP Backhaul Links

The tragedy of the commons happens when people sharing a common resource are inclined to overuse it, degrading it so much that becomes useless. An example is a field open to all in which cattle, have grazed for generations. At some point, a cattleman increases the number of animals of his herd to maximize profit. 

  • May 22, 2015

Telecom Industry Participants call on FCC for E-band Action

While U.S. regulators decide on flat-panel antenna rules for E-band, operators and subscribers walk a tightrope of red tape.

While U.S. regulators decide on flat-panel antenna rules for E-band, operators and subscribers walk a tightrope of red tape.

Back in April the telecom experts over at CommLawBlog weighed in on a simmering issue in the 70-80GHz radio space. Since October 2012, the Federal Communications Commission (FCC) has mulled over a motion by the Fixed Wireless Communications Coalition (FWCC) to relax rules for flat panel antennas as well as a 2013 waiver to the existing rules while it considers a new rulemaking.

  • February 14, 2014

Could the Fixed Microwave Community Live without the L6GHz Band?

L6GHz-spectrum-could-be-allocated-away-from-fixed-microwave-service-at-the-2015-World-Radio-Conference-says-Aviat-Networks-February-14-2014

Photo credit: Broo_am (Andy B) / Foter / CC BY-ND

The fate of the L6GHz band for fixed microwave services could be decided when the World Radio Conference (WRC) meets in Geneva in 2015. Because these meetings at ITU headquarters only occur every three or four years, 2015 will be pivotal. Procedurally, at these conferences, delegates from member states review and—if necessary—revise the Radio Regulations, the international treaty governing the use of radio-frequency spectrum and geostationary- and non-geostationary-satellite orbits. They make revisions based on an agenda determined by the ITU Council, which takes into account recommendations made by previous world radiocommunication conferences.

Generally, the scope of world radiocommunication conference agendas is established four to six years in advance, with the final agenda set two years before the conference by the ITU Council, with concurrence of a majority of member states.

As WRC-15 approaches, many national regulatory authorities are busy harmonizing their national positions this year ahead of the actual conference in 2015. This conference is likely to see one of the biggest—if not the biggest—reallocations of spectrum ever undertaken. Much of this is currently being addressed under agenda item 1.1:

To consider additional spectrum allocations to the mobile service on a primary basis and identification of additional frequency bands for International Mobile Telecommunications (IMT) and related regulatory provisions, to facilitate the development of terrestrial mobile broadband applications, in accordance with Resolution 233 (WRC-12)

This will present the microwave community with a number of challenges and opportunities moving forward, one of which will be how we will address increased demand for capacity arising from mobile operators gaining huge swaths of additional access spectrum, enabling them to offer more and more high-demand, high-bandwidth services. This will require the regulatory environment governing fixed microwave to evolve at least in step or ideally ahead of this demand to ensure microwave remains an attractive and viable means for backhauling this access demand. The second challenge that the microwave community will face with WRC-15 agenda item 1.1 is more urgent: the proposal from Russia to open up the L6GHz band to mobile access.

The L6GHz fixed microwave band between 5925MHz and 6425MHz is available worldwide and with its propagation characteristics provides spectrum that is used for critical long-haul infrastructure links. The very nature of these links means that they are likely to be operational for many years and thus explains why many national regulators report stable and/or low growth in the number of licences issued in this band. In fact, with only a small number of channels available, in some locations congestion is becoming a problem. One scenario where use of this band cannot be replaced is when links have to cross open water, such as the Great Lakes in North America or the English Channel, the Oresund and the Aegean Sea in Europe. Here we see greatly increased activity from those building trans-national low latency networks linking together the various financial centers.

Now that we know the band’s use, why highlight it today?
Admittedly, while the Russian proposal under agenda item 1.1 is for shared access between microwave and mobile access, many industry insiders realize that the two services cannot realistically live side by side in the same geography. It’s not possible because mobile access requires nearly blanket area coverage to be viable. Add the fact that user terminals can be anywhere means sharing is difficult if not impossible to achieve. Some have proposed that mobile access at this frequency will only be attractive in urban areas, leaving rural areas to microwave. This is fine until you need to cross or terminate your L6GHz microwave link in an urban area. In reality, this approach is more of a migration solution than a sharing solution and is not in the best interests of the microwave community.

What to do?
The way WRC-15 works is that each member state has the same weighted vote as every other member. Consequently, any proposal for spectrum reallocation needs to be taken seriously. If there are concerns about a proposal then only by convincing a majority of national regulatory authorities of the validity of your argument can your position prevail. Aviat Networks has been working on several fronts in recent months to achieve a sufficiently large counter vote to the Russian proposals so that the status quo is maintained.

Lobbying national regulatory authorities
Specifically, Aviat Networks and other members of the U.S. microwave community have been working to formulate an American position. At present, this looks promising in terms of our L6GHz stance. Aviat Networks is also active in many African countries helping formulate national positions to oppose the Russians. The position of the African countries is key in this debate because there is not the fallback of long distance fiber. With the distances involved copper has never been a viable option for high capacity services. The current cloud over all this is Europe. Even with Europe’s very strong bent toward supporting growth of cellular services, many countries are still undecided, a situation further complicated by Russia’s CEPT membership. For example, Ofcom (U.K.) despite industry efforts is still unwilling to commit to a definitive strategy—or view—although the regulator admits a position must be agreed upon prior to the conference.

The message above is simple: if you use or want to use the L6GHz band for fixed microwave services find out what your national regulator’s position will be under WRC-15 agenda item 1.1. Remember, there are many bands up for discussion under this agenda item so ensure that you get your answer for the 5925-6425MHz band. Moreover, check whether it is a definitive position then lobby for the status quo to remain and oppose the Russian proposal.

Ian Marshall
Regulatory Manager
Aviat Networks

Related articles

  • December 19, 2013

E-band Wireless Comms: UK Announces New Approach

On Dec. 16 2013, Ofcom—the UK telecom regulator—announced a new approach for the use of E-band wireless communications in the United Kingdom. This new approach results from an earlier Ofcom consultation exercise in which Aviat Networks participated.

  • October 8, 2013

60GHz Band: a Solution for Small Cell Backhaul?

60GHz-microwave-backhaul-could-be-effective-solution-for-small-cell-if-regulators-in-various-nations-permit-its-use-says-Aviat-Networks-07Oct13

Small cell will enable mobile usage in dense urban environments but will need a backhaul solution to make it possible. Photo credit: Ed Yourdon / Foter / CC BY-SA

The Case for Small Cell Backhaul
As the search for frequency bands with suitable capacity for small-cell backhaul continues, frequency bands above 50GHz start to appear attractive because they offer both high-bandwidth availability and short range owing to their inherent propagation characteristics. The white paper available at the bottom of this blog examines spectrum in the 57-64GHz range to see whether it can be of use for small cell backhaul.

In many countries, the frequency range 57-66GHz is split into a number of discrete bands with differing requirements and conditions of use and/or licensing. These differences will be highlighted where applicable.

From a global point of view, the use of this spectrum by Fixed Services (FS) is being addressed by the ITU-R in its draft report on Fixed Service use trends in WP5C, which is currently under development and states:

57 GHz to 64 GHz
The radio-frequency channel and block arrangements of these bands for FS are defined in Recommendation ITU-R F.1497.
In 2011, around 700 links were in use in this band in a few administrations. The majority of the links are used for fixed and mobile infrastructure.
The air absorption around 60 GHz is over 10 dB/km. This condition restricts the hop length; on the other hand, the spectrum reuse efficiency is high. This feature makes the band suitable for small cell mobile backhaul.

Clearly, a global reported usage of 700 links would suggest a great deal of underutilization, although with unlicensed use in many countries it is difficult to know whether these figures are accurate or not. Regardless, there are reasons as to why this could be the case, while noting that the ITU-R believes this band has potential for small cell backhaul.

One factor is that this spectrum is not allocated solely to the Fixed Service. In fact, in many countries the Fixed Services have no access to this spectrum at all. A more detailed country-by-country breakdown follows. Please sign up below to receive the entire white paper.

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Ian Marshall
Regulatory Manager
Aviat Networks

  • September 20, 2013

Rules of the Game: Low Latency Microwave in a Multi-Regulatory Environment

[潛伏Latency] Charcoal, watercolor, fire on paper, 2011. Photo credit: RedPapaya (栩) / Foter / CC BY-NC-ND

[潛伏Latency] Charcoal, watercolor, fire on paper, 2011. Photo credit: RedPapaya (栩) / Foter / CC BY-NC-ND

Over the course of the last 18 months, a new application has grown by leaps and bounds for microwave networks: low latency. Low-latency microwave networks find most of their applicability in financial transactions, such as for executing trading instructions between major stock exchanges and trading houses in other cities.

Typically, low-latency microwave is used to “replace” traditional-fiber based networks linking financial centers. The business driver for microwave-instead-of-fiber in low latency is the time it takes to transmit trading instructions. With microwave, latency is reduced by a few milliseconds as compared to fiber. Nevertheless, those few milliseconds can translate into a trading edge over rival investors, which means big bucks. Low latency investors will pay a premium for this edge resulting in increased revenue for low-latency microwave network operators.

However, as with most financial functions, low latency is subject to a set of stringent regulations. The scenario is doubly difficult when low-latency microwave networks transmit across international boundaries. This compares to linking financial centers within a single country, which is relatively straightforward from a regulatory perspective because there is only one set of rules. The fact is when connecting financial centers in different nations and the operator’s network has to traverse other countries’ borders, the process becomes orders of magnitude more complex. Download the complete article for a fuller examination of some of these issues and why there should be widespread support for greater international harmonization of microwave regulation.

Ian Marshall
Regulatory Manager
Aviat Networks

  • August 23, 2013

Should National Telecom Regulators Impose Buildout Requirements on Operators?

FCC-Ofcom-and-other-national-wireless-regulators-should-have-spectrum-use-it-or-lose-it-policy-says-microwave-vendor-Aviat-Networks-August-23-2013

Photo credit: fingle / Foter / CC BY-NC-SA

In the mobile operator space in many countries, the national regulators are imposing so-called “buildout requirements” as a license condition on many wireless providers. In some countries, these requirements are restricted to licenses awarded by the auction process (e.g., cellular access spectrum) or block allocations while in others these conditions are attached to the majority of licenses.

Where buildout requirements are employed, a license typically has a clause that requires the licensee to build out a network/link or specified portion of a network within a certain period of time, with penalties imposed for failure to do so.

The rationale behind imposing these requirements is to ensure that after spectrum is assigned it is put to its intended use without delay. By doing this, or so the theory goes, bidders are discouraged from acquiring spectrum with the sole intent of blocking competitors’ activities without themselves offering service. Of course, the ultimate goal is the protection of spectrum—a finite and precious resource. There is no reason buildout requirements cannot be attached to any license grant, assuming that the detail of the requirements recognizes any constraints of the application for which the spectrum is sought.

Nevertheless, Aviat Networks is strongly against auctions and block allocations, but where these are a necessity then buildout requirements must be part of any award, with strong enforcement rules. The problem is that with strong enforcement operators and regulators can be at loggerheads and get tied up in court with lawsuits and countersuits for years. For example, in the U.S. you have the case of Fibertower. The FCC claims that Fibertower deliberately underbuilt its network and so moved to revoke its spectrum licenses. With the regulator moving against the operator, it came under insurmountable financial pressure and filed for bankruptcy. But even now, the operator’s creditors are fighting the FCC in order to recoup frequencies valued at more than US$100 million. So it is questionable whether this actually works in practice.

Microwave is the point
Focusing on point-to-point microwave, let’s examine the approach taken in two different countries. In the United States, for traditional link-by-link allocation, the FCC imposes an 18-month deadline by which time the link in question needs to be in service. However, in the United Kingdom, Ofcom imposes no such deadline. For certain applications, certain routes and sites are critical and can quickly become “full.” If these key locations are being filled by license applications that are not being translated into operational services, then this spectrum is effectively wasted as no one else can use it, nor is there any service being offered. Spectrum wasted in this manner reduces overall spectrum efficiency, and all spectrum authorities are motivated to ensure that spectrum is used in the most efficient way possible.

Of course having these rules is fine, but what happens when the rules are breached? In some cases, an operator will apply for an extension prior to the expiration of the original deadline; this may or may not be granted. However, the real test is what happens when the deadline passes. Ideally, what should happen is that the license(s) in question would be revoked and the associated spectrum made available for reallocation. Furthermore, if the spectrum in question was originally made available by block allocation or auction, then again, ideally, this spectrum should be returned to the pool of spectrum available for link-by-link licensing.

Additionally in shared bands, i.e., spectrum shared by the Fixed Service (FS) and the Fixed Satellite Service (FSS) should be governed by the same requirements in this instance. Therefore, unused/defunct FSS allocations/licenses should also be revoked with the spectrum being made available for reuse. In the case of FSS locations, this can have a significant effect owing to the geographic full-arc protection area that is usually associated with earth stations.

Counterpoint
The alternative viewpoint is that the current buildout requirements are counterproductive, in their aim to foster efficient use of spectrum. One reason cited for this view is that it takes time for an equipment supply ecosystem to develop, which will serve the spectrum users. However, when we examine this claim more carefully, it seems that this is often used where the spectrum has been awarded to a single user either by block allocation or by auction. We have written before about how auctions and block allocations are unsuitable for point-to-point microwave, and the claim above is a direct result of this process, which negatively impacts the number of operators. In turn, that reduces the ranks of equipment vendors, leading to thinner competition and, therefore, decreased incentive for innovation. This situation is made worse if the operator in question chooses a band plan that is nonstandard in terms of either existing U.S. or international arrangements.

Signal termination
In the final analysis, it does not serve any stakeholders’ goals to have valuable spectrum allocated but unutilized. Thus, having buildout requirements would appear to be a good idea. But along with that, an effective mechanism for reclaiming and making available to others spectrum that runs afoul of these rules is paramount to making the process work for the Greater Good. In Aviat’s view, buildout requirements are a valuable tool in ensuring spectrum efficiency and as such, their use should be seriously considered in all countries.

Ian Marshall
Regulatory Manager
Aviat Networks

  • June 17, 2013

5.8GHz FCC Rule Change: Good or Bad?

Microwave-radio-wireless-fixed-services-Backhaul-link-FCC-5GHz-rule-change-would-be-detrimental-comment-by-June-24-2013

Photo credit: John “I’m…kind of…fun” L / Foter.com / CC BY-NC

In the United States, the fixed service for wireless communications usually operates in bands licensed either on a link-by-link basis or by block allocation. So why is the 5.8GHz ISM band so important and why should the industry be concerned about current FCC proposals to change the rules of operation in this band.

Many operators use this band because they can install and operate a link in a very short period—much quicker than the usual route of prior coordination and license application that is required in other bands. There are numerous reasons why this approach is attractive, even if it is difficult to guarantee Quality of Service (QoS) in ISM. A common use of this approach sees the operator set up a link in the 5.8GHz band to get the link up and running while in parallel it goes through the coordination process for the same link in the L6GHz band. Then when that license is granted, the operator will move the link to the L6GHz band. This has the advantage that the same antenna may be reused and sometimes the same radio with just a filter change. Another use of the 5.8GHz band for fixed service links is in support of disaster relief efforts where because there is no need for prior coordination that means vital communications links can be up and running very quickly.

Under the current FCC Part 15 rules, equipment can be certified using section 15.247 whereby the above scenarios are attractive to operators as they mimic the conditions that can be found in the L6GHz band. However, the FCC has issued a notice of proposed rulemaking, NPRM, which will change this by requiring a reduction in conducted output power of 1dB for every dB of antenna gain over 23dBi for Part 15.247 point-to-point links. At present, the conducted power at the antenna port in this frequency range is limited to 1 watt, but there is no penalty applied to the conducted power in relation to higher gain antennas on point-to-point links. Should this proposal by finalized then this would reduce the effective range of point-to-point links in this band and would so change the dynamics that the ability to deploy a link in the 5.8GHz band and then “upgrade” to the L6GHz band at a later date would no longer be a feasible option. We would encourage all readers, especially those using the 5.8GHz band to file a comment with the FCC regarding Proceeding 13-49 that this particular change would be detrimental to many fixed link operators, as well as those who rely on this band for fast deployment during disaster recovery.

For more information on this proceeding, email Aole Wilkins at the Office of Engineering and Technology.

Ian Marshall
Regulatory Manager
Aviat Networks

  • April 26, 2013

The Gavel Comes Down: Auctions are Bad for Wireless Backhaul

Blue-payphone-unless-you-want-to-go-back-to-this-cellular-phones-need-cooperatively-licensed-microwave-backhaul-to-function-properly

Unless you want to return to payphones, cellular technology requires cooperatively licensed microwave backhaul to function properly. Photo credit: UggBoy / Foter.com / CC BY

Competitive licensing of fixed microwave backhaul bandwidth is a bad idea. And it should not go any further. The reasons why are laid bare in a new article in IEEE Spectrum by former electrical engineer and current telecom law firm partner Mitchell Lazarus. In general, he argues against federal spectrum auctions for microwave frequencies, and in particular for fixed microwave links. Undoubtedly, readers are familiar with the large cash bounties governments around the world have netted from competitive bidding on cellular bandwidth—first 3G and now 4G. An inference can be drawn from Lazarus’ article that some governments (i.e., the United States, the United Kingdom) had in mind a similar, if perhaps smaller, revenue enhancement through competitive auctions of microwave channels.

The problem lies in the fallacious thinking that operating fixed point-to-point wireless backhaul bandwidth is comparable to that of mobile spectrum. Whereas mobile spectrum license holders can expect to mostly—if not fully—use the frequencies for which they have paid top dollar, the same has not historically been true of license holders of microwave backhaul bandwidth. In most cases, mobile license holders have a virtual monopoly for their frequencies on a national, or at least regional, basis. Their base stations send and receive cellular phone signals omnidirectionally. They expect throughput from any and all places. So they have paid a premium to make sure no competitors are on their wavelengths causing interference.

On the other hand, U.S. holders of microwave backhaul licenses have specific destinations in mind for the operation of their point-to-point wireless networks. They only need to communicate between proverbial Points A and B. And, historically, they have only sought licenses to operate in their particular bandwidth on a particular route. They had no need to occupy all of their licensed frequency everywhere. That would be a waste. They just have to make sure they have a clear signal for the transmission paths they plan to use. To do that, before licensing, they would collaborate with other microwave users in the vicinity and a frequency-coordination firm to establish an interference-free path plan. Any conceivable network issues would usually be resolved at this stage prior to seeking a license from the Federal Communications Commission. Essentially, the FCC is just a glorified scorekeeper for fixed microwave services, passively maintaining its transmitter location license database.

But starting in 1998, with dollar signs in their eyes, governmental spectrum auctioneers started to sell off microwave frequencies in block licenses. The need for fixed microwave wireless services then was growing and has only grown fiercer with each additional iPhone and iPad that has been activated. However, access device throughput demand on one side of a base station does not necessarily fully translate all the way to the backhaul. Lazarus points out the example of now defunct FiberTower and its failure to make block microwave licenses work economically. After buying national block microwave backhaul licenses at 24 and 39 GHz, Lazarus notes, the firm resold the frequencies to Sprint and a county 911 emergency network operator. But those were the only customers. Lacking a robust enough utilization of its licensed backhaul frequencies, FiberTower had several hundred of its licenses revoked by the FCC and was forced into bankruptcy November 2012.

Subsequent auctions have attracted far fewer bidders and generated much less income for the Treasury Department. Much bandwidth has lain fallow as a result. And infrastructure buildout has stagnated.

Regulators should return the microwave backhaul licensing process to that of letting wireless transmission engineers cooperate informally among themselves, with the help of frequency-coordination firms, to arrive at fixed point-to-point wireless plans in the public interest. These are then submitted only for maintenance by the FCC or other regulators for traditionally nominal license fees—currently $470 per transmitter site for 10 years in the U.S., per Lazarus.

Forget the quixotic quest for chimerical hard currency. The commonweal demands it. You should demand it of the regulators—you can still give input regarding this scheme in some jurisdictions where it is under consideration. Clearly, the most efficient use of spectrum is to make it openly available to all because it means that every scrap of commercially useful spectrum is picked clean. We welcome your comments pro or con.

  • November 21, 2012

E-Band Global Regulation Roundup

Because of need for higher capacities, the trend toward shorter link distances for mobile backhaul and declining product costs, 70/80GHz (i.e., E-band) solutions are gathering significant interest for mobile backhaul and enterprise access applications. However, because these frequencies are new to most people, there is little understanding of costs and other issues related to licensing the 70-80GHz spectrum.

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