NTIA Spectrum Sharing Testbed Draft Phase I Rules

Posted in NTIA, spectrum sharing testbed, white space at 5:56 pm by JamesNeel

The government side of white space spectrum got up and running yesterday with the NTIA issuing a request for comment on their phase I (equipment characterization) draft test plan.

The notice is here (pdf) and the draft test plan is here (pdf).

From what I understand the test-bed participants (Adapt4, Adaptrum, BAE, Motorola, SSC, VT) previously commented and this is more generally open. However, comments are currently due by Dec 30, 2008 which would be a problem for most groups. I think that’ll get pushed back.

An overview of the NTIA testbed effort is here.


Cognitive Radio Activities at SDRF / JSTeF San Diego Jan 09 Meeting

Posted in conferences, CRWG - cognitive radio work group, shameless self-promotion, white space test group at 12:58 pm by JamesNeel

The agenda for the next SDR Forum meeting has been posted. It’s in San Diego from January 26-30 and will be co-hosted with the JTRS Science and Technology Forum.

The following cognitive radio related activities will go on:

CRWG Meeting

The Cognitive Radio Work Group will be meeting primarily to continue putting together an extensive survey document on quantifiable benefits of cognitive radio for later use in ITU submissions and position papers as well as general evangelization on cognitive radio

White Space Test Group

The White Space Test Group will be meeting primarily to work on use case documents for input to the 802 ECSG on white spaces and for later SDRF development of test specifications for white space devices.

Meta-language for Mobility Work Group

I’m not certain what the MLM group will be doing as they just finished up a use case document (where can meta-languages help supprot cognitive radio). They generally coordinate with 1900.5 and may be working on specifications. (Oddly, I only have so many hours in the day and can’t participate in everything)

Public Safety SIG

While dealing with more general public safety comm / SDR issues, at least some of their meeting time will likely be used to work on their cognitive radio use case document (intended to help identify required technologies / insertion points).

Cognitive Radio JTRS SBIR Briefings

Shared Spectrum and CRT (us) will each give 20-minute briefings on our JTRS-sponsored Phase I SBIRs on cognitive spectrum management.

I’m not certain what they’ll speak on, but I figure it’ll be on policy and DSA. Their open abstract is here.

We’ll talk about distributed non-collaborative spectrum optimization / management of MANETs and what we did in Phase I (our open abstract is here). Besides the big benefits for managing an integrated network, we think our little algorithm suite will be particularly useful for coexistence of white-space devices running incompatible waveforms, so we might touch on that some too.


SDRF White Space Testing Group Starts

Posted in cognitive standards, white space, white space test group at 7:30 pm by JamesNeel

While I’m mentioning cognitive radio groups starting up, the SDRF White Space Testing Group had its first official meeting a couple weeks ago (unofficial meetings had been going on since mid-summer). Right now it’s focused on developing / documenting use cases for white space (beyond “WiFi on Steroids”). This is primarily intended to help develop testing recommendations for white space devices, but will also probably feed into the 802 ECSG on white space mentioned below, which will also be starting with use cases.

The press release announcement is here.

802 study group (ECSG) on white space

Posted in cognitive standards, white space at 1:53 pm by JamesNeel

This is last minute, but I just found out.

There’s a 802 study group on white spaces starting up today. The first telecon/ webex is at 1:00 PM Eastern today (Dec 2). More information (where you can also sign up for the listserv) is here.

There will be telecons every two weeks.


Quick Links 11/19/08

Posted in business, cognitive pilot channel, collaborative research, TV Bands, white space at 12:06 pm by JamesNeel

(link) NAB to push Congress to overturn FCC white space ruling (I’m 99.9% certain it won’t be overturned, but it may impact the non-geolocation-enabled devices).

A statement by NAB suggests that the group may be considering asking Congress to either reverse or substantially alter the FCC’s white-space decision. According to NAB, a large number of lawmakers “publicly expressed opposition or concern over the FCC’s proposed white-space action.”

Among the more notable names listed by NAB are House Commerce Committee Chairman John Dingell (D-Mich.), House Ways and Means Committee Chairman Charlie Rangel (D-N.Y.), Sen. Hillary Clinton (D-N.Y.), Sen. Pete Domenici (R-N.M.), and Sen. Chuck Hagel (R-Neb.).

“There was and continues to be immense concern from a large bipartisan group of lawmakers,” Wharton said, “who recognize the important role that free television broadcasting plays in the daily lives of all Americans. Whether it is for emergency information, AMBER Alerts or news and entertainment, free TV is a service used more than eight hours per day by more than 100 million American households.”

(link) A podcast on who will build the white space network. As opposed to, say, DSRC, I don’t think this is as much of a problem for WISP service. Maybe for other use-cases.

(link) However, Clark Howard (more of a personal finance guy, so that’s how broad white space is now) touts white space for free Internet. If that’s the business model, then there will be deployment issues (see muni WiFi).

(link) Clearwire may use white spaces for added capacity. Since that was news to me, here’s a key excerpt:

The vote was passed 5-0 and will allow Google and friends – including Time Warner, Comcast, and Intel – to pour their $3.2bn into the venture and take 22 per cent of the company. That leaves Clearwire shareholders with 27 per cent and Sprint Nextel with a controlling 51 per cent ownership.

But even that infusion of cash isn’t going to be enough to build the 140 million points of presence New Clearwire is expected to need for national coverage. That’s going to set the company back another $2.5bn at least – possibly a lot more, which explains the sudden interest in white space spectrum.

“I think that presents some interesting opportunities for us, and we’ll be looking at how we might leverage it in the rural areas,” said CEO Benjamin Wolff, in a conference call following the filing of Clearwire’s Q3 results, as reported by Information Week. This fits in well with how Motorola sees white-space spectrum being used: medium-distance fixed connections for telco backhaul, rather than the “Wi-Fi on steroids” that some have been promoting.

(link) Making money coming and going (from both the air interface in the preceding and the content via ads), Google said of the expected boost in internet usage by 25-30%. I think that’s a bit high in the near term, but here’s the nut graph.:

Page predicted the free use of white space will boost Internet use so much, his firm’s online ad revenue will rise 20% to 30% a year.

(link) Dell to include white space capabilities in their laptops.

And for more general cognitive radio…

(link) PicoChip looking at cognitive radio for femtocells. It’s not called as such, but:

picoChip Designs Ltd (Bath, England) has released three reference designs for femtocells that deals with one of the major problems and concerns surrounding the emerging technology.The software designs are said to provide the first integrated ‘network listen’ (or ’sniffer’) capabilities for femtocells.

“A femtocell needs to control itself and fit in with its network environment and ensure there is no interference. This diagnostics capability is hugely important for cell planning, synchronization and handover within networks, and these designs provide the algorithms needed for the necessary measurement and reporting information,”, Rupert Baines, VP of marketing at picoChip told EE Times Europe.

The ‘network listen’ functionality also enables the implementation of the self-organizing network (SON) techniques that will underlay the operation of future networks, and can be used to support timing and synchronization.

Baines notes that currently, most of this diagnostics and interference management is supplied by the femtocell OEMs, often using proprietary algorithms and computational techniques.

(link) A brief overview of the E2R effort.


Unlicensed White Space Approved (Update)

Posted in white space at 11:30 am by JamesNeel

Buried in yesterday’s election returns is a press release noting that the FCC has approved the use of white space devices.

Fcc press release (pdf)

Reuters / Yahoo summary

While I can’t find the actual report and order (FCC 08-260) here’s what I found from the commissioners’ comments and the FCC press release:

  • Required detection technique is geolocation (via database access) + sensing
  • Will consider lower power detection only devices
  • Gelocation database includes registered wireless mic locations (e.g. sporting venues and Broadway)
  • Sensing includes requirement to detect both TV and wireless mics
  • Operating in channels adjacent to TV broadcasts are allowed if transmit powers < 40 mW
  • Higher power levels (??) allowed for nonadjacent channels
  • Unlicensed only
  • Higher power rural transmissions to be addressed later
  • No statement of legal resposibilities of unlicensed interferers

I’ll check again later to see if FCC 08-260 is posted and update this post as needed.


Here’s FCC 08-260: (pdf). Excerpting from the executive summary:

  • We are providing for both fixed and personal/portable devices to operate in the TV white spaces on an unlicensed basis.
  • All devices, except personal/portable devices operating in client mode, must include a geolocation capability and provisions to access over the Internet a database of protected radio services and the locations and channels that may be used by the unlicensed devices at each location. The unlicensed devices must first access the database to obtain a list of the permitted channels before operating.
  • The database will be established and administered by a third party, or parties, to be selected through a public notice process to solicit interested parties.
  • Fixed devices may operate on any channel between 2 and 51, except channels 3, 4 and 37, and subject to a number of other conditions such as a restriction against co-channel operation or operation adjacent TV channels pending consideration of further information that may be submitted into the record in this proceeding. Fixed devices may operate at up to 4 Watts EIRP (effective isotropic radiated power).
  • Personal portable devices may operate on any unoccupied channel between 21 and 51, except channel 37. Personal portable devices may operate at up to 100 milliwatts of power, except that operation on adjacent channels will be limited to 40 milliwatts
  • Fixed and personal/portable devices must also have a capability to sense TV broadcasting and wireless microphone signals as a further means to minimize potential interference. However, for TV broadcasting the database will be the controlling mechanism.
  • Wireless microphones will be protected in a variety of ways. The locations where wireless microphones are used, such as entertainment venues and for sporting events, can be registered in the database and will be protected as for other services. In addition, channels from 2 – 20 will be restricted to fixed devices, and we anticipate that many of these channels will remain available for wireless microphones that operate on an itinerant basis. In addition, in 13 major markets where certain channels between 14 and 20 are used for land mobile operations, we will leave 2 channels between 21 and 51 free of new unlicensed devices and therefore available for wireless microphones. Finally, as noted above, we have required that devices also include the ability to listen to the airwaves to sense wireless microphones as an additional measure of protection for these devices.
  • Devices must adhere to certain rules to further mitigate the potential interference and to help remedy potential interference should it occur. For example, all fixed devices must register their locations in the database. In addition, fixed devices must transmit identifying information to make it easier to identify them if they are found to interfere. Furthermore, fixed and personal/portable devices operating independently must provide identifying information to the TV bands database. All devices must include adaptable power control so that they use the minimum power necessary to accomplish communications.
  • · All white space devices are subject to equipment certification by the FCC Laboratory. The Laboratory will request samples of the devices for testing to ensure that they meet all the pertinent requirements.
  • We will permit applications for certification of devices that do not include the geolocation and database access capabilities, and instead rely on spectrum sensing to avoid causing harmful interference, subject to a much more rigorous set of tests by our Laboratory in a process that will be open to the public. These tests will include both laboratory and field tests to fully ensure that such devices meet a “Proof of Performance” standard that they will not cause harmful interference. Under this procedure the Commission will issue a Public Notice seeking comment on the application, as well as test procedures and methodologies. The
  • Commission will also issue a Public Notice seeking comment on its recommendations. The decision to grant such an application will then be made at the Commission level.
  • The Commission will act promptly to remove any equipment found to be causing harmful interference from the market and will require the responsible parties to take appropriate actions to remedy any interference that may occur.


Open CR positions at CTVR (Ireland)

Posted in Jobs at 10:58 am by JamesNeel

CTVR is running a google ad for PhD students and post-docs that links back to this page.


Google Mapping Spectrum Measurements

Posted in collaborative research, measurements, spectrum at 1:56 pm by JamesNeel

Keith just pointed out to me that he’s posted a google map of their earlier spectrum campaign.

Going all web 2.0 for a moment, what I think would be really cool for the CR community is if we could put together a collaborative spectrum sensing google map so all of the varying measurement campaigns could be synthesized together into one usable super database.


Quantifying the Benefits of Cognitive Radio

Posted in CRWG - cognitive radio work group at 10:55 am by JamesNeel

Yesterday, the SDR Forum Cognitive Radio Work Group agreed to proceed on our next project – survey the open literature to collect the reported quantifiable benefits of cognitive radio into a single white paper.

We’ll be reviewing papers from cognitive radio conferences, e.g., SDR Forum, DySPAN, CrownCom, workshops – e.g., the Microsoft workshop, the handful of cognitiveradiotextbooks, patents, and selected dissertations to identify algorithms and applications that have quantifiable benefits. For example, my SDRF 07 paper reports a distributed/uncoordinated cognitive RRM algorithm that produces a 16x gain in network capacity for unlicensed systems and Mark McHenry’s survey on spectral availabiltiy that reported that on average 10% of allocated spectrum was actually in use (though this varied significantly by band) implying that the application of DSA has an upper bound of a 10x gain in spectrum access.

We’re currently planning on organizing the results into a white paper broken down by targeted application area (e.g., spectrum management, interoperability) and by layer (e.g., cognitive routing). We think it’ll be useful for anyone getting up to speed on cognitive radio (e.g., those asking “why cognitive radio”), useful for regulators (e.g., we’re planning on using this white paper to update the SDRF ITU response on cognitive radio in May 09), and a useful reference for any cognitive radio researcher.

Since this is such a large undertaking, we’ll take help wherever we can get it. So if you would like to help out with this effort, here’s two ways you could help:

  • Leave a comment to this post that a) gives the citation information for a publication you think is relevant, b) describes the reported benefit, c) gives the application area. We’ll still have to read it ourselves and put the description in a format that flows with the rest of the white paper, but this will ensure we don’t miss the publication.
  • Note: if it’s not in the open literature, we don’t want it.

  • If your comment doesn’t appear immediately, don’t resubmit it. WordPress has a serious spam problem so I have to manually approve comments and I may not get around to reviewing comments until the end of the day. (There’s real work to do!)

  • Actively participate in the project. We have telecons alternate Wednesdays at 11:00 AM Eastern.
  • You (don’t have to be an SDRF member to participate in the project, but membership is required for voting purposes (e.g., when we move the document out of the group).

  • If you are interested and have time to contribute, email me (james DOT neel AT crtwireless DOT com).


Final SDRF and DySPAN Programs Technical Programs online

Posted in conferences, shameless self-promotion at 5:50 pm by JamesNeel

(link) DySPAN Program (pdf)

(link) SDRF Program (pdf) (This link may be better for an “at-a-glance” sort of view, though it’s not as complete)


CrownCom 09 Call for Papers

Posted in conferences at 3:16 pm by JamesNeel

(link) CrownCom09 has a call for papers up. It’s a big enough CR conference that I don’t think I have to sell it, so the key information (follow the link for more info):

Conference Site: Hannover, Germany, June 22-24, 2009

Key Dates:

  • Paper Submission Due: 23rd February 2009
  • Tutorial Proposals Due: 23rd February 2009
  • Special Session Proposals Due: 3rd November 2008
  • Acceptance Notification: 20th April 2009
  • Final Papers Due: 4th May 2009


Quick Links 9/17/08

Posted in overview, public safety, quick links, white space at 6:32 am by JamesNeel

(link) iTNews (Aussie mag) interviewed Dr Bostian of VT about cognitive radio. Microsoft is also mentioned.

(link) SlashDot also notes the article, where as always, the comments are the most interesting part (particularly if you want a public perspective), e.g.,

“Cognitive radios!?? Oh no you don’t! (Starts adding layers to tin foil hat.)”

(link) The National Cable & Telecommunications Association issued a letter on white space noting potential interference at head ends. They are not arguing against unlicensed white space devices, but would like the following provisions:

  1. Restrict the operation of portable devices to a maximum of 10 mW and prohibit transmissions in the VHF channels given the high probability of direct pickup interference to TV receivers.
  2. Prohibit operations, at a minimum, on channels 2- 4.
  3. Restrict the operation of fixed devices to at least 400 feet from the external walls of residential buildings.
  4. Prohibit operation of fixed devices in VHF channels.
  5. Require spectrum coordination before operation of portable devices on channels adjacent to those being received at headends.

They add:

Of the suggested methods by which fixed and portable devices might automatically determine channel availability, it appears that auto-location (GPS or equivalent), combined with regular access to a reliable database containing geographically-indexed lists of available channels, has the potential to provide the flexibility and reliability required to protect headend reception.


Quick Links (9/13/08)

Posted in conferences, Jobs, quick links, shameless self-promotion at 10:07 am by JamesNeel

(link) CSIRO PhD position on Cognitive Radio in Multi-hop Wireless Networks

(link) AccessNets (Oct 15-19, Las Vegas) will have a panel session on the “Successes of Dynamic Spectrum Management”

(link) The Communication Networks and Services Research Conference has issues a call for papers. Topics include cognitve radio, software radio, ad-hoc networks, Details

  • Dec 5: Submission deadline
  • Feb 9: Acceptance Date
  • May 11-13 Moncton, New Brunswick Conference

(link) Overview of VT’s historical research efforts. Jeff and cognitive radio gets discussed some.


Block D Auction Update

Posted in public safety, spectrum at 7:52 am by JamesNeel

According to the WaPo, new rules for Block D have been issued:

Under the new proposal, the network would be auctioned as one national block of radio spectrum or, alternatively, as 58 separate regional airwaves licenses. The agency said that it prefers to sell the spectrum as a whole and that it would give priority to such a bid. But if no one meets the minimum reserve price for the national block, the commission would close the auction with a minimum of half of the 58 regional licenses sold.

To attract bidders in a new auction, Martin said yesterday that the minimum price to bid on the network would drop by nearly half, to $750 million. The deadline to build the network would extend to 15 years from 10 years, and any lease charges from public safety officials would be capped at $5 million a year.


Licensed White Space

Posted in white space at 10:29 am by JamesNeel

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.


Quick Links 8/26/8 [Updated]

Posted in artificial intelligence, quick links, shameless self-promotion, white space at 10:43 pm by JamesNeel

(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.


Google: The Kid that Gets Your Side in Trouble

Posted in TV Bands, white space at 10:16 am by JamesNeel

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.


Quick Links 08/11/08

Posted in conferences, quick links, research initiatives, white space at 10:36 am by JamesNeel

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).


ISABEL08 still unofficially open for submissions

Posted in conferences, quick links at 10:17 am by JamesNeel

Got an email stating that ISABEL08 is unofficially open for submissions until Aug 10. (I can’t go, it conflicts with the SDR Forum)


DySPAN acceptance date pushed back

Posted in conferences at 7:23 pm by JamesNeel

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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