09.03.08
Posted in White Space at 10:29 am by jody
I’m coming to the conclusion that white spaces will ultimately be licensed. Sure, it’s a late entrant solution, but consider the following from different parties’ perspectives.
1: FCC (ultimately the only opinion that matters)
Their dual missions (more or less) is to increase public utility from spectrum and to maximize revenues for the government . If white spaces are licensed, they will get used (which increases efficiency over current usage, though likely less than unlicensed) and the government should make a bit of money (not easily done with unlicened devices). Further, licensing should provide better mechanisms for addressing interference (via punishment and after-the-fact management ala Nextel) than if the public has it (see Marines + garage door opener); plus these mechanisms would be ones the FCC is used to.
2: Service providers
Selling services over licensed spectrum is a model they know well, so they’ll be quite comfortable with it. Assuming fixed site equipment (ala 802.22), the networks should look a lot like femtocell networks which the service providers should be comfortable with. Now there will clearly be more spectrum in rural environments than urban environments, but rural broadband that’s the rationale for 802.22 and the ostensible rationale for the White Space Alliance.
3: Equipment vendors
They would still get to sell equipment, but now to customers with a clear business model. Plus any equipment sold would be more likely to conform to 802.22 which is virtually complete now, which means they’ll get to start making sales sooner than a yet to be defined standard for “WiFi on steroids”.
4. White space opponents (broadcasters / wireless mic users)
I think a key argument for them against unlicensed use was: “Who do we sue?”. With licensed service provisions, it should be readily apparent who is responsible for interference in different areas and they’ll have deep enough pockets (the service providers) to make it worth while to go after them (which then gives the service providers incentive to not interfere).
5. White space coalition (Google, Microsoft)
Except for perhaps Adaptrum, most of the White space coalition (or alliance or whatever they want to be called these days) are primarily interested in increasing available data bandwidth. They’ll get it with licensing. Motorola and Phillips should still be more than happy by the opportunity to sell femtocell-like white space equipment in a licensed environment.
6. End users
They’ll still get more data than if white space use is disallowed (though perhaps less than unlicensed), plus there will be an easier mechanism to provide for more than just hot-spot coverage (via the service provider infrastructure), which means more coverage than unlicensed.
Thoughts on licensed white spaces
- This would make 802.22 a winning technology as it provides an immediate mechanism for implementing licensed white space access. Heretofore, I thought it might be DoA.
- This should open up a transition to a mobile 802.22 standard.
- Would still be good to not specify exactly what standard (or family of standards) has to be used in the spectrum to allow for usage to evolve.
- Explicit permissions for resale, leasing and subdivision of licenses would be good.
- I would still like to see some additional unlicensed spectrum opened up to let smaller markets bloom.
- It would still be a significant step forward for cognitive radio, just a smaller one.
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08.26.08
Posted in Quick Links, Shameless self-promotion, White Space, artificial intelligence at 10:43 pm by jody
(link) Shared Spectrum, and Mark McHenry in particular, gets a nice writeup in the WaPo. The politics of unlicensed white space also comes up.
(link) IET Workshop on SDR and Cognitive Radio. It’s in London on the 18th, so I won’t be there. But Keith from CTVR will be. *UPDATE* In the comments, Keith notes that some of the presentations may appear as webcasts at this site.
(link, pdf) On Monday, Oct 27 E3 and the SDR Forum will host a joint workshop on business, exploitation modem architecture, regulation and standardization aspects of SDR and CR. I’m tentatively slotted to give an outbrief on the SDR Forum’s contribution to an ITU report on “Cognitive radio systems in the land mobile service.” (lots of interesting stuff to cover in 30 minutes)
(link) Cognitive radio got some love at the Intel Developers’ Forum. I don’t see the talk in the catalog though.
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08.20.08
Posted in TV Bands, White Space at 10:16 am by jody
Google has started a propaganda promotional campaign to get public opinion behind opening up the TV Band’s white spaces for unlicensed devices. The website is here where you can sign a petition urging the FCC to open make unassigned TV bands officially unlicensed, if you’re so inclined (I’m not yet at this moment).
According to Fierce Wireless
Google is hoping public pressure will help it in its campaign to get the FCC to make white space spectrum available for unlicensed wireless Internet devices. The company today launched a campaign called “Free the Airwaves” that will target rural and Native American communities across the country that have inconsistent or no Internet connections.
Google has been lobbying to get this spectrum, which sits between the airwaves currently licensed to TV broadcasters, to be used to develop new mobile communications devices. However, the initiative has raised the ire of the National Association of Broadcasters, which argues that white-space devices may interfere with existing television broadcasts.
Since broadband over TV bands is already authorized for rural spaces, but for fixed devices (802.22), this will likely be counter-productive as the ostensible reason has already been (or is being) addressed via a less contentious route.
This is the latest example where I like Google and in general agree with their direction, but fear that they’re hurting the white space cause by 1) being way too combative, 2) not having a solid technical grasp of what they’re proposing, 3) showing really bad timing (last week’s news on wireless mic detection was not countered, so I’m assuming it was relatively accurate).
Since they’re making their positions so very public and stridently before all of the technical issues are worked out (and I think they will be, primarily via geolocation and transmitter registries ala 802.11y), I fear cognitive radio and white spaces will be tarnished thus making later deployment of cognitive radio into other bands and the deployment of new applications more difficult.
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08.11.08
Posted in Conferences, Quick Links, White Space, research initiatives at 10:36 am by jody
First, contrasting viewpoints on white space testing:
(link) From Shure (after the Redskins / BIlls test):
“The FCC’s tests of prototype white space devices at FedEx field prior to Saturday’s game between the Redskins and the Bills conclusively show that spectrum sensing white space devices will cause harmful interference to wireless microphones during live events. Simply stated, the prototype devices were unable to consistently identify operating wireless microphones or distinguish occupied from unoccupied TV channels. More troubling, the devices failed to detect the presence of wireless microphones when switched on - an occurrence that takes place multiple times during any NFL game.
(link) From Motorola:
In an interview yesterday with FierceWireless, Steve Sharkey, Motorola’s senior director, regulatory and spectrum policy, said that the FCC has just finished most of the outdoor white space device testing and that Motorola’s white space device did very well in the tests. Sharkey said that Motorola uses geolocation technology, which means it uses a combination of location technology (such as GPS) and a database that advises the device on what channel to use and whether or not there is compatibility with other white space devices.”The geolocation approach has proved highly reliable,” Sharkey says.
(link) And Verizon wants white space devices licensed:
“Generally we have favored licensed spectrum,” Tauke said at a press conference, “but we are continuing to look at what the potential may be here.” On the other hand, he said he wanted to be certain that these applications, currently being evaluated by the FCC, don’t interfere with Verizon wireless products or anything else. “Nobody has passed the test” just yet, Tauke said.
My two cents. Applying these sorts of political slants to what should be a purely technical assessment (I have no first hand knowledge of the testing and no particular dog in the fight, but it seems to me they can’t all be right on the assessment) is inherent to decisions related to public goods and is a reason (among many) why I wish we would start transitioning to a regulatory regime that more closely mimicked private property.
(link) Effectively the same Motorola story as above, but this link has a line I want to discuss further.
Sharkey calls the tech “absolute, solid protection,” which should make members of the white space coalition happy — though we haven’t heard positive word from Philips, Adaptrum and InfoComm yet, who were also testing devices alongside Motorola, but aren’t using the geolocation technology. That, and the FCC has the final word on all of this, so we’ll just have to wait for that word from on high before we start riotous, interference free partying in the streets
The emphasis was in the original. There was a paper submitted to DySPAN that I wanted accepted (though not a very good paper and not anyone’s I know so ’twas rejected) which unwittingly made what I think is an important point - if 1) a primary user is turning off and on at unpredefined times and 2) is not helping secondary users (via a beacon or via any other method), then 3) secondary users will have to detect the presence of the primary when it starts transmitting. This then means that you simply can’t have assurances of interference-free operation if you want the secondary system to have any sort of useful throughput.
In practice, this means if we are constrained to detecting wireless mics via detection methods only, we will not be able to guarantee interference-free operation.
On a related note, I think IEEE USA did a real disservice to cognitive radio with their advocacy as it sets up the technology to fail by suggesting an impractical condition is inherent to the concept of cognitive radio.
By definition, CRs should be inherently non-interfering on a completely independent basis.
(link) Keith has done a valuable service and posted site measurements as matlab files on the DySPAN conference site for any researcher to use (mmm… real data). Unfortunately the DySPAN site appears to be down at the moment, so do check back later on this link. *Update* Here’s a direct link (zip).
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08.05.08
Posted in Conferences, Quick Links at 10:17 am by jody
Got an email stating that ISABEL08 is unofficially open for submissions until Aug 10. (I can’t go, it conflicts with the SDR Forum)
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07.28.08
Posted in Conferences at 7:23 pm by jody
Since it still says that paper acceptance should occur today on the DySPAN website, I thought it would be a public service to pass along a note I got from Milind Buddhikot (technical co-chair) today.
“We plan to send out ACCEPT notifications on August 8 and request final photo-camera ready papers to be submitted to IEEE by August 21.”
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07.25.08
Posted in Conferences, Quick Links, White Space at 4:48 pm by jody
(link) The International Symposium on Wireless and Pervasive Computing has issued a call for papers. Related topics include cognitive radio and cooperative communications. It’ll be held from Feb 11-13, 2009 in Melbourne, Australia. Papers are due October 12.
(link) The schedule for the next SDRF meeting / workshop is now posted. The focus of the workshop is “Government and Industry R&D Agendas for Next Generation Radio Technologies” (read as cognitive radio) and Bill Lehr (MIT) will give a talk on “Building the Ecosystem for Commercial Cognitive Radio”. Interestingly, the agenda page (pdf) lists meeting times for a white space task group. (Other than an agreement that it would be a good idea, it hasn’t actually gotten off the ground yet.)
(link) White Space Tests at the DNC and RNC conventions?
(link) The WaPo has a nice article (from yesterday) overviewing the current round of testing. Interestingly, only the Motorola device is aided by geolocation - something I expect to eventually be a requirement. (The WaPo sometimes requires a login, if you’re asked for one, try these.)
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07.23.08
Posted in Uncategorized at 9:05 am by jody
Or hey, why doesn’t my link to post x work anymore?
Short version: Upgraded to wordpress 2.6. Old permalinks to posts with a date format are broken, everything else should be fine (links are there, just a different format for the url).
Long version: Noticed that yahoo (the host) wasn’t automatically upgrading wordpress as they were supposed to and there was some weird stuff showing up in search engine crawls (background). So I used the wordpress widget to automatically upgrade the site and virtually everything broke. After a bunch of manual php and sql editing, I think everything is back to its quasi-normal state, except for the permalinks whose format I had to change. The permalinks will appear normal if you’re clicking through from this site, but old external links will be broken because of the format change.
(This is apparently not an uncommon problem, nor one I could find a fix for. So if you know of a fix for permalinks and yahoo hosted wordpress 2.6, leave a comment. FYI, as a “feature” yahoo eats the .htaccess file whose editing wordpress suggests for other hosts.)
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07.18.08
Posted in Quick Links, TV Bands, White Space, military, regulation, research initiatives at 3:41 pm by jody
Or all white space, all the time! But first, some non-white space links…
(link) Call for more dynamic spectrum policies. Not a lot new there for those active in the policy arena. Key graphs:
“Traditionally, spectrum policy has been all about exclusive licensing for specific service, during extended time periods. The considered opinion now is that static long-term licensing of spectrum hinders fast innovation cycles, and across the board. The fact of the matter is that new technologies tend to diffuse faster than regulations, especially in dynamic sectors like telecom. Already, the considerable strides made in digital technology, such as spread spectrum, software defined radio and mesh networks, do call into question the policy of administrative allocation of exclusive-use licenses.
…
With novel software, coordination amongst service providers in real time can allow umpteen secondary devices to transmit even while providing the right quality of service and non-interference for cellular customers. The bottom line is that we need proactive spectrum policy to fastforward growth of the most desired applications, as they evolve and take off.”
(link) The US Air Force is funding Finnish cognitive radio research. (I don’t know which Finns. I assume CWC @ Oulu, but I don’t see confirmation on their research page)
Officials from the Air Force, Army and Navy are now funding a Finnish research program that explores new approaches for improving telecommunications network management.
The ultimate goal is to build on this basic research and create a cognitive network that will use rational decision-making methods to improve the speed and quality of information delivered via Defense Department networks.
(link) Ars Technica has a nice overview on the current round of white space testing.
(link - pdf) The current white space test schedule. Note a sports and entertainment venues are on the schedule.
(link) There was a complaint filed with the FCC on interference from unlicensed wireless microphones. Mmmm politics. I thought I went into engineering to avoid that. (FYI, the Public Interest Spectrum Coalition is not completely new as the article implies; they also were active in the 700 MHz block - see link1 & link 2)
A group calling itself the Public Interest Spectrum Coalition (PISC) and the Media Access Project have filed a complaint with the FCC regarding the unlicensed use of wireless microphones. The Media Access Project has filed a proposed “pathway to authorisation” for existing users that would help to protect new public safety and commercial wireless services operating on UHF channels 52-60 from 17 February 2009.
Michael Marcus has much more on this.
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07.10.08
Posted in Quick Links, Uncategorized, White Space at 11:04 am by jody
Since, procrastinating on starting my paper reviews = blogging, here’s some random white space links / news:
KU issued a press release on their white space testbed here. I didn’t see anything technically useful in the press release which just says the testbed shows that white space devices will not interfere with DTV reception, but there’s no details on the setup. Poking around the KU website, I did find this white paper (pdf) from May 2007, which has some measurement data from that testbed to backup a claim that adjacent channels could be used. But that seems a bit dated.
(link) Sports stadiums have offered their facilities for live testing of white space devices this fall.
(no link - first-hand reporting!) It looks like the SDR Forum (SDRF) will be spinning up a project to develop an analytic model for mobile white space devices. There’s supposed to be an initial phone call in late July to organize the project and based on other discussions, I believe this activity will be run out of the SDRF cognitive radio working group (CRWG) beginning in August.
If it is indeed hosted out of the CRWG, we’re pretty liberal about accepting contributions from non-SDRF members, so even if you’re not in the SDRF, you can participate (though bylaws say you can’t vote nor could you hold a leadership position).
I’ll post more information about this after the late July phone call.
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