Google's Larry Page Calls FCC White Space Test 'Rigged'

By Thomas Claburn


In an address to Washington lawmakers on Wednesday to advocate opening of a portion of the television spectrum for Internet networking, Google co-founder Larry Page charged that a recent FCC "white space" device test had been rigged to fail.

Page, according to The Washington Post account of his remarks, said, "The test was rigged deliberately. That's the kind of thing we've been up against here, and I find it despicable."

The test Page referred to was conducted in August by the FCC's Office of Engineering and Technology. Its purpose was to determine whether a prototype device for transmitting Internet traffic over the unused white space in the TV spectrum could sense the presence of wireless microphone signals.

Google along with Dell, HP, Microsoft, Motorola, and others have been lobbying the FCC to authorize this use of the TV spectrum. They believe it could be used to connect underserved communities to the Internet at a low cost, to open the door for innovative new services, and to promote the development of an underused resource.

TV broadcasters, telecom companies, and wireless microphone companies are among those that oppose the idea, fearing disruption of their use of the spectrum, not to mention competition from a new form of Internet service.

On Aug. 19, following the FCC test, the White Spaces Coalition sent a letter to the FCC that echoed Page's claims. The letter charged that during the FedEx Field test, wireless microphone operators were broadcasting wireless microphone signals on multiple channels used by TV broadcasts.

Beyond being a violation of FCC rules, this buried the wireless microphone signals inside more powerful TV signals and assured that the Philips white space device being tested failed to detect wireless microphone signals.

Mark Brunner, senior director of public and industry relations at Shure, which makes wireless microphones, refuted Page's charges in an e-mailed statement.

"The FCC's wireless microphone field tests were carefully planned and thoroughly executed based on sound engineering science and real-world operating scenarios," he said. "These tests were open to the public, and those who choose to discount the results -- which have not yet been published -- had every option to be present and to witness them for themselves."

Call to Action: White Spaces

On November 4th, the FCC plans to change the rules that govern the use of wireless microphones and other wireless audio equipment. The new rules may make it impossible for you to continue using wireless microphones as you do today, and your entire inventory of wireless equipment may become obsolete within months.

The current deadline to send comments to the FCC on this issue is Monday, October 27th. It is critical that you act immediately to tell the FCC and your legislators that these changes are unacceptable to you.

Background

The FCC is reorganizing the UHF television band, coinciding with the transition from analog to digital television broadcasting. Soon, TV stations will occupy a smaller section of the UHF spectrum because digital stations can be spaced more closely together - even on adjacent channels - without interfering with each other. There will still be unoccupied channels in every market – referred to as “White Spaces” – just as there are now.

Why does this matter to you? These "White Spaces" are used by wireless microphones and instrument systems, in-ear monitors, and production intercom systems. Beginning on February 18, 2009, the FCC plans to allow consumer wireless devices – mobile phones, BlackBerry™’s, etc. – to access the internet using the same frequencies currently used by wireless audio equipment.

These devices can cause catastrophic interference if operated on the same frequency as wireless audio devices. The effect on a wireless microphone could be decreased range (perhaps to as little as 10 feet), an increase in the number and severity of audio dropouts, or even complete interruption of the signal. Tests have also proven that White Space devices can interfere with DTV reception and even cable TV signals.

Two Channels Are Not Enough

Shure has proposed that the FCC set aside eight ‘protected’ TV channels (2 in the VHF band and 6 in the UHF band) in each market, in which unlicensed wireless microphones could operate without interference from White Space devices. The devices would check an online database and avoid transmitting on the channels that are ‘protected’. The problem: the FCC plans to set aside only TWO TV channels for unlicensed wireless mics – and they won’t reveal where they are in the spectrum. Two TV channels (12 MHz of spectrum) would only be enough for four to ten wireless microphones – less if other wireless mic users are nearby. This is insufficient for many users.

Tests Say “No”, But The FCC Says “Go”

For wireless microphones operating outside of the two ‘protected’ channels, the FCC proposes to use a technology known as “spectrum sensing.” This would require White Space devices to detect DTV stations and wireless audio equipment and avoid transmitting on the frequencies that they are using. The FCC’s own tests have demonstrated that this technology often fails to detect that a wireless microphone is present, even at very short distances. The problem: the FCC plans to allow new devices that rely on spectrum sensing anyway.

No Clear Plan For Large-Scale Users

In situations where many wireless audio devices are in use, several open TV channels may be required. The FCC has proposed that users would need to register in an online database that would include the event location and duration. The problem: the FCC has not revealed who would have access to this database. Many types of wireless users could be locked out.


The FCC Needs to Hear From You

The FCC needs to hear from wireless users, installers, and resellers that sufficient protection for wireless microphones is essential. Contact the FCC and your Congressional representatives directly, using one of the links below. Tell them how important wireless audio equipment is to your organization’s activities. If you are a performer or producer, tell them how it will affect your performance or content. If you are an installer or reseller, tell them how this will impact your business.

NARAS

The National Academy of Recording Arts and Sciences

Click here to go to the NARAS Advocacy page, which allows you to find your U.S. Representatives and Senators by entering your zip code.

NAMM

The National Association of

Music Merchants

Click here to send a letter to the FCC specifically stating the interests of the music equipment industry.

INFOCOMM

The Audiovisual (AV) Association

To express your support for Infocomm’s letter to the FCC representing the interests of AV equipment dealers and installers, go to www.infocomm.org

Shure Incorporated

Click here for instructions on how to file a comment with the FCC, and a direct link to the FCC’s Electronic Comment Filing System.

Spectrum Reallocation & White Space An Explanation and Current Developments

October 21, 2008

Many questions have surfaced in recent weeks over the actions of the Federal Communications Commission (FCC) regarding digital television, spectrum re-allocation, and wireless microphone technology. These actions have an impact on the current professional wireless microphones. The following information is published in order to reduce misunderstanding about these issues.

How is the TV spectrum being reallocated? The U.S. is in transition from conventional analog TV to digital TV. This is scheduled to be completed on February 17, 2009. At this same time, the reassignment of TV channels 52-69 (698 – 806 MHz) will be completed. This band will partially be used for emergency communications in channels 63, 64, 68, and 69. The rights to use the majority of the remaining channels were auctioned to AT&T, Verizon, and Qualcomm to provide what is being termed as advanced wireless services (AWS). This raised billions of dollars for the federal government and was therefore called the digital dividend. This will affect wireless microphones operating between 698-806 MHz (generically called the 700 MHz band), such as our evolution wireless C range systems.

Is this the White Space issue I’ve been hearing about? No. The White Space debate is separate and distinct from the digital dividend.

Will my C range evolution wireless system operate after February 2009? Technically systems will still work. However, wireless mics will be prohibited to operate between 698 –806 MHz in the near future. This restriction could go into effect as early as February 17, 2009. It is likely the FCC will make an announcement after their meeting scheduled on November 4th, 2008.

What is the White Space debate? The FCC is considering to allow a new class of unlicensed consumer electronic products, known as white space devices (WSD), to operate in locally unused UHF TV channels 21-51. If enacted, these new devices would also affect wireless mic users.

The debate centers on how current licensed devices (wireless mics are considered to be licensed devices by the FCC) will be protected from these new unlicensed white space devices (WSD). The FCC has acknowledged the need to prevent interference from white space devices to digital television signals and wireless microphones. The FCC recently conducted tests on WSD prototypes and published a report in mid October. A link to this report is referenced below. Once again, we expect further FCC action after their meeting on November 4th.

What has Sennheiser been doing regarding the White Space debate? Sennheiser has been directly communicating with the FCC and legislators making them aware that the term “white space” is a misnomer since broadcasters, film producers, and professional entertainers have been using licensed devices, such as wireless microphones and monitoring systems, in this spectrum for years. Therefore major news, political, sports and entertainment events would not be able to operate reliably if the spectrum was randomly flooded by new unlicensed devices. To demonstrate this point, Sennheiser participated in the FCC field tests of WSD prototypes.

Sennheiser has also been deeply involved in helping to shape response to the FCC through the Professional Audio Manufacturers Association, the Sports Video Group, and the Microphone Interests Coalition.

What about the future? It is certain that the amount of spectrum available for wireless microphone use is shrinking. The 700MHz range will no longer be available for use for wireless mics. The remaining usable UHF spectrum may become smaller, or it may be shared with new devices. No matter what happens, Sennheiser will continue to support wireless microphone use with the most flexible products and service available.

Sennheiser is continually developing unique ways to face new challenges with the same reliability that has always characterized our products.

Explanation of Recent FCC Activity There have been two recent communications from the FCC that have caused heightened anxiety: Notice of Proposed Rule Making banning wireless mics from the 700 MHz band This NPRM can be read in its entirety at:
http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-08-188A1.pdf
http://hraunfoss.fcc.gov/edocs_public/attachmatch/DOC-284758A1.pdf

Sennheiser had predicted this action. That's why we advised our customers back in early 2007 that the FCC was likely to impose restrictions on operating wireless mics between 698 MHz and 806 MHz. We therefore eliminated systems operating in this range from our regular assortment and made them available only based on a special order.

Sennheiser submitted a detailed response to this proposal on Oct 3rd and again on Monday, Oct. 20th.

We are lobbying hard for a measured migration out of the 700 MHz band that includes a grace period that would allow existing users to continue to operate in this band on a non-interference basis. The full comment to the FCC is posted on the following webpage: www.sennheiserusa.com/spectrumreallocation The White Space Technical Report The FCC executive summary can be found at: http://hraunfoss.fcc.gov/edocs_public/attachmatch/DA-08-2243A2.pdf

This report relates to spectrum sensing capabilities of proposed white space devices (WSD). Other than the FCC stating that "...we believe... the ‘proof of concept’ has been met," there is nothing new in this report.

1) WSD devices would still be required to detect and avoid wireless mics
2) Fixed WSD are being considered ahead of the more problematic portable units
3) More development is required on WSDs to meet the performance standards that have been set Furthermore, there is also a proposal being considered that would dedicate at least two TV channels in every market for wireless microphone use. Major events, such as sports, would have additional channels reserved.

The bottom line is this: wireless mics will continue to be used throughout our nation. The FCC has scheduled a discussion and may vote on these issues on November 4th. We will distribute the results of this vote as well as a detailed analysis of what this means to wireless mic users. In the meantime, feel free to contact me with further questions. Thank you.

Joe Ciaudelli
860-434-9190 Ext. 508
SENNHEISER ELECTRONIC CORP

Equalizing Lapel Mics

By Marty McCann

Question from: Ian Stott of Architectural Audio Singapore

"What EQ Settings/curve would you recommend for a lavaliere mic in a difficult environment such as a reverberant church or hall!"

I would recommend a Cardioid pattern lapel mic, even though the pattern is altered when placed on the chest. Some put the mic too far down on their chest. The user should drop their chin to their chest and put the mic directly below that point. The farther down from this point results in even more mid-range chest cavity resonance that colors the sound. This chest cavity resonance and the gain before feedback is a constant battle with lapels (Wireless or hard-wired).

Too often the church customer (who is often rather technically challenged in the first place), tries to resolve the EQ'ing of the lapel mic with the overall main system EQ. This of course is a mistake, because of how it will adversely affect the overall systems performance, i.e., normal vocal microphones and instruments taken direct are negatively affected by the hacking away of the main equalizer in order to chase away frequencies that are problems for the wireless Lav mic only. A dedicated EQ (inserted into the wireless Mic's channel) is the only way to begin to even get any kind of a handle on this application. Even then due to the drastic amount of Mid-range cut necessary to get intelligibility out of the lapel Mic system (this is before feedback suppression), there is often not enough cut remaining in this region for further control of feedback.

Over the years, I have addressed this problem in high visibility, high $'s installations by either using a parametric along with a 1/3 octave to tweak the system, or more recently (since we no longer manufacturer a parametric), I specify ½ of a 2/3 Octave EQ and a 1/3 Octave EQ to process the lapel Mic's channel.

Now here is where the problem is further complicated. In many installations, the lapel Mic is used by more than one individual (sometimes several). Due to the individual nature or timbre of peoples speaking voices, along with the fundamental resonance's of each voice (that is determined both by the vocal chords and the size of the chest cavity), one size does NOT, fit all. The pastor or CEO doesn't understand this at all. At times when it can be determined that certain designated people will be using the lapel system, I have specified 2 (yes 2) CEQ-280a programmable Equalizers, with stored setting for various presenters or speakers.

Now down to the EQ process. Too often the less experienced system integrator or operator will just ring out the mic for feed back. This results in less than desirable tone and intelligibility. EQ for intelligibility first then go for feedback suppression (once again you probably need more than 1 EQ to accomplish both effectively). On the average the required mid-range notch is centered somewhere from 315 to 630 Hz (this is the individual variable) depending on the person speaking. This notch can be two to three octaves wide at the -3dB down points (depending on the lapel mic and user). Because of the small Electret diaphragm and its proximity to the users mouth, there is often more energy above say 8 kHz than is necessary. A variable high cut is a good tool here (that's why I prefer the EQ-31FX over the Q-31FX, the variable low cut is also handy here). Some people's voices exhibit a strong sibilance in the annunciation of Ssss sounds. This of course is mainly at 6.3 kHz on a 1/3 Octave EQ.

When the budget won't allow for two equalizers, one technique is to first start with all of the EQ sliders at the top (this is not a good idea with some cheaper filter designs due to the ripple or poor summing of the filters), then to EQ for tone, followed by appropriate cuts for feedback suppression. With some cheap EQ's this technique would also result in a poor S/N ratio.

While on this subject, we have had tremendous results with the performance of our new PVM-2 wireless headset mic. Because of it's positioning away from the chest and close to the mouth, it needs VERY LITTLE EQ, and can often suffice on the channel strip EQ on a decent mixer. The problem is a lot of people think they look like a Dork with the headset on. In my case, I have overcome the dorky feeling because the end result is soooo much better performance.

Also, some theater productions tape the lapel Mic over the actor's ear or into their hairline (using flesh colored surgical tape). This works well with some of today's smaller Mic elements, such as the PVM-1 Lavaliere microphone.

©2009 Peavey Electronics. Used by permission All rights reserved. Terms/Privacy
__________________________________________

David McLain | The Wireless Guy! | CCI SOLUTIONS
Be seen. Be heard.
PO Box 481 / 1247 85th Ave SE
Olympia, WA 98507-0481
Voice: 800/426-8664 x255 / Fax: 800/399-8273

email: dmclain@ccisolutions.com
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RF Spectrum Reallocation Information Bulletin

From SennheiserUSA:
Wireless microphones primarily operate on frequencies in the UHF TV spectrum. 

Changes in technology and national policy will affect wireless microphone operation in the future. Click here for a summary of the current status. 

The United States is in the midst of a transition from traditional analogue television broadcast to digital TV (DTV). Currently, networks are broadcasting both analogue and digital signals on separate channels simultaneously. It is planned that by February 17, 2009 the analogue channels will be turned off freeing up the channels they are currently occupying. At that time, the Federal Communications Commission (FCC) will reallocate channels 52-69 (698 – 806 MHz) for new services such as public safety communications and auction to the private sector. This is termed the "digital dividend". 

In addition, the FCC is considering proposals to allow unlicensed wireless devices to operate in channels 2-51 that are not occupied by local TV stations. These include broadband services, PDA's, cell phones, home networking devices and other consumer electronics. These unoccupied local TV channels are being called "white spaces". If such legislation is enacted, these devices will be new potential sources of interference for wireless microphones, intercoms, and monitoring systems. 

The proposed date to allow unlicensed devices to use the spectrum is also February 17, 2009. However, in an effort to bring broadband to underserved areas quicker, Massachusetts Senator John Kerry has introduced the Wireless Innovation Act of 2007 (S. 234) that would shorten the timeline to within 180 days of enactment. A version of this bill has also been introduced in the House of Representatives (H.R. 1597) by Representative Jay Inslee of Washington. 

Separately, New Hampshire Senator John Sununu has introduced the White Spaces Act of 2007 (S. 337). It would open white spaces within 90 days of passage, or by October 1, whichever comes first. This bill also considers the option of auctioning licenses for the spectrum. 

Conversely, Congressman Bobby Rush of Illinois has introduced The Interference Protection for Existing Television Band Devices Act of 2007 (H.R. 1320). It would require manufacturers of unlicensed devices to demonstrate that their product will not interfere with existing devices, such as wireless mics and monitoring systems. It also calls to cease deployment of fixed wireless devices, such as broadband services to rural areas, until after the digital television changeover is complete. The bill suggests that new portable devices would be allowed to use white spaces after fixed devices have been operating for three years without causing interference. 

The FCC and industry leaders have stated that adequate time must be allowed to develop solutions that will permit unlicensed devices to operate without causing harmful interference to current users of the TV spectrum, including wireless microphones. 
  • There are some proposed solutions and compromises to allow co-existence. These include:Listen Before Talk
  • This proposed technique relies on the unlicensed devices to check for existing RF-traffic before transmitting.
  • Geolocation/Database
  • Location sensing and consultation with a database of broadcast license assignments (use of GPS receiver). It would require entering requests for frequency/spectrum reservation into the 'consulted' database by any potential user.
  • Local Beacon
  • Reception of a locally transmitted signal that identifies which TV channels may be used in the local area for unlicensed use. It would require entry of used frequencies/spectrum to be entered into (and removed from) the data stream to be transmitted by the beacon.
Each of these solutions has merit. White space legislation and these proposed solutions are likely to be subjected to long debate and go through several revisions before any bill is enacted. We will continue to keep you posted on any major developments. 

In the meantime, feel free to contact us or visit our web site for the latest guidance on frequency selection in your area. Thank you. 

For more information, contact:
Joe Ciaudelli
Sennheiser Electronic Corporation
1 Enterprise Drive
Old Lyme, CT 06371
Phone: (860) 434-9190