Before the
FEDERAL COMMUNICATIONS COMMISSION
Washington, D.C. 20554
In the Matter of )
)
Amendment of the Commission's Rules to ) ET Docket No. 96-102
Provide for Unlicensed NII/SUPERNet )
Operations in the 5 GHz Frequency )
Range )
To: The Commission
COMMENTS OF THE AMERICAN RADIO RELAY LEAGUE, INCORPORATED
IN RESPONSE TO NOTICE OF PROPOSED RULE MAKING
The American Radio Relay League, Incorporated (the League),
the national association of amateur radio operators in the United
States, by counsel and pursuant to Section 1.415 of the
Commission's Rules [47 C.F.R. 1.415], hereby respectfully
submits its comments in response to the Notice of Proposed Rule
Making (the Notice), FCC 96-193, released May 6, 1996. The Notice
proposes to amend Part 15 of the Commission's rules to permit use
of 350 MHz of spectrum at 5.15-5.35 GHz and 5.725-5.875 GHz by a
new category of unlicensed equipment, called NII/SUPERNet
devices. These would provide short-range, high-speed wireless
digital communications on an unlicensed basis. The Commission's
goal in the Notice proposal is to create new wireless local area
networks (LANs) in furtherance of the so-called "National
Information Infrastructure" (NII), a group of interlinked
networks of all types of communications facilities to serve the
people of the United States in the future. With respect to the
frequency bands proposed and the compatibility of the instant
proposal with continued operation by incumbent users, including
the Amateur Service, the League states as follows:
I. Introduction
1. The Commission's Notice in this proceeding is based on
two petitions for rule making, RM-8648 and RM-8653. The latter,
filed by Apple Computer, Inc., proposed the use of the 5.725-
5.875 GHz band for so-called "NII" operation. What the Apple
petition entailed, far different from the short-range, high-speed
digital communications proposed by the WINForum petition, was a
community network with path lengths up to 15 km, power levels for
non-spread-spectrum devices at up to one watt, and unlimited
antenna gain (and apparently unlimited antenna beamwidth). The
WINForum and Apple concepts were radically different in scope and
concept. The League objected, in comments filed July 10, 1995, to
the expansion of the Part 15 regulatory concept for unlicensed
devices, proposed by Apple, especially in an amateur allocation.
The League did not object to the WINForum proposal for use of the
lower portion of the 5 GHz band. Most importantly, and as noted
by the Commission in the instant Notice, the Apple proposal
sought a change in the table of allocations, which is not
possible for Part 15 devices. (See, the Notice, at Footnote 34).
Rather, those devices are merely permitted to operate in bands
allocated to other services on a non-interference basis.
2. The Apple petition, when filed, was woefully incomplete
in terms of technical specifications and sharing studies relative
to incumbent users. As the League noted in its July 10, 1995
comments:
The Apple petition is amorphous, in that it does not
propose any specific rules changes (other than
amendment of the Table of Frequency Allocations, 47
C.F.R. 2.106, to make spectrum available for the
proposed new service). It contains no technical showing
to support the proposed allocation whatsoever; and
there is no showing of compatibility between the so-
called "NII" (National Information Infrastructure) band
allocation proposed by Apple, and existing Government
and non-government users (including Part 15, Part 18
and Part 97 users). The petition is rife with glowing
predictions of universal access by the public for
whatever communications purposes are desired, but it
contains no real information about the possibility of
coordination of use between and among unlicensed users
in the bands, or coordination between and among inter-
service users. It contains only the vaguest references
to compatibility with existing services in the 5150-
5300 and 5725-5875 MHz bands. One can only conclude
from the absence of any proposed operational rules and
the lack of any technical compatibility showing that
there is in fact no possibility of coordination, and
that the opportunities for compatible sharing are
little more than hopeful, but baseless, predictions.
Neither does the petition contain an adequate
discussion of alternatives to the specific allocations
proposed in the petition; Apple indicates that the
proposed 5 GHz allocations would be used both for long
and short distance communications, but does not
establish that frequencies above 40 GHz would not be
sufficient (or indeed preferable to the 5 GHz bands
proposed) for short-range paths.
II. The Notice Proposal Should Limit NII/SUPERNet Devices
To the 5.15-5.35 GHz Band
3. The Commission has solved some, but not all, of these
problems by virtue of the proposed technical rules contained in
the Notice, including the proposed power limitation of -10dBW
(0.1 watt) peak EIRP; the limitation on power spectral density to
a maximum of 0.03 milliwatts in any 3 kHz segment; the limitation
on height of outdoor antennas; and the "listen-before-talk"
protocol standard. There is no significant antenna gain
characteristic proposed to be permitted, though the Commission
seeks information on the appropriate regulation applied to
antennas.
4. Thus, the Commission has essentially adopted the concept
of short-range, high-speed networks proposed by WINForum in the
lower portion of the 5 GHz band, and proposed a full 200 MHz of
spectrum for use by Part 15 unlicensed NII/SUPERNet devices
therein at 5.15-5.35 GHz [1]. It has rejected in principle the
proposal of Apple Computer for long-range, high power unlicensed
devices. Notwithstanding the proper rejection of the concept of
15 km path lengths from Part 15 unlicensed devices in shared
bands, the Commission nonetheless proposes to permit lower power
devices to operate in an additional 150 MHz of spectrum at 5.725-
5.875 GHz, to conduct the same types of communications that would
be conducted in the 200 MHz of spectrum at 5.15-5.35 GHz.
5. The Notice is silent as to the Commission's rationale for
the necessity of the additional frequency authorization for
NII/SUPERNet Part 15 devices in the upper 150 MHz, except to say
that "(w)e also believe that the 5.725-5.875 GHz band is
appropriate spectrum for NII/SUPERNet operations and that with
appropriate technical constraints, these devices can share with
existing amateur, unlicensed and ISM operations, as well as with
FSS uplinks in the 5.850-5.875 GHz band." It is not clear that
the Commission substantively addressed the contention of
commenters such as Andrew Corporation, which, in response to the
two petitions for rule making, supported the use of the lower
portion of the 5 GHz band for NII/SUPERNet devices, but stated
that the need to make available more than 150 MHz for such
devices now is far too speculative to warrant the disruption of
existing services at 5.8 GHz. The League agreed with that prudent
warning then, and agrees with it now: unless and until the
Commission determines the adequacy and sufficiency of the 5.15-
5.35 GHz band for NII/SUPERNet devices, it should not make the
5.725-5.875 GHz segment available.
III. The Commission Has Pushed The Part 15 Concept
As Far As It Can Go
6. The League, in its comments in RM-8653, suggested not
only that the Apple proposal for NII use of 5.7 GHz was
premature, it misunderstood the entire regulatory framework for
Part 15 unlicensed devices:
The concept of "community networks" and local area
networks as Apple proposes appears better facilitated
by the use of existing services such as private, fixed
point-to-point microwave facilities now licensed by the
Commission under Part 94; by frequencies above 40 GHz;
by licensed and unlicensed PCS facilities for which the
Commission has just allocated a substantial amount of
spectrum at and near 2 GHz; and by existing wireline
facilities... Part 15 operation is itself questionable
under the terms of the present Communications Act; an
allocation for unlicensed communications devices as
proposed by Apple would be plainly impermissible. Part
15 devices have no allocation status, and have had
none, internationally or domestically... These devices
are permitted on an "at-sufferance" basis: they must
not cause interference to licensed radio services, and
they must tolerate interference received from licensed
radio services in the same bands. The Communications
Act of 1934 is devoid of any authority to accord Part
15 ... devices any allocation status at all; the only
authority to permit unlicensed devices under the Act is
with respect to radio control and citizen's radio
service facilities. 47 U.S.C. 307(e). The only
provision for Part 15 devices in the Communications Act
is for the Commission to regulate the interference
potential of such devices by "reasonable regulation".
47 U.S.C. 302. This the Commission has done by
permitting operation of such devices in bands
allocated, on a primary basis, to one or more licensed
radio services, where the operation of the unlicensed
devices has been determined to be unlikely to cause
interference to the licensed radio services. [2]
7. The instant Notice proposal would permit wireless
interconnection of computers into local area networks over short
distances of several hundred yards, at power levels and
bandwidths that are presumptively unlikely to cause significant
interference to amateur or other communications, except in quite
close geographic proximity. The main problem is the ubiquitous
nature of the devices, their mobility, and the potential
aggregate interference potential, which has not yet been
determined. Thus, whether the NII/SUPERNet devices can operate in
the same environment as amateur radio at 5.725-5.875 GHz is
unclear. This is a significant additional basis for presently
limiting the authorization of the devices to the 5.15-5.35 GHz
band. The League would be willing and able to conduct sharing
studies with manufacturers of the devices in the near term to
determine whether NII/SUPERNet devices could conform to Part 15
concepts and still be useful consistent with interference
susceptibility, and the overall compatibility of NII/SUPERNet
devices with co-channel amateur operation.
8. Assuming, however, that the Commission decides to proceed
with the 5.725-5.875 GHz authorization at present, the technical
rules proposed would have to be strictly adhered to, in order to
protect licensed radio services with allocations in the subject
bands from interference. The proposed General Technical
Requirements, Section 15.407 in the proposed Appendix to the
Notice, sets forth reasonable criteria which could be assumed to
permit minimal interaction with amateur communications. This
proposal, however, is as far as the Commission could go with the
Part 15 unlicensed device concept. To permit either greater
transmitter power than one-tenth of a watt, or to permit high-
gain antennas for non-spread-spectrum devices in the subject band
would signal a significant departure from the conceptual
framework for Part 15 unlicensed devices. Part 15 and Part 18
devices are permitted under present rules to operate at
relatively limited field strengths and operate over very short
range, thus to protect licensed services against interference; [3]
only spread-spectrum devices are permitted to operate at up to
one watt of power, as the result of the reduced interference
potential from true spread-spectrum systems to narrowband co-
channel services. As to adherence to the technical rules
proposed, the Commission can be assured of no voluntary rule
compliance; the marketing of Part 15 devices is as a general
matter not confidence inspiring, when one considers the marketing
rules violations and the inability or unwillingness of the
Commission to police these violations. It could be expected that
the NII/SUPERNet devices would be marketed in configurations in
excess of authorized parameters. Because of the interservice
interference potential and the proliferation of the devices, and
because control over unlicensed facilities is non-existent,
higher-power devices must be licensed devices.
9. Notwithstanding the stated concern that "permitting
higher power, longer range links would pose unacceptable
interference risks to other services..." the Commission notes
that it finds "merit in the concept of longer range community
networks and seek(s) comment on whether to permit such higher
power operation at up to 1 watt of transmitter output power
within the 5.725-5.875 GHz band." Such is ill-advised and would
go well beyond the Commission's authority, since non-spread-
spectrum devices, with no bandwidth limitations, at significant
power and antenna gain, operating over the 15 km paths that Apple
envisions, are not compatible with co-channel amateur operation.
Purely and simply, higher powered transmitters and high antenna
gain have significant interference potential and must, under the
regulatory requirements of the Communications Act, be operated on
a licensed basis. Any interconnection of schools, for example, as
Apple proposes, should be done through 2 GHz PCS facilities,
millimeter-wave facilities, licensed, fixed point-to-point
microwave facilities, or via cable systems or the public switched
telephone network. Furthermore, it would appear to the League
incompatible to mix the lower power, unlicensed NII/SUPERNet
devices with higher power unlicensed community networks in the
same bands; the intermixture would frustrate the entire concept
of short range localized communications.
10. Taking into account the virtual absence of any
enforcement activity of the Commission, in recent years, in non-
safety-of-life interference incidents, and the anticipated
continuation of the problem in the near future, it would be
entirely inappropriate (even assuming that unlicensed operation
at higher power with high-gain antennas was possible as a matter
of law), to authorize such. The interaction that would inevitably
result from co-channel amateur operation would never be resolved
as a matter of fact, and the absence of any regulatory priority
of such devices relative to licensed services is not an adequate
explanation in the minds of the consumers of such devices.
IV. The Proposed Rules for NII/SUPERNet Devices
Appear To Be Sufficient to Avoid Significant Interference
To the Amateur Service, But Sharing Studies are Necessary
11. While, as noted above, the ubiquitous nature of
NII/SUPERNet devices makes it difficult to determine the
aggregate interference potential of these devices relative to the
Amateur Service, the operational limitations proposed in the
Notice, and only those, taken together, [4] appear to be facially
sufficient to avoid significant interference to present and
future amateur service communications generally. These include
the following:
A) Limitation of peak EIRP to -10dBW (0.1 watt).
B) Limitation of power spectral density of 0.03 mW in any 3 kHz
bandwidth as measured with a spectrum analyzer.
C) Typical communications distances of 50 to 100 meters.
D) Attenuation of emissions outside the band of operation by 50
dB below the fundamental emission or as per existing Part
15 requirements.
E) Compliance with ANSI/IEEE 1992 RF Exposure standard.
F) Spectrum etiquette provisions of Proposed Section 15.411.
G) Antenna limitations for presumption of non-interference to
licensed services: either indoor antennas or outdoor antennas
not higher than 15 meters above ground.
H) Requirement of automatic discontinuation of transmission in
absence of information to transmit or operational failure.
12. Thus, while the League does not agree at all with the
Commission that there is any demonstrated need to permit
NII/SUPERNet devices to operate in both the 5.15-5.35 GHz and the
5.725-5.875 GHz bands at the present time, and suggests that the
lower segment is ample spectrum space to launch the concept in
the United States, the League does not take significant issue
with the Commission that, "with appropriate technical constraints
these devices can share with existing amateur, unlicensed and ISM
operations as well as with FSS uplinks...". It must be noted,
however, that these technical constraints have not yet been
developed and do not now exist.
13. NTIA has recommended, and the League heartily concurs,
that additional studies of spectrum sharing should be (and should
have been) conducted between the proposed unlicensed operations
and existing and proposed operations in the subject bands
(Notice, at paragraph 35). The League remains willing and able to
conduct sharing studies with Apple Computer or others as to the
feasibility of compatible sharing with amateurs at 5.725-5.875
GHz. Such studies should be conducted before any decision is made
with respect to 5.725-5.875 GHz. The burden of conducting such
studies should be on the proponents of the authorization, and at
least preliminary studies by those proponents should have
preceded the filing of their petitions, or at least prior to the
issuance of the Commission's Notice in this proceeding. It is
rather late on, procedurally, for the Commission to ask for
sharing studies to be conducted in the time available between the
issuance of the Notice and the comment dates.
14. This proceeding points up one of the flaws inherent in
the notice-and-comment process presently utilized with respect to
spectrum allocations issues; it does not mandate that the
proponent of a new use or an allocation change make at least
preliminary technical investigation of compatibility with
existing users. What has resulted from the failure of the
petitioners in this proceeding to do exactly that is that the
Commission itself has had to cobble together technical rules for
NII/SUPERNet devices based largely on assumptions of interference
potential. While it has done in this instance a creditable job, a
more scientific approach is called for in this, and in future
allocations proceedings.
V. Conclusions
15. In this proceeding, the Commission has proposed only to
permit short-range, wideband Part 15, unlicensed wireless LAN
devices to interconnect computer systems as part of the NII. It
has specifically not proposed, but it did request comment on,
long-range, higher power, non-spread-spectrum devices of the same
type, also unlicensed, for community networks. The Notice
proposal, including all of its interference avoidance elements,
is in keeping with the regulatory scheme for unlicensed devices,
though it pushes the regulatory premises for unlicensed operation
as far as they will conceptually go. The long-range, high powered
devices and path distances of 15 km do not provide a proper
framework for Part 15 devices. Such should be licensed
transmitters, operated as fixed, point-to-point microwave links
on a licensed basis, or provided alternatively through PCS
carriers or switched telephone services. An unlicensed radio
service with the characteristics proposed by Apple Computer is
ill-advised, and not in accordance with the licensing
requirements of the Communications Act of 1934.
16. The League sees no need, given the Commission's
proposal, for the availability of both the 5.15-5.35 GHz and the
5.725-5.875 GHz bands for NII/SUPERNet devices. The lower 200 MHz
is ample for development of NII systems. Use of the upper segment
would place a large number of these devices, with unknown
aggregate interference potential, in close geographic proximity
to co-channel amateur operations.
17. Should the Commission decide nonetheless to permit
NII/SUPERNet devices in the upper segment as well as the lower,
the League suggests that the Commission's proposed technical
operational rules and interference avoidance criteria, only if
taken together (and if strictly enforced), might be sufficient to
avoid widespread interference to amateur communications in the
5.650-5.925 GHz band. This cannot be confirmed, however, since
the proponents of the authorization have not conducted sharing
studies in advance of their proposal, nor has there been
sufficient time following the release of the Notice to do such.
As suggested by NTIA and others, such is desirable in advance of
formal rule making in this proceeding and in other allocations
proceedings.
Therefore, the foregoing considered, the American Radio
Relay League, Incorporated, requests that the Commission take no
further action toward Part 15 use of the 5.725-5.875 GHz band
except in accordance with these comments.
Respectfully submitted,
THE AMERICAN RADIO RELAY
LEAGUE, INCORPORATED
225 Main Street
Newington, CT 06111
By __________________________
Christopher D. Imlay
General Counsel
BOOTH, FRERET & IMLAY
1233 20th Street, N. W.
Suite 204
Washington, D. C. 20036
(202) 296-9100
July 15, 1996
_______________________________
[1] See, the Notice, at Paragraph 34.
[2] The Telecommunications Act of 1996, Pub. L. 104-104, 110
Stat. 56, Feb. 8, 1996, amended Section 307(e) of the
Communications Act of 1934 to add to those services which may by
FCC rule operate without individual licenses the aviation radio
service for aircraft stations operated on domestic flights when
such aircraft are not otherwise required to carry a radio
station; and the maritime radio service for ship stations
navigated on domestic voyages when such ships are not otherwise
required to carry a radio station.
[3] The Notice, at Paragraph 47, states that the instant
proposal would permit operation of NII/SUPERNet devices at
approximately 21 dB EIRP higher than existing, non-spread-
spectrum Part 15 intentional radiators in the 5.725-5.875 GHz
band.
[4] The League would emphasize that only these measures
together appear sufficient to mitigate interference; none are
sufficient alone, or in combination with less than all of the
listed items.