CommLawBlog : Broadcast & Communications Lawyers & Attorneys : Fletcher Heald & Hildreth Law Firm : Telecommunications, FCC Regulation, Communications Act

Basically, the FCC expands on last summer’s rule changes by authorizing smaller antennas and wider channels. It also updates microwave efficiency standards to reflect the current predominance of IP networks.

Smaller antennas. The Order establishes a new antenna category, “Category B2,” which allows smaller antennas at 6, 18, and 23 GHz. (The former Category B, now dubbed “Category B1,” has a different, alternative set of parameters.) The FCC’s rules do not actually dictate antenna size, but set various other technical parameters, like beamwidth and radiation suppression, that directly affect antenna size. Smaller antennas pose a regulatory dilemma: on the one hand, operators like them because they are cheaper to manufacture, install, and maintain; plus, they generate fewer zoning and aesthetic objections. On the other hand, a smaller antenna cannot create as focused a beam as a larger one, resulting in greater potential interference with other antennas and potentially less efficient use of the spectrum. Also, on the receive side, smaller antennas are more sensitive to interference from sources away from the centerline of the antenna.

The FCC has historically struck a compromise: if a smaller antenna causes interference to another operator, it must upgrade to meet a higher set of standards that provide for a tighter beam (“Category A”). The new rules apply the same solution to Category B2. But the FCC does not impose a set time period for interfering antennas to upgrade, an omission that can lead to squabbles among operators. In a Second Further Notice of Proposed Rulemaking (SFNPRM) included as part of its decision, the FCC asks whether it would make sense to require interfering smaller antennas to upgrade just enough to resolve the interference, rather than having to meet full Category A standards. While perhaps a temporary benefit to the interfering operator, this proposal risks making Category A a nullity, and could create multiple rounds of heel-dragging and negotiation in getting an interfering antenna to upgrade.

Wider channels in the 6 and 11 GHz bands. The FCC will now allow Fixed Service operators to “stack” two adjacent channels to create a wider channel in the 6 and 11 GHz bands. One advantage of a wider channel over a channel pair is less hardware: an operator only has to generate one radio signal. It also offers more efficient use of the channel. A radio signal can’t occupy the entire channel width, and must leave a space between two channels. A “double-wide” channel eliminates this unused center band.

Updated efficiency standards.  Time was, all of the data transmitted on a radio link was “payload.” Communications were synchronized, so the receiver knew what to do with each bit coming from the transmitter. In a packet-switched world, however, each packet carries routing instructions and other network information in addition to its actual content. The link also transmits data used to establish and maintain the connection (such as forward error correction). Accordingly, the FCC has adopted a new definition of “payload capacity” as “the bit rate available for transmission of data over a radiocommunication system, excluding overhead data generated by the system” (emphasis added).

Similarly, the FCC has changed the existing minimum efficiency standards, which used to reflect the number of voice circuits a channel of given width must carry. The new rules incorporate efficiency standards based on bits per second per hertz. This approach is not only technology-neutral, but is scalable to any channel width.

Second Further Notice of Proposed Rulemaking. The SFNPRM seeks comment on (1) allowing smaller antennas in the 13 GHz band as well as at 6, 18, and 23 GHz; (2) clarifying the circumstances under which an 11 GHz licensee can reduce power instead of upgrading the antennas; and (3) allowing licensees to upgrade only to the extent needed to resolve interference, rather than being required to upgrade to full Category A standards as currently required.

Notice of Inquiry. In case these updates didn’t manage to completely catch the rules up to the technology, the Commission has indicated that it is prepared to step back and rethink its antenna regulations from the ground up.  A Notice of Inquiry invites a “broad discussion of our microwave antenna standards” – in part to accommodate non-traditional technology, such as non-parabolic antennas.

The new rules will take effect 30 days after publication in the Federal Register. Watch this space for updates.

• Allow fixed service wireless into the 7 and 13 GHz bands currently occupied by broadcast auxiliary services (BAS) and cable TV relay service (CARS). Broadcasters and cable operators use BAS and CARS to transmit video programming, both over fixed links (e.g., from TV studio to transmitter) and through TV pickup operations (those news vans with telescoping antennas on top). While sharing among fixed users is feasible, mobile and fixed operations don’t mix as well. News gathering vehicles must respond to breaking news quickly, without stopping to formally coordinate with other spectrum users, while fixed service systems need protection from interference to assure a high level of reliability.

The FCC divided the baby along demographic lines: it authorized fixed service operations in the BAS and CARS bands only in areas that have no TV pickup licenses. That’s half of the nation’s land mass, but only 10% of its people.  Allowing sharing in these areas may encourage rural buildout, as the FCC hopes, but will not go far to ease the congestion in urban areas caused by millions of data-hungry smartphones and tablets. The fixed wireless industry is therefore likely to continue exploring other workable spectrum arrangements, such as sharing with government spectrum at 7125-8500 MHz.

*** NOTE: If you’re a BAS or CARS licensee, make sure your information in ULS is correct, so that the Commission does not authorize an overlapping fixed service link. We have previously provided tips on how to do that here. The new rules also require registration of TV pickup receive stations. ***

• Permit adaptive modulation. The Part 101 rules governing fixed service operation require a minimum payload capacity (in megabits per second) for fixed links. Sometimes, though, passing atmospheric conditions interrupt a signal at this data rate, a condition called a “fade.” The connection is lost and the system has to be resynchronized, which can take several minutes. The Fixed Wireless Communications Coalition (FWCC) asked the FCC to allow “adaptive modulation”, a process which temporarily slows the data rate during a fade so as to keep the connection intact. The FCC agreed, but with a catch:  for efficiency, a fixed link using adaptive modulation must maintain the minimum payload capacity 99.95 percent of the time, or all but four hours of the year. This is a design requirement, not a performance requirement: links must be designed to comply, but the FCC will not require reporting of actual adaptive modulation use.

• Eliminate the “final link” rule.  Broadcasters have generally been permitted to use fixed Part 101 fixed service stations as part of the process of delivering programming to their transmitters – provided, that is, that fixed service stations not be used as the final RF link in that process. The Commission has now re-thought that rule, concluding that there may be significant benefits to be realized from eliminating it, with no associated costs. Result: the “final link” rule is now history.

The FCC rejected a proposal to allow fixed service licensees to deploy smaller “auxiliary” transmitters, all sharing the same spectrum as the primary station and all located within that primary station’s coordinated service contour. Proponents claimed that this would lead to more efficient use, or re-use, of the spectrum. Not so fast, said the Commission, which wasn’t convinced that primaries and auxiliaries could really co-exist without causing interference . . . or that the spectrum isn’t already extensively re-used, and re-useable, under existing rules. Plus, the “auxiliary” proposal would create a “perverse” – that’s the Commission’s word, not ours – incentive for applicants to propose excessive power for their primary stations, since the bigger the primary contour, the more auxiliaries could be crammed into it.  And anyway, a variety of other bands (think LMDS, 24 GHz and 39 GHz) already available could be used for the types of operations contemplated for “auxiliary” stations. Bottom line: a big negatory on the auxiliary proposal.

Finally, in the concurrent NPRM, the Commission has requested comment on:

• Allowing smaller Category B antennas in the 6, 18, and 23 GHz bands (three-foot, one-foot, and eight-inch antennas, respectively). Smaller antennas potentially cause more interference because they disperse energy more broadly, but are cheaper to manufacture, install, and maintain, and typically generate fewer zoning objections. There are no proposed changes to the more stringent Category A antennas, which are required wherever Category B antennas would cause interference.
• Exempting licensees from payload and loading requirements in non-congested (mostly rural) areas – specifically, in areas where Category B antennas are allowed. The goal is to lower costs and increase investment in rural broadband deployment. In congested areas, the Commission proposes exempting licensees that can make a special showing that: (a) the efficiency standard is preventing deployment; (b) there are no reasonable alternatives; and (c) relaxing the standard would result in tangible and specific public interest benefits.
• Allowing wider channels, or channel “stacking,” in the lower 6 and 11 GHz bands, as proposed by the FWCC. Where traffic demand is high, wider channels would result in lower costs, improved reliability, elimination of intermodulation issues, and increased spectrum utilization. The Commission seeks comment on allowing 60 MHz channels in the lower 6 GHz band and 80 MHz channels in the 11 GHz band.
• Revising waiver standards for microwave stations that point near the geostationary arc to conform to International Telecommunications Union (ITU) regulations.
• Defining the term “minimum payload capacity” as used in the efficiency standard rule. To accommodate application of the rule to Internet protocol radios, the Commission proposes rules, put forward by Comsearch, defining the term to include only capacity that is available to carry traffic, excluding overhead data used by the network itself, such as error correction and routing information.

The newly adopted rules will become effective 30 days after publication in the Federal Register. Check back here for updates on that front.  Comments on the issues teed up in the NPRM are due on October 4, 2011, and reply comments on October 25.

Wireless backhaul falls under the FCC’s Fixed Microwave Service (FS) rules in Part 101 of the rules. The Commission is examining a range of regulatory options to increase the “flexibility, capacity, and cost-effectiveness” of the microwave bands located below 13 GHz, while protecting incumbent licensees in these bands. 

Not all options, though. Some backhaul-related proposals – for example, proposals advanced by the Fixed Wireless Communications Coalition (FWCC) for combining adjacent channels and shared use of government spectrum – will be considered in separate rulemakings. But now on the table for consideration and comment are the following proposals advanced in the NPRM portion of the proceeding:

Allowing adaptive modulation. Part 101 spectrum is subject to certain minimum payload requirements (in terms of megabits per second per hertz). Those limits are intended to assure the efficient use of the frequencies. However, in some instances, ambient conditions create adverse effects such as atmospheric fading or “rain fade”, which cause an increase in bit errors and, on occasion, complete loss of communications. One technique for dealing with such conditions is to briefly reduce the data rate by temporary change in modulation type, a process called “adaptive modulation”. While adaptive modulation is already permitted by the rules, its use is subject to the minimum payload requirements. The problem is that, in order to maintain communications during some adverse propagation conditions, the payload capacity must sometimes be reduced below the required minimum.

In order to allow users to take advantage of adaptive modulation without unduly undercutting the goal of efficient use of the spectrum, the Commission proposes to maintain its minimum payload requirements “except during anomalous signal fading, when lower capacities may be utilized in order to maintain communications”.  Beyond that vague articulation, however, the NPRM lacks any detail. Instead, the FCC solicits suggestions for specifics (such as, e.g., how “anomalous signal fading” might be usefully defined, or how use of adaptive modulation should be (a) reflected in coordination notices and (b) recorded or logged).

Auxiliary FS stations. The NPRM seeks comment on allowing FS operators to deploy “auxiliary” stations. The concept of such “auxiliary” stations was first proposed to the FCC by Wireless Strategies, Inc. (WSI) in 2007. WSI envisages “simultaneously coordinate[d] multiple links whose transmitter elements collectively comply with the Commission’s antenna standards and frequency coordination procedures”. Essentially, the concept contemplates the re-use of a coordinated primary frequency by additional “auxiliary” links operating nearby on the same frequency. A number of opponents have questioned major elements of WSI’s thinking, arguing among other things that it would lead to excessive interference to other users, impair the integrity of existing systems, and generally be incompatible with traditional point-to-point FS operations.

While the Commission expresses interest in the notion of “auxiliary” stations, it offers no specific proposals. Instead, it poses a long laundry list of questions concerning regulatory limits that might be imposed on “auxiliary” stations.

Additional spectrum for FS.  The Commission proposes to allow FS operations in two additional bands (6875-7125 MHz and 12.7-13.2 GHz).  A variety of channel widths would be made available for FS operations, to provide opportunity for flexibility and increased use of digital technology. Those bands are currently allocated only to Broadcast Auxiliary Service (BAS) and Cable TV Relay Service (CARS). FS operations in the 6875-7125 MHz band would be subject to the same overall technical rules that currently apply to the adjacent Upper 6 GHz band, since common technical rules would allow use of similar equipment across the two contiguous bands. Technical specs for use of 12.7-13.2 GHz would not change, although the proposed rules would impose on that band the minimum payload capacity and loading requirements currently applicable to the 11 GHz band.

FS operations would be subject to existing frequency coordination procedures – that is, new FS users would have to coordinate with existing BAS and CARS users, whose existing licenses would not be modified as a result of the proposed rules.

With respect to coordination, though, the Commission asks whether the identification of BAS TV pickup stationary receive-only sites in the 6875-7125 MHz band should be made mandatory. Such identification is only optional at this point, and frequency coordination in that band is not as formalized.   The Commission recognizes that broadcasters use their BAS facilities for electronic news gathering (ENG) operations, and it specifically questions how use of the spectrum for FS might affect the flexibility of ENG. The Commission also asks whether FS use of the 12.7-13.2 GHz band would have any adverse effect on present or future use of that spectrum by cable operators.

Eliminating the “Final Link” rule.  The NPRM proposes to eliminate the “final link” rule which prohibits broadcasters from using licenses subject to Part 101 regulation as the final RF link in the distribution chain of broadcast programming. The Commission expects that this will encourage fuller use of Part 101 spectrum.

In addition to the relatively specific points addressed in the NPRM portion of the Commission’s action, a number of more general questions are presented for comment in the NOI portion. They include:

Lower efficiency standards in rural areas.  Would lowering efficiency standards (minimum payload capacities) in rural areas lower backhaul costs while maintaining spectrum efficiency? And in connection with this query, the Commission questions how
“rural” should be defined.

Smaller antennas.  Should Part 101 be revised to permit smaller antennas – the idea being that such antennas would likely also be cheaper, more flexible, more easily deployed, etc.?  Anyone who thinks the answer to that question is “yes” is invited to provide detailed information about the particular FS bands that might be affected, new standards that might be applied, the geographical areas in which the new standards could or should be applied, and so forth. 

Other modifications.  What other modifications to the Part 101 rules – or any other policies or regulations, for that matter – might be made to promote flexible, efficient and cost-effective provisions of wireless backhaul service?

Comments are due October 25, 2010. Reply comments are due November 22, 2010.