[Federal Register Volume 73, Number 211 (Thursday, October 30, 2008)]
[Rules and Regulations]
[Pages 64558-64562]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-25802]


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FEDERAL COMMUNICATIONS COMMISSION

47 CFR Part 73

[MM Docket No. 93-177; FCC 08-228]


An Inquiry Into the Commission's Policies and Rules Regarding AM 
Radio Service Directional Antenna Performance Verification

AGENCY: Federal Communications Commission.

ACTION: Final rule.

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SUMMARY: In this proceeding the Commission permits the use of computer 
modeling techniques to verify that directional AM antennas perform as 
authorized. The new rules reduce the time and expense associated with 
the license application for a directional AM station. The changes, 
consistent with the Commission's streamlining initiatives, reduce the 
regulatory burden upon directional AM stations to the extent possible 
while maintaining the integrity of the service.

DATES: Effective December 1, 2008, except for the amendments to 
Sec. Sec.  73.61, 73.68, 73.151, and 73.155 which contain information 
collection requirements that have not been approved by Office of 
Management and Budget (OMB). The Commission will publish a document in 
the Federal Register announcing the effective date of these rules.

ADDRESSES: Secretary, Federal Communications Commission, 445 12th 
Street, SW., Washington, DC 20554, http://www.fcc.gov.

FOR FURTHER INFORMATION CONTACT: Peter H. Doyle, Audio Division, Media 
Bureau (202) 418-2700.

SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Second 
Report and Order in MM Docket No. 93-177, adopted September 24, 2008, 
and released September 26, 2008. The new rules adopted here were 
proposed in an earlier Further Notice of Proposed Rule Making in this 
proceeding [See 66 FR 20779, April 25, 2001]. The final rules 
incorporate comments received in response to the Further Notice of 
Proposed Rule Making. The complete text of this Second Report and Order 
is available for inspection and copying during normal business hours in 
the FCC Reference Center (Room CY-A257), 445 12th Street, SW., 
Washington, DC

[[Page 64559]]

and may also be purchased from the Commission's copy contractor, Best 
Copy and Printing, Inc., (800) 378-3160, 445 12th Street, SW., Room CY-
402, Washington, DC 20554. The complete text is also available on the 
Internet at http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-08-228A1.pdf.

Synopsis of Second Report and Order

    1. Introduction. This proceeding is part of a broad-based 
initiative to simplify the Commission's licensing procedures for radio 
stations. The Report and Order in this proceeding [See 66 FR 20752, 
April 25, 2001] simplified traditional proof of performance 
requirements for a directional AM station. The Further Notice of 
Proposed Rulemaking sought comment on the use of moment method computer 
modeling to demonstrate that certain AM directional antennas perform as 
authorized. This Second Report and Order permits AM broadcasters to use 
computer modeling techniques in place of a traditional proof of 
performance based on field strength measurements, which are time-
consuming and expensive.
    2. AM proof of performance requirements. Directional AM stations 
use antennas which suppress radiated field in some directions and 
enhance it in others. In order to control interference between stations 
and assure adequate community coverage, directional AM stations must 
undergo extensive ``proofs of performance'' to demonstrate that the 
antenna system operates as authorized. An antenna proof of performance 
establishes whether the radiation pattern of an AM station is in 
compliance with the station's authorization. An AM station must perform 
a full proof to verify the pattern shape when a new directional antenna 
system is authorized. Partial proofs, which require fewer measurements, 
are occasionally necessary to show that an array continues to operate 
properly. This Second Report and Order allows most directional AM 
stations to use computer modeling in place of the traditional proof of 
performance, which is based on field strength measurements taken many 
miles from the antenna. In contrast to the traditional method, a moment 
method proof relies upon internal measurements to verify that the 
antenna is operating properly.
    The new rules are based on a proposal made by an ad hoc coalition 
of radio broadcasters, equipment manufacturers, and broadcast 
consulting engineers. Comments filed by the ad hoc coalition reflected 
a strong consensus in favor of allowing the use of moment method 
techniques to verify the performance of AM directional antennas. In 
addition, the coalition's comments pointed out some of the limitations 
inherent in traditional field strength proofs.

Final Regulatory Flexibility Analysis

    As required by the Regulatory Flexibility Act of 1980, as amended 
(RFA),\1\ an Initial Regulatory Flexibility Analysis (IRFA) was 
incorporated in the Further Notice of Proposed Rulemaking in this 
proceeding. The Commission sought written public comment on the 
proposals in the Further Notice of Proposed Rulemaking, including 
comment on the IRFA. None were received. This Final Regulatory 
Flexibility Analysis (FRFA) conforms to the RFA.\2\
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    \1\ See 5 U.S.C. 603. The RFA, see 5 U.S.C. 601 et seq., has 
been amended by the Small Business Regulatory Enforcement Fairness 
Act of 1996 (SBREFA), Public Law No. 104-121, Title II, 110 Stat. 
847 (1996). The SBREFA was enacted as Title II of the Contract With 
America Advancement Act of 1996.
    \2\ See 5 U.S.C. 604.
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    Need For and Objectives of the Rules: This Second Report and Order 
adopts rules permitting the use of computer modeling techniques based 
on moment method analysis to verify AM directional antenna performance. 
Adoption of such techniques will reduce the substantial costs 
associated with licensing for directional AM stations. These rules also 
advance the Commission's regulatory requirements to the minimum 
necessary to achieve our policy objectives of controlling interference 
and assuring adequate community coverage.
    Legal Basis: Authority for the actions proposed in this Second 
Report and Order may be found in sections 4(i), 4(j), 303, 308, 309, 
316 and 319 of the Communications Act of 1934, as amended, 47 U.S.C. 
154(i), 154(j), 303, 308, 309, 316 and 319.
    Description and Estimate of the Number of Small Entities to Which 
the Proposed Rules Will Apply: The RFA directs the Commission to 
provide a description of and, where feasible, an estimate of the number 
of small entities that will be affected by the rules adopted herein.\3\ 
The RFA generally defines the term ``small entity'' as having the same 
meaning as the terms ``small business,'' ``small organization,'' and 
``small government jurisdiction.'' \4\ In addition, the term ``small 
business'' has the same meaning as the term ``small business concern'' 
under the Small Business Act.\5\ A small business concern is one which: 
(1) Is independently owned and operated; (2) is not dominant in its 
field of operation; and (3) satisfies any additional criteria 
established by the Small Business Administration (SBA).\6\
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    \3\ 5 U.S.C. 603(b)(3).
    \4\ 5 U.S.C. 601(6).
    \5\ 5 U.S.C. 601(3) (incorporating by reference the definition 
of ``small business concern'' in 15 U.S.C. 632). Pursuant to 5 
U.S.C. 601(3), the statutory definition of a small business applies 
``unless an agency, after consultation with the Office of Advocacy 
of the Small Business Administration and after opportunity for 
public comment, establishes one or more definitions of such term 
which are appropriate to the activities of the agency and publishes 
such definition(s) in the Federal Register.'' 5 U.S.C. 601(3).
    \6\ 15 U.S.C. 632.
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    The rules adopted in this Second Report and Order will apply to 
those AM radio broadcasting licensees and potential licensees that 
operate with directional antennas. The Small Business Administration 
defines a radio broadcasting entity that has $6.5 million or less in 
annual receipts as a small business.\7\ Business concerns included in 
this industry are those ``primarily engaged in broadcasting aural 
programs by radio to the public.'' According to Commission staff review 
of the BIA Financial Network, Inc. Media Access Radio Analyzer Database 
as of May 1, 2008, 13,457 (about 96 percent) of 13,977 radio stations 
in the United States have revenues of $6.5 million or less. AM stations 
constitute 4,776 of the radio station total, and approximately 40 
percent of AM stations use directional antennas. Consequently, we 
estimate that 1,910 AM stations may be affected by the new rules. Using 
the 96 percent figure to estimate the number of small businesses among 
directional AM stations, we conclude that approximately 1,834 of the 
affected AM stations are small businesses. We note, however, that in 
assessing whether a business entity qualifies as small under the above 
definition, business control affiliations \8\ must be included. Our 
estimate, therefore, likely overstates the number of small entities 
that might be affected by any changes to the ownership rules, because 
the revenue figures on which this estimate is based do not include or 
aggregate revenues from affiliated companies.
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    \7\ See NAICS Code 515112.
    \8\ ``[Business concerns] are affiliates of each other when 
onebusiness concern controls or has the power to control the other 
or a third party or parties controls or has the power to control 
both.'' 13 CFR 121.103(a)(1).
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    In this context, the application of the statutory definition to 
radio stations is of concern. An element of the definition of ``small 
business'' is that the entity not be dominant in its field of 
operation. We are unable at this time and in this context to define or 
quantify the criteria that would establish whether a specific

[[Page 64560]]

radio station is dominant in its field of operation. Accordingly, the 
foregoing estimate of small businesses to which the rules may apply 
does not exclude any radio station from the definition of a small 
business on this basis and is therefore over-inclusive to that extent. 
An additional element of the definition of ``small business'' is that 
the entity must be independently owned and operated. We note that it is 
difficult at times to assess these criteria in the context of media 
entities, and our estimates of small businesses to which they apply may 
be over-inclusive to this extent.
    Description of Projected Recording, Recordkeeping, and Other 
Compliance Requirements: In order to control interference between 
stations and assure adequate community coverage, directional AM 
stations must undergo extensive ``proofs of performance'' when 
initially constructed, and from time to time thereafter, to verify 
conformance with authorized operating parameters. The new proof of 
performance techniques adopted here, which are optional, will 
substantially reduce the compliance burden for licensees of directional 
AM stations and for Commission staff. The new compliance requirements 
associated with the rule changes are less onerous than our existing 
proof of performance requirements. The periodic recertification 
required for stations opting to use the new proof of performance 
techniques is the only new record keeping involved. We believe this 
requirement does not represent a significant burden, and is more than 
offset by the efficiency of the new procedures.
    Steps Taken To Minimize Significant Economic Impact on Small 
Entities and Significant Alternatives Considered: The RFA requires an 
agency to describe any significant alternatives that it has considered 
in reaching its proposed approach, which may include the following four 
alternatives (among others): (1) The establishment of differing 
compliance or reporting requirements or timetables that take into 
account the resources available to small entities; (2) the 
clarification, consolidation, or simplification of compliance or 
reporting requirements under the rule for small entities; (3) the use 
of performance, rather than design, standards; and (4) an exemption 
from coverage of the rule, or any part thereof, for small entities.\9\
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    \9\ 5 U.S.C. 603(c)(1) through (c)(4).
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    The rules adopted in the Second Report and Order offer alternative 
procedures that will greatly reduce the compliance burden for 
directional AM stations. Directional AM stations are not required to 
use these new procedures, however. Previous rules concerning AM 
directional antenna performance verification remain in effect, and an 
AM station may continue to use the old rules if these are more 
advantageous. By offering a cost-effective and efficient new means of 
performance verification, but not requiring its use, we have increased 
the options available to all directional AM stations for verifying 
antenna performance. The additional flexibility afforded by the new 
rules will be particularly advantageous to small businesses.

Paperwork Reduction Act Analysis

    The Second Report and Order contains new and modified information 
collection requirements subject to the paperwork Reduction Act of 1995 
(PRA), Public Law 104-13. In addition, it contains new and modified 
``information collection burdens for small business concerns with fewer 
than 25 employees,'' pursuant to the Small Business Paperwork Relief 
Act of 2002, Public Law 107-198, see 44 U.S.C. 3506(c)(4). It will be 
submitted to the Office of Management and Budget (OMB) for review under 
section 3507(d) of the PRA. The Commission, as part of its continuing 
effort to reduce paperwork burdens, will invite the general public and 
OMB in a separate Federal Register to comment on the information 
collection requirements contained in this document, as required by the 
Paperwork Reduction Act of 1995. In regard to the proposed new 
information collection requirements, pursuant to the Small Business 
Paperwork Relief Act of 2002,\10\ we seek specific comment on how we 
might ``further reduce the information collection burden for small 
business concerns with fewer than 25 employees.'' In regard to the new 
and modified information collection requirements adopted herein, we 
previously sought specific comment on how the Commission might 
``further reduce the information collection burden for small business 
concerns with fewer than 25 employees.'' In the Second Report and 
Order, we have assessed the effects of the new rules for directional AM 
performance verification adopted herein, and find that these new rules, 
which are optional, would greatly reduce the information collection 
burden for licensees.
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    \10\ Public Law 107-198, see 44 U.S.C. 3506(c)(4).
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Report to Congress

    The Commission will send a copy of the Second Report and Order and 
Second Further Notice of Proposed Rulemaking, including the FRFA, in a 
report to be sent to Congress and the Government Accountability Office 
pursuant to the Congressional Review Act.\11\ In addition, the 
Commission will send a copy of the Second Report and Order and Second 
Further Notice of Proposed Rulemaking, including the FRFA, to the Chief 
Counsel for Advocacy of the Small Business Administration. A copy of 
the Second Report and Order and Second Further Notice of Proposed 
Rulemaking, including the FRFA (or summaries thereof), will also be 
published in the Federal Register.\12\
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    \11\ See 5 U.S.C. 801(a)(1)(A).
    \12\ See 5 U.S.C. 604(b).
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List of Subjects

    Radio.

Federal Communications Commission.
Marlene H. Dortch,
Secretary.

Rules Changes

0
For the reasons discussed in the preamble, the Federal Communications 
Commission amends 47 CFR part 73 to read as follows:

PART 73--RADIO BROADCAST SERVICES

0
1. The authority citation for part 73 continues to read as follows:

    Authority: 47 U.S.C. 154, 303, 334, 336, and 339.


0
2. Amend Sec.  73.61 by revising paragraphs (a) and (b) to read as 
follows:


Sec.  73.61  AM directional antenna field strength measurements.

    (a) Each AM station using a directional antenna with monitoring 
point locations specified in the instrument of authorization must make 
field strength measurements as often as necessary to ensure that the 
field at each of those points does not exceed the value specified in 
the station authorization. Additionally, stations not having an 
approved sampling system must make the measurements once each calendar 
quarter at intervals not exceeding 120 days. The provision of this 
paragraph supersedes any schedule specified on a station license issued 
prior to January 1, 1986. The results of the measurements are to be 
entered into the station log pursuant to the provisions of Sec.  
73.1820.

[[Page 64561]]

    (b) If the AM license was granted on the basis of field strength 
measurements performed pursuant to Sec.  73.151(a), partial proof of 
performance measurements using the procedures described in Sec.  73.154 
must be made whenever the licensee has reason to believe that the 
radiated field may be exceeding the limits for which the station was 
most recently authorized to operate.
* * * * *

0
3. Amend Sec.  73.68 by revising paragraph (a), redesignating 
paragraphs (b) through (e) as paragraphs (c) through (f), and by adding 
a new paragraph (b) to read as follows:


Sec.  73.68  Sampling systems for antenna monitors.

    (a) Each AM station permittee authorized to construct a new 
directional antenna system which will be subject to a proof of 
performance based on field strength measurements, as described in Sec.  
73.151(a) or (b), must install the sampling system in accordance with 
the following specifications:
    (1) Devices used to extract or sample the current and the 
transmission line connecting the sampling elements to the antenna 
monitor must provide accurate and stable signals to the monitor (e.g., 
rigidly mounted and non-rotatable loops and all system components 
protected from physical and environmental disturbances).
    (2) Sampling lines for directional antennas may be of different 
lengths provided the phase difference of signals at the monitor are 
less than 0.5 degrees between the shortest and longest cable lengths 
due to temperature variations to which the system is exposed.
    (3) Other configurations of sampling systems may be used upon 
demonstration of stable operation to the FCC.
    (b) An AM station permittee authorized to construct a directional 
antenna system which will be subject to a proof of performance based on 
moment method modeling, as described in Sec.  73.151(c), shall install 
a sampling system conforming to the requirements set forth in that 
section.
* * * * *

0
4. Amend Sec.  73.151 by adding introductory text and by adding 
paragraph (c) to read as follows:


Sec.  73.151  Directional Antenna Performance Verification.

    The performance of a directional antenna may be verified either by 
field strength measurement or by computer modeling and sampling system 
verification.
    (a) * * *
* * * * *
    (c) Computer modeling and sample system verification of modeled 
parameters to establish operation of a directional antenna consistent 
with the theoretical pattern. Each element of the directional array 
shall be modeled by use of a method of moments computer program, using 
the physical characteristics of each element to establish a model that 
does not violate any of the internal constraints of the computer 
program. Only arrays consisting of series-fed elements may have their 
performance verified by computer modeling and sample system 
verification.
    (1) A matrix of impedance measurements at the base and/or feed 
point of each element in the array, with all other elements shorted 
and/or open circuited at their respective measurement locations, shall 
be made. The physical model of the individual antenna elements used in 
the computer program may be varied to match the measured impedance 
matrix, but the actual spacings and orientations of the array elements 
must be used. Towers may be modeled using individual vertical wires to 
represent them, or with multiple wires representing their leg and 
cross-member sections. The resulting model description (consisting of 
the length, radius, and number of segments of each wire for arrays 
using vertical wire sections to represent the towers, or the length, 
end-point coordinates, and radius of each wire used to represent leg 
and cross-member sections for arrays using detailed tower structure 
representations) as well as the assumed input feed and base region 
stray reactances shall be used to generate the drive impedances and 
sample system parameter values for the operating directional antenna 
pattern parameters.
    (i) For arrays using vertical wires to represent each tower, the 
radii of cylinders shall be no less than 80 percent and no more than 
150 percent of the radius of a circle with a circumference equal to the 
sum of the widths of the tower sides.
    (ii) For arrays using multiple wires to represent leg and cross-
member sections, the individual legs of the tower may be modeled at 
their actual diameters with appropriate interconnecting segments 
representing cross-members at regular intervals.
    (iii) No less than one segment for each 10 electrical degrees of 
the tower's physical height shall be used for each element in the 
array.
    (iv) Base calculations shall be made for a reference point at 
ground level or within one electrical degree elevation of the actual 
feed point.
    (v) For uniform cross-section towers represented by vertical wires, 
each wire used for a given tower shall be between 75 to 125 percent of 
the physical length represented.
    (vi) For self-supporting towers, stepped-radius wire sections may 
be employed to simulate the physical tower's taper, or the tower may be 
modeled with individual wire sections representing the legs and cross 
members.
    (vii) The lumped series inductance of the feed system between the 
output port of each antenna tuning unit and the associated tower shall 
be no greater than 10 [mu]H unless a measured value from the 
measurement point to the tower base with its insulator short circuited 
is used.
    (viii) The shunt capacitance used to model base region effects 
shall be no greater than 250 pF unless the measured or manufacturer's 
stated capacitance for each device other than the base insulator is 
used. The total capacitance of such devices shall be limited such that 
in no case will their total capacitive reactance be less than five 
times the magnitude of the tower base operating impedance without their 
effects being considered.
    (ix) The orientation and distances among the individual antenna 
towers in the array shall be confirmed by a post-construction 
certification by a land surveyor (or, where permitted by local 
regulation, by an engineer) licensed or registered in the state or 
territory where the antenna system is located.
    (2)(i) The computer model, once verified by comparison with the 
measured base impedance matrix data, shall be used to determine the 
appropriate antenna monitor parameters. The moment method modeled 
parameters shall be established by using the verified moment method 
model to produce tower current distributions that, when numerically 
integrated and normalized to the reference tower, are identical to the 
specified field parameters of the theoretical directional antenna 
pattern. The samples used to drive the antenna monitor may be current 
transformers or voltage sampling devices at the outputs of the antenna 
matching networks or sampling loops located on the towers. If sample 
loops are used, they shall be located at the elevation where the 
current in the tower would be at a minimum if the tower were detuned in 
the horizontal plane, as determined by the moment method model 
parameters used to determine the antenna monitor parameters. Sample 
loops may be employed only when the towers are

[[Page 64562]]

identical in cross-sectional structure, including both leg and cross 
member characteristics; if the towers are of unequal height, the sample 
loops shall be mounted identically with respect to tower cross members 
at the appropriate elevations above the base insulator. If the tower 
height used in the model is other than the physical height of the 
tower, the sampling loop shall be located at a height that is the same 
fraction of the total tower height as the minimum in tower current with 
the tower detuned in the model. Sample lines from the sensing element 
to the antenna monitor must be equal in both length (within one 
electrical degree) and characteristic impedance (within two ohms), as 
established by impedance measurements, including at the open-circuit 
resonant frequency closest to carrier frequency to establish length, at 
frequencies corresponding to odd multiples of \1/8\ wavelength 
immediately above and below the open circuit resonant frequency closest 
to carrier frequency, while open circuited, to establish characteristic 
impedance, and at carrier frequency or, if necessary, at nearby 
frequencies where the magnitude of the measured impedance is no greater 
than 200 ohms with the sampling devices connected. Samples may be 
obtained from current transformers at the output of the antenna 
coupling and matching equipment for base-fed towers whose actual 
electrical height is 120 degrees or less, or greater than 190 
electrical degrees. Samples may be obtained from base voltage sampling 
devices at the output of the antenna coupling and matching equipment 
for base-fed towers whose actual electrical height is greater than 105 
degrees. Samples obtained from sample loops located as described above 
can be used for any height of tower. For towers using base current or 
base voltage sampling derived at the output of the antenna coupling and 
matching equipment, the sampling devices shall be disconnected and 
calibrated by measuring their outputs with a common reference signal (a 
current through them or a voltage across them, as appropriate) and the 
calibration must agree within the manufacturer's specifications. A 
complete description of the sampling system, including the results of 
the measurements described in this paragraph, shall be submitted with 
the application for license.
    (ii) Proper adjustment of an antenna pattern shall be determined by 
correlation between the measured antenna monitor sample indications and 
the parameters calculated by the method of moments program, and by 
correlation between the measured matrix impedances for each tower and 
those calculated by the method of moments program. The antenna monitor 
sample indications must be initially adjusted to agree with the moment 
method model within +/-5 percent for the field ratio and +/-3 degrees 
in phase. The measured matrix impedances must agree with the moment 
method model within +/-2 ohms and +/-4 percent for resistance and 
reactance.
    (3) Reference field strength measurement locations shall be 
established in directions of pattern minima and maxima. On each radial 
corresponding to a pattern minimum or maximum, there shall be at least 
three measurement locations. The field strength shall be measured at 
each reference location at the time of the proof of performance. The 
license application shall include the measured field strength values at 
each reference point, along with a description of each measurement 
location, including GPS coordinates and datum reference.

0
5. Add new Sec.  73.155 to read as follows:


Sec.  73.155  Periodic Directional Antenna Performance Recertification.

    A station licensed with a directional antenna pattern pursuant to a 
proof of performance using moment method modeling and internal array 
parameters as described in Sec.  73.151(c) shall recertify the 
performance of that directional antenna pattern at least once within 
every 24 month period.
    (a) Measurements shall be made to verify the continuing integrity 
of the antenna monitor sampling system.
    (1) For towers using base current or base voltage sampling derived 
at the output of the antenna coupling and matching equipment, the 
sampling devices shall be disconnected and calibrated by measuring 
their outputs with a common reference signal (a current through them or 
a voltage across them, as appropriate) and the calibration must agree 
with the manufacturer's specifications.
    (2) For towers using base current or base voltage sampling derived 
at the output of the antenna coupling and matching equipment, sampling 
line measurements shall be made to verify the open-circuit resonant 
frequency closest to carrier frequency, to establish length, and also 
at frequencies corresponding to odd multiples of \1/8\ wavelength 
immediately above and below the open-circuit resonant frequency closest 
to carrier frequency, while open circuited, to verify their 
characteristic impedance. The frequencies measured must be the same as 
were measured in the most recent proof of performance and must 
demonstrate that the sampling lines continue to meet the requirements 
of Sec.  73.151(c) with regard to their length and characteristic 
impedance.
    (3) For towers having sampling loops, measurements shall be made at 
carrier frequency or, if necessary, at nearby frequencies where the 
magnitude of the measured impedance is no greater than 200 ohms with 
the sampling loops connected. The frequencies measured must be the same 
as were measured in the most recent proof of performance and the 
measured impedances must agree within +/-2 ohms and +/-4 percent 
resistance and reactance of the proof values.
    (b) Field strength measurements shall be made at the reference 
field strength measurement locations that were established by the most 
recent proof of performance. If locations have become inaccessible or 
their readings contaminated by localized electromagnetic environmental 
changes, new locations that meet the requirements of the moment method 
proof of performance rules in Sec.  73.151(c)(3) shall be established 
to replace them.
    (c) The results of the periodic directional antenna performance 
recertification measurements shall be retained in the station's public 
inspection file.

[FR Doc. E8-25802 Filed 10-29-08; 8:45 am]
BILLING CODE 6712-01-P