FCC - Validation of test sites for radiated emission testing

Posted Aug. 22, 2024, a Petition for Rule-Making requesting to incorporate the newly adopted ANSI/USEMCSC C63.25.2-2024 standard, rules for the validation of test sites used for radiated emission testing between 30 MHz and 1 GHz., into FCC Title 47 Part 2 and Part 15.

The C63.25 standard series will consolidate site validation methods into a standard series for reference from within various test method standards (i.e. C63.4, C63.10 etc.). The series addresses the appropriate and required site validation for sites used when performing tests related to the applicable frequency range of measurement.

C63.25.1 - Validation Methods for Radiated Emission Test Sites, 1 GHz to 18 GHz

C63.25.2 - Validation Methods for Radiated Emission Test Sites, 30 MHz to 1 GHz

C63.25.3 - Validation Methods for Radiated Emission Test Sites, 18-40 GHz

The content of C63.25.2 consists of the traditional normalized site attenuation methods used for years and the addition of two new methods, a site comparison method (SCM) and delta NSA (DNSA) method. For more information and details on the new methods see reference below or obtain a copy of C63.25.2.

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Ref:

https://www.fcc.gov/ecfs/search/search-filings/filing/108210752429140

FCC Rule Change Focus on Vehicle and Airport Safety

English: Collision Warning with Brake Support (Photo credit: Wikipedia)

July 3, 2012, the FCC has amended Part 15 rules to enable enhanced vehicular radar technologies in the 76-77 GHz band, and to allow fixed radar applications at airports with an aim to improve safety for personnel and equipment.

The amendment includes a relaxation of limits for vehicular radar technologies, and is justified within the Report and Order, citing that maximum permissible limits for human exposure to RF electromagnetic fields had not been established at the time the rules were originally adopted (1995), and the original limits, intended to protect pedestrians in the proximity of stopped vehicles, are far more restrictive than the currently adopted RF exposure levels.

The modifications are applicable specifically to sections 15.35 and 15.253 of title 47 Part 15.

The amendment to section 15.35 eliminates the requirement that vehicular radars decrease power when the vehicle is not in motion. Furthermore this modification specifies a new relaxed emission limit for 76-77 GHz front, side, and rear illuminating vehicular radars. The FCC takes these actions in response to petitions filed by Toyota Motor Corporation (TMC) and Era Systems Corporation (Era).

The modification of section 15.253 will allow fixed radar systems operating in the 76-77 GHz band to be installed at airport locations. These systems are used for foreign object debris (FOD) detection on runways as well as the ability to monitor aircraft and service vehicle traffic on the taxiways and other non-public ground locations.

The FCC justifies these modifications within the Report and Order claiming they “will provide more efficient use of the spectrum, and enable the automotive and aviation industries to develop enhanced safety measures for drivers and the general public”.

The 76-77 GHz band is considered Extremely High Frequency (EHF), and is within the “W band”, 75 GHz to 119 GHz. The EHF spectrum is what is commonly referred to as the millimeter wave spectrum, which is considered to begin at 30 GHz and end at 300 GHz.

The 76-77 GHz band is primarily allocated to the Radio Astronomy Service (RAS) and the Radiolocation service. Amateur and Space research (space-to-Earth) services utilize this band on a secondary basis.

The National Radio Astronomy Observatory (NRAO) and National Academy of Sciences’ Committee on Radio Frequencies (CORF) has raised concerns about increased interference potential to radio astronomy operations if the rules are adopted. NRAO argues that vehicular radars may interfere with radio astronomy receivers over distances up to approximately 60 miles. NRAO states that “destruction of radio astronomy receivers is a serious possibility” due to the high powered vehicular radars. The Automotive industry disagrees with the claims citing that they are speculative. The FCC notes that vehicular radar has been permitted in the 76-77 GHz band since 1995, and that an increase in potential interference as a result of the rule change is negligible.

Ref:

FCC Report and Order

NPRM ET Docket No. 11-90

Era Systems Corp. 2.803, 15.201, 15.253 waiver request and FCC response

Wireless handset hearing aid compatibility standard adopted

Hearing aid types (300dpi) (Photo credit: Wikipedia)

The FCC has formally adopted ANSI C63.19 2011 as an applicable technical standard for evaluating the hearing aid compatibility of wireless phones.

As specified in the Second Further Notice, the new rules permit the use of either ANSI C63.19 2007, or ANSI C63.19 2011  for the testing of new handset models. All existing grants issued under the 2007 standard, as well as any pre-2010 grants remain valid, thus, no existing handset models will require retesting or recertification for hearing aid compatibility.

A 12 month transition period has been adopted for testing of multi-band and multi-mode handsets that incorporate operations which are not covered under the 2007 ANSI Standard. The Report and Order recognizes that as the new rules become effective, some manufacturers will be in production cycles where it will be impractical to return to a testing cycle for upcoming multi-band or multi-mode handsets under the 2011 ANSI Standard. Specifically, during the transition period, and as an alternative to using the 2011 standard, manufacturers may certify handsets as hearing aid compatible if they meet all compatibility criteria under the 2007 ANSI standard for all operations covered by that standard, providing they meet the disclosure requirements set forth in the order. After the transition period, all new handsets that contain operations not covered by the 2007 version will need to comply with the 2011 ANSI standard.

The Report and Order makes it clear that evaluations performed partly under one version of the ANSI standard, and partly under another, is incompatible with existing rules, thus manufacturers must test exclusively with one of the applicable versions.

Ref;

http://transition.fcc.gov/Daily_Releases/Daily_Business/2012/db0409/DA-12-550A1.pdf

http://www.emcrules.com/2011/11/hearing-aid-compatibility-for-wireless.html

FCC updates answer for exempt appliances

하상림 작가의 꽃 디자인이 적용된 냉장고와 김희애 (Photo credit: Wikipedia)

Under Title 47, Part 15.103,  digital devices used exclusively in an appliance are exempt from the specific technical standards and other requirements of part 15. Seems simple enough, if it’s an appliance, then it’s exempt from FCC testing. So a vacuum cleaner is exempt from FCC testing, correct? How about an electric blanket? A hair dryer? A clothes iron? A juice extractor? of the previously mentioned 5 devices, 3 of them are exempt, but 2 are not, can you guess which ones are not exempt?

Did you guess correctly? This is where the old adage “the devil is in the details” comes to play. As is the case with much of the FCC rules, they are simply written, but often difficult to interpret. Thankfully the Office of Engineering and Technology (OET) has a Knowledge Base (KDB) system at https://apps.fcc.gov/oetcf/kdb/index.cfm, where one could go and research common questions or ask a question if needed.

One such KDB, answers the question “What household appliances, identified as Part 15 unintentional radiators, are considered exempt from the equipment authorization procedures?”.
On March 29th 2012 the answer was updated by adding to the list of Non-Exempt Devices; Power Tools, Cordless Multi-Tools and Battery Operated Tools . That is to say, those items are not considered appliances with respect to the 15.103 exemption and are subject to FCC testing.
 
Ref;
Publication Number 772105 (3/29/2012) (new)
Publication Number 772105 (11/19/2009) (old)

FCC Amends Rules for Tank Level Probing Radar

The FCC announced on Tuesday that they are expanding the scope of the proceeding proposed to cover Tank Level Probing Radar (TLPR) devices, originally applicable only to devices operating in the 77-81 GHz band, and contained within steel or concrete tanks. Citing requests for waivers and other inquiries as evidence of the increasing demand for a comprehensive set of guidelines for general level probing radar (LPR), to allow the use outdoors and on other frequencies, the FCC is proposing an amendment to Part 15 rules that would apply to the operation of LPR devices installed in both open-air environments and inside storage tanks in the following frequency bands:  5.925-7.250 GHz, 24.05-29.00 GHz, and 75-85 GHz.

Level probing radar applications are diverse but among the popular uses are process control systems used to measure the amount of various substances such as liquids and granulates.

Ref;

FCC 12-34A1

ET Docket Nos. 10-23, 06-216 and 07-96, 25 FCC Rcd 601 (2010). 

Opportunity for innovative cordless broadband use - FCC modifies Part 15

(Photo credit: Wikipedia)

In a report and order released today, the FCC is amending part 15 subpart D covering Unlicensed Personal Communications Service devices (UPCS band). The introduction of the R&O is as follows;

“

By this action, we modify Part 15 of the rules governing the operation of Unlicensed Personal Communications Service (UPCS) devices in the 1920-1930 MHz frequency band (UPCS band) to promote more efficient use of the UPCS band and to facilitate the introduction of a new generation of unlicensed devices capable of supporting broadband connectivity using Digital Enhanced Cordless Telecommunications (DECT) technology. Specifically, we eliminate the least-interfered channel monitoring threshold for UPCS devices and reduce the number of duplex system access channels that a UPCS device must define and monitor from 40 to 20 channels in order to use the least-interfered channel access method.  These changes will provide UPCS devices, particularly those designed to transmit with wider bandwidths, access to more usable channels (i.e., combined time and spectrum windows) than are permitted under the existing rules and unleash innovative cordless broadband technologies in the UPCS band, while limiting the potential for causing interference to other devices.  We also modify the rules to remove outdated provisions and to make other minor updates.

“

ref;

ET Docket No. 10-97

Industry Canada publishes new / updated Radio standards

On January 28th Industry Canada published the following radio standards; (Link to IC web site)

• Radio Standards Specification RSS-111, Issue 4: Broadband Public Safety Equipment Operating in the Band 4940-4990 MHz, which sets out the requirements for certification of radio transmitters and receivers in the band 4940-4990 MHz for public safety applications;

• Radio Standards Specification RSS-182, Issue 5: Maritime Radio Transmitters and Receivers in the Band 156-162.5 MHz, which sets out the requirements for certification of radio transmitters and receivers in the maritime service in the band 156-162.5 MHz; and

• Radio Standards Specification RSS-288, Issue 1: Global Maritime Distress and Safety System (GMDSS), which sets out the requirements for certification of the shipborne radiocommunication equipment that meets the requirements of the GMDSS.

 

In addition Industry Canada announced changes to RSS-Gen and RSS-310 , effective immediately , via notice NOTICE 2012-DRS0126. These changes modify section 2.2 of RSS-Gen covering Receivers, and noted that section 3.1 from RSS-310 is no longer required.

RSS-Gen section ‘ 2.2 Receivers ’ clarifies that ;

“Only radiocommunication receivers operating in stand-alone mode within the band 30 MHz to 960 MHz and scanner receivers are subject to Industry Canada requirements”

and

“All other receivers are excluded from any Industry Canada certification, testing, labeling and reporting requirements.”

Are on-board electric vehicle battery chargers exempt from FCC equipment authorization?

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Under Title 47, Part 15 Subpart B § 15.103, the first item on the list of exempted devices is

“(a) A digital device utilized exclusively in any transportation vehicle including motor vehicles and aircraft.”

The clear answer is “Yes” to the question, “are electric vehicle battery chargers exempt”,… right? … What would you say?

As is the case with much of part 15 subpart B, in order to comply with the intent, you need a little common sense, good familiarity with electromagnetic energy propagation, the ability to think like an FCC engineer, and finally, a Knowledge Database publication (KDB) from the FCC with a clear “yes” or “no” answer to any question you may have, and you may have many.

See Publication Number: 892282

Question:
Is a battery charger and associated digital electronics on-board a vehicle that is used for charging the vehicles battery while parked and connected to AC power lines exempt from an equipment authorization under 15.103.
Answer:
No. Section 15.103, Exclusions, paragraph (a) does not apply to battery chargers for electric vehicles that can be used for charging while stationary and connected to an AC power line. The exemption is only intended for digital devices which operate primarily when the vehicle is operating in a mobile environment such as on a road or highway where the potential for interference is low. When stationary and connected to the AC power line, typically in a residential environment such as a home garage or driveway, the potential for interference by both AC lines conducted and radiated emissions is greater. The battery chargers and associated electronics on board an electric vehicle are therefore subject to an equipment authorization under the verification procedure as a Part 15  Class B or Class A (industrial vehicles) unintentional radiator (switching power supply and digital device).

Digital Transmission Systems and Broadband over Power line among newly published FCC knowledge database (KDB) articles

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The Office of Engineering and technology maintains a knowledge database at https://apps.fcc.gov/kdb . The primary function of this service is to provide the public a means to research answers to equipment authorization questions. For questions that are particularly complex, frequently asked, or often misinterpreted, the FCC provides guidance documents on the subject.

Among the latest of these guidance documents , are guidance for performing measurements on Digital Transmission Systems (DTS), and an answer to the question “What are the measurement guidelines for equipment authorization for BPL systems?”

For Digital Transmission Systems (DTS), the primary changes are;

• A revision and expansion of spectrum analyzer-based measurement methodologies.
• A revision to the procedure for measuring power spectral density.
• An expansion of guidance for measuring unwanted (out-of-band) emissions.
• A new provision to permit antenna port conducted measurement of unwanted emissions in
  restricted bands.

For BPL, or, Broadband over Power line Systems, the FCC points to Second Report and Order FCC 11-160, namely Appendix D of the order, for measurement guidelines on these devices, this includes both in-house BPL and Access BPL. The rules that govern FCC compliance of BPL systems were revised In October of 2011. See my October 2011 article for background and history on this topic.

Ready-Made Connecting devices (cables) under EMC directive?

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During the revision of the EMC directive 89/336/EEC, back in 2003, one of the most controversial proposals was the inclusion of “Ready-made connecting devices” within the scope of the EMC directive.

Ready-made connecting devices would encompass passive product, typically 3rd party in nature, designed to interconnect and be connected to apparatus covered within the scope of the directive, in effect classifying such connecting devices as apparatus themselves within the scope of the directive.

Products such as network cables, Audio / Video cables, and other interconnecting cables and adaptors would come under such classification and be subject to the protection requirements of the EMC directive (to paraphrase; must not interfere with others and must operate in the presence of interference without significant loss of performance) , thus requiring testing and marking as any other apparatus would.

It was argued that the term, “Ready-made connecting devices”, itself was ambiguous and unclear. Eventually it was decided that the devices represented no major interference potential, and because of the costs manufactures would incur for testing and marking, it was removed from the scope of the directive.

With the current revision and alignment of the EMC Directive with New Legislative Framework (NLF), the EMC directive 204/108/EC once again is subject to modification, and potential scope expansion. One such change being circulated for inclusion is that ready-made connecting devices be considered again and brought under the regime of the EMC directive.

In a proposal from the German Administration (BNetza), it is argued that in light of experience gained since 2003, the non interference claims argument cannot be maintained. The proposal claims there is no longer any serious doubt that insufficiently shielded connecting devices greatly increase the interference potential of TV and Cable networks in particular. The proposal cites several reports with data supporting this conclusion. One such report shows a  peak 30dB difference in screening effectiveness between two types tested, from most to least shielding, and notes that cable connectors can contribute around 10 dB of difference. See   ”The Concise Report of the CENELEC/ETSI Joint Working Group on the digital dividend" of 12 August 2010 (section 7.3)

The proposal suggests  that the following requirement be added to the new EMC directive;

Ready-made connecting devices, although incapable of generating electromagnetic disturbance in isolation, may generate or transmit electromagnetic disturbance when connected to an apparatus and should therefore be considered to be apparatus for the purposes of this Directive.

With ready-made connecting devices being defined as;

ready-made connecting devices' intended for connection to an apparatus by an end user for the transmission of signals, which are placed on the market separately from such apparatus, and which are liable to generate or transmit electromagnetic disturbance when connected to it.

This addition would then subject cables and connectors to the same technical requirements as any other product under the EMC directive, regardless of the component’s active or passive nature.

EN 55013 modified and draft going for vote

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EN 55013 is the EMC emissions standard for broadcast receivers and associated equipment. The standard is aligned with the European Union’s EMC directive as published in the official journal. The EMC directive is a CE marking directive, and compliance with this directive is compulsory for most electrical / electronic products prior to placing on the European market.

Previously reported in a post back in the summer of 2009, EN 55013, QP vs RMS, it was noted that the EU commission was holding off publishing reference to the newest edition of EN 55013, 2009, in the Official Journal.

The CENELEC technical committee, CLC/TC 210, had decided that the standard should not be published, without the link to the EMC Directive, and accordingly has set up a task force to seek a resolution.

It was agreed that the new draft common modifications should be circulated under UAP. The current project name is EN 55013:201X

The CLC/TC 210 Secretary proposed that the following explanation appear in the forward to the draft common modifications, furthermore this is not to be included in the final publish standard, should the draft be accepted:

“The text of CISPR/I/296/FDIS, the future CISPR 13 ed 5.0, received a positive vote in CENELEC, but was not ratified due to technical objections raised by the EMC Consultant. These would have prevented the listing of the standard in the Official Journal of the European Union as a harmonised standard providing a presumption of conformity with the protection requirements of the EMC Directive 2004/108/EC. The following draft includes common modifications to address these objections, and they have been agreed by the EMC Consultant and the responsible committee, TC210. It is submitted to UAP.”

It is expected that in light of the upcoming CISPR 32, perhaps appearing within a couple years, that EN 55013 will then be deleted. At that time, the use of the QP detector will have become obsolete and replaced by the RMS/Average detector.

It should be noted that the UK is not in favor of issuing the document under UAP, nor is Italy. The UK proposes to wait and see what happens with CISPR 32. The draft will be submitted under UAP none the less.

The last word on Power Line telecom (PLT) in the EU, EN 55022:2006 applies in full, maybe….

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Power Line communication devices continue to be a controversial subject, with respect to the Electromagnetic Compatibility of such devices. We have been following this subject for both the United States, and for Europe. The latest round comes from across the pond with the rejection (negative vote) of the European Norm targeted to cover the testing of these devices, prEN 50561-1:201X. For background on this topic, see my past article “An update on PLT, Power Line Telecommunications, in Europe”.

Due to the negative vote on prEN 50561-1:201X, and a lack of a specific standard covering the emissions testing for PLT devices, EN 55022:2006 applies in full for these devices as of October 1st. It should be noted that many newer high speed advanced PLT devices cannot pass the requirements of EN 55022:2006 at this time.

This conclusion will be confirmed by a note published in the Official Journal reference to harmonized standards under the EMC directive.

CENELEC may offer a second vote, indicating that the choice is between EN 50561-1 and EN 55022. If this vote fails, no further option exists.

What does this mean for product on the market? Are recalls required for non compliant devices? What about new product placed on the market? The Commission is expected to accept a reasonable Date of Withdrawal (DoW) as proposed by working group 11, and until that date, manufacturers should still be able to continue placing product on the market using the Declaration of Conformity and Notified Body TCF path. The EU market authorities are “encouraged” to accept this.

The group of European Notified Bodies are meeting to discuss, and will consider the Technical Guidance Note (TGN) on the matter, after the meeting. Is this the end of the debate? Time will only tell, and we’ll continue to post when we learn more.

Hearing aid compatibility for wireless handsets

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FCC publishes Second Further Notice of Proposed Rulemaking covering wireless hearing aid compatibility rules for handsets. Interested parties may file comments and reply comments on or before December 1st and December 16th respectively.

FCC seeks comments on conclusion to adopt the new 2011 ANSI standard into the Commission’s rules as applicable technical standard for evaluating hearing aid compatibility of wireless phones. The proposal is to adopt the new standard as “permissible” rather than mandatory, with the intent to ease burdens on manufacturers.

Within the discussion of the proposed rulemaking document, the FCC “tentatively concludes that the adoption of the new technical standard would not raise any major compliance issues or impose materially greater obligations with respect to newly covered frequency bands and air interfaces than those already imposed under Commission rules”.

Under the proposed rules, a manufacturer will be permitted to submit for certification using either the 2007 version, or the 2011 version of the ANSI standard.

Broadband over Power line systems rule amendment

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FCC Part 15 has been amended with new rules covering BPL systems. In July of 2009, a request for further comment was issued (See previous post), this is the conclusion of the commission’s response to the directives of the DC Circuit Court of Appeals remand,  after a challenge by the National Association for Amateur Radio, AKA American Radio Relay League (ARRL).

In this rule change, the commission finds that the information submitted in response to the RFC/FNPRM does not warrant any changes to the emissions standards or the extrapolation factor.  The rules do include some notable changes, among them, modification of the rules to increase the required notch filtering capability for systems operating below 30 MHz from 20 dB to 25 dB, and, establishing a new alternative procedure for determining site-specific extrapolation factors generally as described in the RFC/FNPRM, furthermore, adopting a definition for the “slant-range distance” used in the BPL measurement guidelines to further clarify its application.

Read the full ET Docket No. 03-104, Second Report and Order.

FCC issues a number of updates

A total of 6 guidance documents and 3 drafts for review were posted today on the FCC site, among these updates are procedures for Multi antenna systems (i.e. MIMO) as well as U-NII devices . This list includes the following updates;

Publication Number	Question	Answer
628591	What equipment cannot be certified by a Telecommunications Certification Body?	The attached document 628591 D01 TCB Exclusion List v12r01 identifies equipment that are excluded from being certified by a TCB.
610077	What are the post market surveillance requirements for a Telecommunications Certification Body (TCB)?	Section 2.962(g) of the FCC Rules requires a TCB conduct appropriate post-market surveillance activities in accordance with ISO/IEC Guide 65. The requirements for TCBs were specified in the Commission's Report and Order (R&O) in GEN Docket 98-68 (FCC 98-3...
648474	What are the test procedures for SAR evaluation for handsets that contain multiple transmitters and antennas or wireless charging battery covers?	The attached documents: 648474 D01 SAR Handsets Multi Xmiter and Ant v01r05 provides SAR evaluation considerations for handsets with multiple transmitters and antennas. 648474 D02 SAR Policy Handsets Multi Xmiter Ant v01r01 provides policies for SAR Evaluation….
662911	How are measurements made on a device that employs a single transmitter with multiple outputs in the same band?	The attached document, 662911 D01 Multiple Transmitter Output v01r01 provides guidance for measurements of conducted output emissions of devices that employ a single transmitter with multiple outputs in the same band. The guidance applies to devices that ...
789033	What are the general test procedures for measuring compliance of U-NII devices to Section 15.407 requirements?	The Attachment below - 789033 D01 UNII General Test Procedures v01- provides test procedure guidance for measuring compliance to the general technical requirements of Section 15.407. Note: This test procedure replaces and supersedes guidance contain...
690783	What are guidelines for TCBs for listing SAR numbers on FCC equipment authorization grants?	The attached document -690783 D01 SAR Listings on Grants v01 -provides guidance for Telecommunication Certification Bodies (TCBs) for uniform listings of specific absorption rate (SAR) numbers in the comments field of grants of certification.

In addition, a number of drafts are available for review and comment;

Date Posted:
Oct 25 2011 4:13PM
Last Date to Post Comments:
11/25/2011
View Document:
Comments, Notes, and Conditions Listed on OET Equipment Authorization Certification Grants

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Date Posted:
Oct 25 2011 9:25AM
Last Date to Post Comments:
11/25/2011
View Document:
Confidentiality

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Date Posted:
Oct 25 2011 9:10AM
Last Date to Post Comments:
11/25/2011
View Document:
Permit But Ask procedure & Permit But Ask List

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Date Posted:
Oct 3 2011 9:52AM
Last Date to Post Comments:
11/04/2011
View Document:
Guidance for Performing Compliance Measurements on Digital Transmission Systems (DTS) Operating Under 15.247
There have been 3 comments made on this document:

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EMC list of harmonized standards update, new ITE standards

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The list of standards for use under the EMC directive, 2004/108/EC, published in the Official Journal of the European Union has been updated.

Among the updates within the list are the inclusions of the 6th edition of the emissions, and 2nd edition of the immunity standards, for Information Technology Equipment (ITE), titled EN55022:2010 and EN55024:2010. These official titles are the modified version of CISPR 22:2008, and unmodified CISPR 24:2010.

The inclusion in the official journal is a prerequisite for a standard to be considered harmonized for use in the presumption of conformity with the essential requirements of a given directive. This allows these new standards to be used for compliance testing.

These new versions will supersede their predecessors on December 1st 2013, at which time they become mandatory. Any new product shipped into the European Union on or after December 1, 2013, must comply with the new ITE specifications.

You can find a copy of this list at Compatible Electronics’ European Conformity Assessment page, or at the the EC Enterprise and Industry web site when available.

 

By: J Klinger

FCC publishes new draft testing guidelines for U-NII devices

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Public comment is now open, until September 23, 2011, on the FCC guidelines for testing Unlicensed National Information Infrastructure (U-NII) devices, in accordance with CFR 47 Part 15, Subpart E.

In addition to the measurement standards called out in section 15.31, and ANSI C63.10, these guidelines will form the general test procedures for testing all U-NII devices for compliance with the technical requirements of section 15.407.

The U-NII radio band is an unlicensed band divided into three spectrum segments in the 5GHz range, 5.15–5.35 GHz, 5.47–5.725 GHz and 5.725–5.825 GHz. U-NII devices use wideband digital modulation techniques, and provide a wide array of high data rate mobile and fixed communications for individuals, businesses, and institutions. Examples are 802.11a devices.

Dynamic Frequency Selection (DFS) functions, which are required between 5.25 – 5.35 GHz and between 5.47 – 5.725 GHz for the protection of government radar systems, are covered in a separate document. See FCC Order, ET Docket No.03-122 (FCC 06-96).

For devices that transmit on multiple outputs simultaneously such as MIMO and beam forming technologies, FCC KDB Publication Number 662911 also applies.

The new guidance replaces Public Notice DA 02-2138 of 8/30/02 and contains the following changes;

• The document interprets and clarifies the language of 15.407(a)(4) (maximum conducted output power)
• Revises the spectrum analyzer-based methodologies for measuring maximum conducted power and provides an option to use an RF power meter
• Revises the methodologies for measuring Peak Power Spectral Density (PPSD) to match those used to measure maximum conducted output power
• Specifies the use of max hold when measuring Emission Bandwidth (EBW)
• Defines compliance with 15.407(a)(6) (peak excursion) in terms of the ratio of maximum of the peak-hold spectrum to the maximum of the average spectrum—eliminating the need to compute the ratio at each frequency (a process that had resulted in unintended failures near band edges)
• Adds guidance for measuring unwanted emissions.  The guidance interprets the non-restricted band limit as a peak limit and restricted band limits as including both average and peak limits.  Both restricted and non-restricted band limits are based on continuous transmission with no subsequent reduction for operational duty cycle.  The guidelines permit both restricted and non-restricted band compliance be demonstrated by radiated measurements or by antenna-port conducted measurements combined with radiated cabinet emission measurements.

By: J Klinger

Antenna Calibration Procedure

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The office of Engineering and Technology, Laboratory Division, released a public draft review regarding proper antenna calibration procedure.
The document answers the question;

“What procedure should be used to calibrate antennas used to make radiated emission measurements and normalized site attenuation (NSA) measurements”?

According to the public draft review, the revised ANSI standard, ANSI C63.5-2006 provides the proper procedure and is based on a horizontally polarized measurement performed on a standard antenna calibration site at a 10 meter distance.
Antenna factors collected in this manner can then be used for vertical or horizontal measurements at distances of 3 meters or more.
OET DRAFT FOR REVIEW