Steven J. Crowley, P.E.
Consulting Engineer
Recently
Experimental Radio Applications at the FCC
This summarizes a selection of applications for the Experimental Radio Service received by the FCC during February 2011. These are related to cognitive radio, land mobile, TV white space, unmanned aircraft systems, satellite terminals, ultra-wideband, wildlife tracking, interference detection, and radar. The descriptions are sorted by frequency.
Stanford-developed Transceiver Operates Full Duplex on a Single Channel, Reduces Network Bottlenecks
To avoid interference, wireless transceivers can switch between transmit and receive on one frequency (Time Division Duplex (TDD)). Or, they can transmit and receive at the same time on different frequencies (Frequency Division Duplex (FDD)). There’s been a flurry of press reports about a new radio system, developed by Stanford researchers, that can operate full duplex on a single channel; that is, transmitting and receiving at the same time on the same frequency, something not done before.
NTIA looks at Contraband Cell Phones in Prisons
Contraband cell phones are sometimes used by prisoners to talk to a child after school, for Facebook updates, or to post videos to YouTube. Other times they’re used to plan strikes, organize escapes, and order executions. Prisoner-directed crimes will occur with or without wireless, but cell phone access reduces barriers to them, and it’s a growing problem.
Experimental Radio Applications at the FCC
This summarizes a selection of applications for the Experimental Radio Service received by the FCC during December 2010. These are related to FM broadcasting, Positive Train Control, TV white space, mobile satellite terminals, GSM, UMTS, through-the-wall surveillance radar, troposcatter communications, millimeter-wave propagation, flight test telemetry, Doppler weather radar, and air-to-air military radar.
ITU Loosens Hold on Term “4G” – Now Calls it “Undefined”
The debate won’t end but the volume is dropping on the what-is-4G controversy. Previously, I’ve written about the ITU’s characterization of 4G as only applying to the two radio technologies it has designated as IMT-Advanced: LTE-Advanced and WirelessMAN-Advanced (the latest version of WiMAX).
“Trusted” Academia Favored over Industry in FCC’s Proposed Experimental Rules
With praise for academia, the FCC has adopted a Notice of Proposed Rulemaking (NPRM) that would make it easier for colleges, universities, and non-profit labs to conduct radio experiments. The proposed rules create a “program experimental radio license” that lets those institutions apply for broad, long-term, blanket licenses that reduce the need to go to the FCC for each and every experiment. Licensees would instead give seven days’ notice of new operations to the FCC and to the public via an FCC website. Potential interference victims could object before or after the experiment starts, but the burden of proof is on them. Licensees would agree to keep interfering signals on their property. Find something interesting during the experiment that makes you want to try a new frequency? Submit a new notice. It’s a streamlined process that will reduce licensing delays and speed up academic R&D. To get this efficiency, however, interference policing shifts from the FCC to potential interference victims; they’ll have to be on heightened alert.
FCC Takes Further Steps toward Mobile Broadband in TV Spectrum
On November 30, the FCC adopted a Notice of Proposed Rulemaking (NPRM) as a preliminary step toward making the current TV broadcast spectrum available for use by fixed and mobile wireless broadband services. The proposed rules would do three things: 1) make fixed and mobile wireless services co-primary with broadcasting in the FCC’s Table of Frequency Allocations, 2) create a regulatory structure giving two or more TV stations the option to share one 6 MHz channel, and 3) improve VHF TV reception through power increases and adoption of receiver antenna standards. No service rules are being proposed; they’re to come later. Congress has yet to approve incentive auction authority.
ITU Gets “4G” Pushback from IEEE 802
The IEEE 802 Executive Committee today approved correspondence asking ITU for clarification on its use of the term “4G” in an October 21 press release on IMT-Advanced. The main concern is ITU’s characterization of IMT-Advanced as “true 4G.” IEEE 802 observes that some in industry and government use 4G to mean mobile broadband technologies other than IMT-Advanced. Consequently, IEEE 802 says, ITU’s announcement has caused such users to be on the receiving end of “public response” (i.e., negative publicity), and could cause “significant disruption” to existing technical activities and documentation. It also observes that such use of 4G seems inconsistent with ITU-R Working Party 5D’s prior consideration of the term.
The FCC’s Spectrum Deficit Estimate
The FCC’s National Broadband Plan (NBP) recommends that the Commission make available 500 MHz of new spectrum for wireless broadband, including 300 MHz for mobile use. In support of that recommendation, on October 21, the FCC released an FCC Omnibus Broadband Initiative technical paper: Mobile Broadband: The Benefits of Additional Spectrum. The paper concludes that mobile data demand is likely to exceed capacity in the near term and, in particular, that the spectrum deficit is likely to approach 300 MHz by 2014.
Experimental Radio Applications at the FCC
This summarizes a selection of applications for the Experimental Radio Service received by the FCC during October 2010. These are related to ultra-wideband, machine-to-machine, satellite, GSM, white space, and radar.
What do I mean by “selection?” I look at all applications for new experimental license or special temporary authority (ignoring renewals, modifications of existing licenses, and transfers of control). From those, I pick the ones I find most interesting, which is most except for the following:
- GPS repeaters, such as those put in a factory to replicate a GPS environment for testing. (Note, however, that companies regularly get tripped up by not demonstrating compliance with separate NTIA requirements.)
- Short-term authority for video program production. Someone needs a video link to cover a golf tournament or football game, perhaps by using flight-test telemetry bands (with that coordinator’s permission) for a day.
- Demonstrations for customers. Demonstrations at trade shows.
- An application very similar to one covered recently.
- Applications too vague or lacking enough detail to write much about. If applications are very lacking, FCC staff will sometimes ask for more information.
- Electromagnetic compatibility (EMC) compliance testing including RF immunity testing for compliance with European regulations.
- RF integration testing. (A radar from company A is paired with telemetry from company B and installed on a ship from company C.)
- Applications for general-purpose antenna test ranges.
- Applications for which confidentiality treatment has been sought. Companies can do this under the FCC’s rules, but I suspect it’s overdone at times. The request for confidentiality is made public, and may have some details. (A couple of times I have seen companies put what I think is the confidential information in the confidentiality request.) That, and a bit of independent research, can give me an idea what they’re up to. If I can make an educated guess, I will, saying so.
On to October’s applications:
- Zimmerman Associates filed an application (with supporting exhibits) for special temporary authority to test the capability of using a full polarimetric UWB radar system for identifying roadside bombs and improvised explosive devices (IEDs). Testing is to be on 3100-5600 MHz at Fort A.P. Hill, Virginia. The prototype equipment uses time-modulated ultra-wideband (UWB) technology developed by Time Domain Corporation. It generates a signal that is position modulated; the position of the modulated pulse varies randomly in time so as to produce a spectrum that approximates Gaussian noise.
Mobile Patent Lawsuits and Patent Pools
Techdirt prefers the following view of mobile patent lawsuits over one prepared by Information is Beautiful a few weeks earlier. Take these graphics with a grain of salt; both versions, for example, show Nokia versus Qualcomm, but those two have settled (for now). In its version, Techdirt adds entities that aren’t vendors, such as patent holding firms (in the hexagons).
Other entities get pulled in, too. Show up at an industry standards-setting meeting in which a plaintiff or defendant is participating, and you might get a subpoena, just for good measure.
Patent pools are sometimes used for efficiency, including that gained from reduced litigation. Techdirt makes an argument against them saying they restrict innovation. It prefers to let the market decide, presumably by having patent holders negotiate with each other. It has a point, but that is what wireless companies did before patent pools, and the pools’ formation were themselves a market response to that hassle. I don’t think the IEEE 802.11 patent pool has hindered the remarkable innovation still ongoing in that family of technologies. To the extent it has, I think it would be offset by patent pool efficiencies, such as moving things along more quickly. If companies don’t like a pool, they can and do choose to not join and instead negotiate separately. Qualcomm and some other companies, for example, chose to sit out the patent pool for 3G W-CDMA, even though they held essential patents.
