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).
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.
Didn’t really follow it too closely. Key result seemed to be -118 dBm for 90% Pd and -123 dBM for wireless microphone.
Sometime ago, I mentioned I didn’t really know what was going on in E3 (End-to-End Efficiency), but today Eric Nicollet gave a briefing.
Goal: Introduce cognitive wireless systems into the beyond 3G world. Does indeed build directly on E2R and follows up. December 2009. Total budget 18.6 million euros (11 million from EU).
- Identify Means to increase efficiency of system managemenet and operations
- Develop path for gradual non-disruptive evolution of wireless networks
- Make an initial design
Really keying on cognitive pilot channel (I’ll have something up on that maybe next week). They dedicated a maybe 3 minutes out of 15 just to CPC with everything else programmatic.
Main use cases: dynamic spectrum access and allocation, distributed RRM, self organizaing networks
I was always disappointed with E2R because it seemed to focus on developing a systems-of-systems model without actually defining / developing the algorithms that would run in the systems. Hopefully, this will change in E3.
The following came up during today’s SDR Forum General Meeting downselected to those things which were new / news to me.
SCORED (Software and COgnitive Radio for European Defense)
An overview is given in this presentation (pdf). Appears to combine Thales, INDRA, SELEX, and Ericsson with a primary focus on SDR with the hopes of adapting the SCA for use for European applications. CR architecture appears to be building on E2R architecture. It started in 2007.
NTIA DSA Coordination Group – generally keeps NTIA informed of DSA technology developments (can’t find a link, but it is mentioned on this site which means half of CRT knew of it even if the other half didn’t)
Peter Tenhula noted the # of short some spectrum lease arrangements were actually down in the most recent quarter (27 as opposed to 32). Spectrum Bridge may have entered the market too early, but then again it might pick up during the 700 MHz build-out.
26 FCC IDs for SDR have now been granted (as of June 2008). Of interest, new ones were granted to Aruba and Trango using DFS for ISM / UNII bands presumably on WiFi devices.
Some unspecified government cognitive radio R&D project in Japan is supposed to start up (and specify details?!?) in July 2008. A similar situation is apparently occuring in Korea. If I hear something more concrete, I’ll post links.