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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Wireless and Communications => Topic started by: Jason Glass on July 26, 2017, 11:09:00 PM
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Here's a heads-up about an experimental license that was recently granted. If you have gigs coming up in Pittsburgh or Santa Clara, you might want to bring a spectrum analyzer.
PUBLIC NOTICE
FEDERAL COMMUNICATIONS COMMISSION
455 12TH STREET, S.W.
WASHINGTON, D.C. 20554
News media information 202/418-0500
Released:
July 26, 2017
Report No. 492
EXPERIMENTAL ACTIONS
The Commission, by its Office of Engineering and Technology, Experimental Licensing Branch, granted the
following experimental applications during the period from
5/1/17 to 5/31/17:
<EXCERPT>
CARNEGIE MELLON UNIVERSITY WI2XXL 0226-EX-CN-2017
New experimental to operate in 174.00 - 698.00 MHz to test TV White Spaces.
Fixed & Mobile: Carnegie Mellon University Main Campus & Vicinity, Pittsburg (Allegheney),
PA; Mountain View (Santa Clara), CA
For details about the experiments, see:
https://apps.fcc.gov/els/GetAtt.html?id=189789&x=. (https://apps.fcc.gov/els/GetAtt.html?id=189789&x=.)
https://apps.fcc.gov/els/GetAtt.html?id=190784&x=. (https://apps.fcc.gov/els/GetAtt.html?id=190784&x=.)
Part 74 Licensees, this is your contact to shut them down if they step on your registered freqs:
"CMU's stop buzzer point of contact for this application is: Craig Hesling, Tel. 843-422-5405 - email - [email protected]"
This is publicly available information published by the FCC here: https://apps.fcc.gov/els/GetAtt.html?id=191992&x (https://apps.fcc.gov/els/GetAtt.html?id=191992&x)
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Quick aside question: why is a university licensing white space systems?
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Quick aside question: why is a university licensing white space systems?
What they say: CMU proposes to conduct research to demonstrate the potential of wireless “white spaces” networks in order to investigate and develop improved wireless applications and services
What they mean: They're investigating a whole new way to make white spaces unusable for wireless mics.
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BTW, although the info is fairly clear and concise by FCC standards, here are some details that hopefully don't slip past us:
Although they explain that operation will be on and around campus, they requested and got authorization for 20km radii.
They are licensed to operate 200 non type certified portable devices and 20 fixed devices within those radii, and the fixed devices TX in excess of 2.4W.
Sent from my Nexus 5 using Tapatalk
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Quick aside question: why is a university licensing white space systems?
Universties utilizing White Space is hardly groundbreaking.
The University of West Virginia was a pilot program for campus network backhaul over White Space technology back in July 2013 through an organization/initiative called Air.U. But WVU White Space usage in Morgantown, WV is something very different than CMU usage in Pittsburg, PA.
http://wvutoday-archive.wvu.edu/n/2013/07/09/nation-s-first-campus-super-wi-fi-network-launches-at-west-virginia-university.html
http://www.techrepublic.com/article/white-space-broadband-10-communities-doing-big-projects/
http://www.airu.net
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Part 74 Licensees, this is your contact to shut them down if they step on your registered freqs:
"CMU's stop buzzer point of contact for this application is: Craig Hesling, Tel. 843-422-5405 - email - [email protected]"
This is publicly available information published by the FCC here: https://apps.fcc.gov/els/GetAtt.html?id=191992&x (https://apps.fcc.gov/els/GetAtt.html?id=191992&x)
I'm curious how this works and I'm hoping to get a little education about whitespace devices in urban areas. The Santa Clara zipcode 94043 and a quick search on Spectrum Bridge lists the following information:
TV Freq Availability
24 530-536 Reserved **
26 542-548 Reserved **
5 76-82 Available **
11 198-204 Available **
20 506-512 Available **
23 524-530 Available **
22 518-524 White Space **
What kind of wattage can a white space device transmit at?
I happen to have a part 74 license and have a protected entity registered about 10 miles from that location. Is there something else I should be aware of? I've never encountered a whitespace device in the wild...
Also is there a way I can see all protected entity registrations in a given area?
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Lisa,
There are fixed and portable white space devices. Fixed ERP is up to 4 watts on channels 2-51. The fixed devices cannot operate next to an active TV channel. Portable devices use channels 21-51. Their erp is 100mw, 40mw if operating next to an active TV channel. From what I understand they can access the FCC database (I'm not sure how often) and 'should' be able to sense wireless microphones.
I'm curious how this works and I'm hoping to get a little education about whitespace devices in urban areas. The Santa Clara zipcode 94043 and a quick search on Spectrum Bridge lists the following information:
TV Freq Availability
24 530-536 Reserved **
26 542-548 Reserved **
5 76-82 Available **
11 198-204 Available **
20 506-512 Available **
23 524-530 Available **
22 518-524 White Space **
What kind of wattage can a white space device transmit at?
I happen to have a part 74 license and have a protected entity registered about 10 miles from that location. Is there something else I should be aware of? I've never encountered a whitespace device in the wild...
Also is there a way I can see all protected entity registrations in a given area?
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Lisa,
There are fixed and portable white space devices. Fixed ERP is up to 4 watts on channels 2-51. The fixed devices cannot operate next to an active TV channel. Portable devices use channels 21-51. Their erp is 100mw, 40mw if operating next to an active TV channel. From what I understand they can access the FCC database (I'm not sure how often) and 'should' be able to sense wireless microphones.
Thanks Dan for the information. I'm not too concerned about anything under a watt but 4 watts could be trouble. What constitutes "next to an active TV channel"? When I do an FCC TV query for that location with a radius of 100 kilometers, there are active TV stations next to (or on) all the white space TV channels.
Here's a link to my query results:
LINK (https://transition.fcc.gov/fcc-bin/tvq?call=&arn=&state=&city=&chan=0.0&cha2=69&serv=&type=&facid=&asrn=&list=1&dist=100&dlat2=38&mlat2=0&slat2=31&NS=N&dlon2=122&mlon2=6&slon2=59&EW=W&size=9&NextTab=Results+to+Next+Page%2FTab)
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The closest scan I have to Santa Clara is San Jose. It shows channels 20->26 are not occupied. Ch 16 and 17 are public safety which means ch 14 could be used by a white space device. I would have to look into how many db above the noise floor is considered active. Maybe Henry or Jason will chime in.
Does someone have a spectral signature of a white space device they can post? I assume they use either 8VSB or QAM modulation.
Thanks Dan for the information. I'm not too concerned about anything under a watt but 4 watts could be trouble. What constitutes "next to an active TV channel"? When I do an FCC TV query for that location with a radius of 100 kilometers, there are active TV stations next to (or on) all the white space TV channels.
Here's a link to my query results:
LINK (https://transition.fcc.gov/fcc-bin/tvq?call=&arn=&state=&city=&chan=0.0&cha2=69&serv=&type=&facid=&asrn=&list=1&dist=100&dlat2=38&mlat2=0&slat2=31&NS=N&dlon2=122&mlon2=6&slon2=59&EW=W&size=9&NextTab=Results+to+Next+Page%2FTab)
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The closest scan I have to Santa Clara is San Jose.
I had assumed that white space devices (TVBD's), including the one's applied for above, had to access the database to determine the TV channel whitespace it could operate in, not local scans. Is this not the case?
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I had assumed that white space devices (TVBD's), including the one's applied for above, had to access the database to determine the TV channel whitespace it could operate in, not local scans. Is this not the case?
No. These WSD's are operating under an experimental STA (Special Temporary Authority) and do not have to be FCC technical rules compliant. They must however cease operation immediatley if an incumbent licensee experiences interference, hence the reason for the "stop buzzer" person's contact information.
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Does someone have a spectral signature of a white space device they can post? I assume they use either 8VSB or QAM modulation.
Looks similar to COFDM.
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I think I may know what Carnegie Mellon is up to in Pittsburgh, and I'm not sure that it would interfere all that much with what we do at this point. Someone from CMU is going to install an 'experimental' system to assist path of egress for the visually impaired. From my understanding this is app based on either andriod or ios.
There is a convention for the visually impaired coming to a property I work with (Hotel AV) and they are installing the system so that the visually impaired know where to walk their seeing eye dogs (like to the field in which dogs 'walk'). From what I was told, the last time the convention was in they used some kind of buzzer outsize that buzzed 24/7 and another guest got so agitated he ripped it down and threw it over the hill side. Before my time.
A friend of mine worked on a similar project for the Disney parks involving guided tours, talking Mickey dolls, and strategically placed RFID tags. Get close enough to the RFID and Mickey tells you something about the ride or whatever - this was 10-12 years ago. No idea what happened with the project.
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I think I may know what Carnegie Mellon is up to in Pittsburgh, and I'm not sure that it would interfere all that much with what we do at this point. Someone from CMU is going to install an 'experimental' system to assist path of egress for the visually impaired. From my understanding this is app based on either andriod or ios.
It would have to be a custom made personal device: There currently is no iOS or Android device on the market with a white space (TV band frequencies) chip set.