Archive for the ‘Spectrum’ Category

Reports from NAB and CTIA Address Efficient Use of Spectrum

Saturday, May 14th, 2011

Recent contributions to the mobile broadband spectrum debate are reports from NAB and CTIA. I envisioned a “dueling reports” piece, but they mostly complement each other. Below I walk through the main points, adding some of my own views.


Experimental Radio Applications at the FCC

Wednesday, April 13th, 2011

This summarizes a selection of applications for the Experimental Radio Service received by the FCC during March 2011. These are related to VHF propagation, satellite communications, TV white space, military communications, radar, software defined radio, aircraft broadband services, adaptive networks, peer-to-peer networks, intermodulation testing, unmanned aircraft systems, maritime broadband communications, border surveillance, target acquisition, and millimeter wave propagation.  The applications are sorted by frequency.


Should a Sales Brochure Underlie US Spectrum Policy?

Tuesday, March 29th, 2011

The FCC relies on Cisco’s forecast of mobile-broadband data demand as a basis for spectrum policy. Called the Visual Networking Index, it comes up many times in the National Broadband Plan, in other documents, and in speeches.


Stanford-developed Transceiver Operates Full Duplex on a Single Channel

Wednesday, March 2nd, 2011

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.


Experimental Radio Applications at the FCC

Wednesday, February 9th, 2011

This summarizes a selection of applications for the Experimental Radio Service received by the FCC during January 2011. These are related to land mobile radio, VHF propagation study, satellite communications, network-centric warfare, TV white space, software defined radio (SDR), military command and control, remotely piloted aircraft, LTE, radio direction finding, OpenBTS, Identification Friend or Foe (IFF), peer-to-peer communications, flight test telemetry, automotive telemetry, WiMAX, surveillance radar, vehicle radar systems, and millimeter-wave communications.


Experimental Radio Applications at the FCC

Monday, January 3rd, 2011

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.


FCC Seeks Input on Dynamic Spectrum Access

Wednesday, December 15th, 2010

As a prelude to proposing rules, the FCC is seeking comment on many issues related to dynamic spectrum access technologies, including how they can increase spectrum capacity and what the Commission can do to promote their use.


“Trusted” Academia Favored over Industry in FCC’s Proposed Experimental Rules

Wednesday, December 8th, 2010

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.


Experimental Radio Applications at the FCC

Sunday, December 5th, 2010

This summarizes a selection of applications for the Experimental Radio Service received by the FCC during November 2010. These are related to ultra-wideband (UWB), radar, TV white space, millimeter-wave, mobile satellite terminals, UMTS, military networking, microwave interferometry, flight test telemetry, public safety, and seismic data acquisition.


FCC Takes Further Steps toward Mobile Broadband in TV Spectrum

Thursday, December 2nd, 2010

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.


The FCC’s Spectrum Deficit Estimate

Monday, November 22nd, 2010

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.


The Spectrum Famine

Monday, October 25th, 2010

Mitchell Lazarus writes in the October 2010 issue of IEEE Spectrum on The Great Radio Spectrum Famine — the challenges of getting more spectrum for mobile broadband. He notes the importance of incentives that can lead users to optimize or reduce spectrum usage on their own. There is some great historical information as well. It is another informative and thought-provoking article from Mr. Lazarus, who can also be found from time to time on the CommLawBlog.

A comment of mine was posted along with the article today.  I copy my comment below:

Thank you Mitchell for sharing your insights and providing an important historical perspective. I had almost forgotten about the assignment by industry in two-way. Another scary tale if I run out of ghost stories this Halloween.

I, too, have followed the decline in terrestrial TV viewing for years. Today, though, I see more people “cutting the cord” and dropping cable or satellite. They use a combination of internet and over-the-air viewing. I wonder if this downward trend is ending.

In the Capitol Hill neighborhood in Washington, the local wireless internet service provider is now offering a service called “free TV.” You pay them $300 to put an antenna on your house and hook it up to your TV. Twenty channels with no monthly fee. They market this as an innovation, and it sells.

We see these large projections for future mobile broadband demand; a lot of that is video. Mobile operators have been working about 10 years to engineer and make a business case for broadcasting. Technically, they can make it work but it’s not a business yet, anywhere in the world, in part because of the system capacity tied up in providing the service.

In the hierarchy of mobile needs, I’d say voice is most basic closely followed by text. Video is nice, but less essential to my life. I’ll use it on my unlimited data plan. If a per-byte tiered-pricing plan is put in place, I may pass.  I’ll download it at home and move it to my phone. Or wait until I’m near a Wi-Fi hotspot.

I do believe in the next few years we’ll see some significant technologies that allow for more efficient spectrum use. Source coding technology will be one of those areas. There will also be better networking protocols for heterogeneous radio networks what will allow for more seamless handover among 3G, 4G, Wi-Fi, and even Ethernet; this will make it easier for operators to move off crowded mobile broadband spectrum whenever possible. Applications can be more tightly coded.

None of the above is meant to deter the search for more spectrum for mobile broadband. I like the FCC’s plan for the voluntary transfer, using financial incentives, of TV allocations to mobile broadband. As you suggest, incentives help. I like the suggestion involving a non-profit group. In addition, I wonder if spectrum can be made more like property; when people own something, then tend to take care of it and maximize its value.

One comment here suggests femtocells as part of the solution. Femtocells are a good fix to fill in coverage holes. From what I have seen so far, however, they won’t be much help with the spectrum crunch. Interference issues preclude ubiquitous placement.

FCC Finalizes White-Space Rules

Thursday, September 23rd, 2010

The FCC finalized its white-space rules today, acting on petitions for reconsideration of its earlier decisions. It issued an 88-page  Second Memorandum Opinion and Order that explains its decisions and includes the final white-space rules. A much-shorter press release was also issued.

At least one FCC observer has noted an uncharacteristic level of hype in today’s announcements. The FCC calls it “super Wi-Fi,” and adds the “potential uses of this spectrum are limited only by the imagination.”

Over two years ago, Google called it “Wi-Fi on Steroids.” It was later picked up by the popular press. Not all agree; it’s “Wi-Fi on Crutches” according to one who dares to consider the realities of physics and economics.

I’ll call it “Wi-Fi on Caffeine,” at least with respect to better range and coverage — if not data rates — compared with current Wi-Fi equipment. This is partly due to operation in the UHF-TV band instead of the 2.4 GHz band. In major markets and their suburbs, there will be few or no channels available for white space use. In rural areas and other less dense areas, the technology will be a good fit with Wireless Internet Service Providers (WISPs) and other longer-distance applications.

Cellular operators would like some of the white space on a licensed basis for backhaul in rural areas. They didn’t get it today, but the FCC is actively considering it and we may hear more on that by the end of the year.  No way are all these vacant channels going to be occupied by internet services in the most rural areas, so the proposal of the operators makes sense.

In IEEE 802, Working Groups 802.22 and 802.11 are working on standards that can be used by equipment in these applications; 802.22 may be the one with longer range. Working Group 802.19 is trying to facilitate coexistence between the two. Now, there are asymetric interference effects, which is causing friction between the two groups beyond the normal competition. (802.22 takes the harder interference hit.)

There will be other standards and equipment as well. The white space concept is international, but unique to each area of the world.

Equipment is not easy; it’s challenging to develop sufficiently-broadband power amplifiers and antennas, and to meet the emission mask in a cost-effective manner.

Another challenge is developing a business plan when 120 MHz of TV spectrum could be taken away under the National Broadband Plan.


Ultra-Wideband: How Regulatory and Standardization Delays Slowed a Wireless Technology

Thursday, September 2nd, 2010

The FCC recently issued an order denying reconsideration petitions in its ultra-wideband (UWB) proceeding. That effectively ends the 12-year UWB rulemaking process. Mitchell Lazarus recounts how UWB became bogged down at the FCC and in a failed standardization attempt in IEEE 802.

UWB, as authorized by the FCC, operates across 3.1 to 10.6 GHz, with very low power at any one frequency; its tendency to cause or receive interference is very low.

IEEE 802 attempted to create a UWB standard in IEEE 802.15.3a but did not, as neither of two competing proposals reached the necessary voting threshold for approval. One of the competing proposals, Multi-band Orthogonal Frequency Division Multiplexing (MB-OFDM), has since seen some consumer success in Wireless USB, which is based on a platform maintained by the WiMedia Alliance; data rates are up to 480 Mbps at a range of about 10 feet.

UWB was eventually standardized in IEEE 802.15.4a, where it exists as an alternative physical-layer to standard IEEE 802.15.4-2006, a standard for very low power, low data rate devices. (The IEEE 802.15.3 family is for higher data rates with higher power consumption.) It uses what was the other competing proposal in 802.15.3a, Direct Sequence UWB (DS-UWB). This standardized form of UWB has been commercialized for asset tracking and other location services, but not yet for consumer applications.

Cultural Barriers to Federal Spectrum Reform

Monday, August 23rd, 2010

As the FCC searches for more spectrum for mobile broadband services, its National Broadband Plan points to federal spectrum as a candidate. Since the National Telecommunications and Information Administration (NTIA) is responsible for allocating federal spectrum, the FCC can’t do much more. Still, the FCC’s recommendations are good. One is for the FCC and NTIA to “develop a joint roadmap to identify additional candidate federal and non-federal spectrum that can be made accessible for both mobile and fixed wireless broadband use, on an exclusive, shared, licensed and/or unlicensed basis.” In support of that, the “FCC and . . . NTIA should create methods for ongoing measurement of spectrum utilization.”

Variations of these proposals have been around for decades, formally and informally. Once in a while, progress is made. In 1995, NTIA suggested the changing the 3650-3700 MHz band from federal-only to mixed-use (federal and non-federal). That happened, and in 2005 the FCC adopted rules that resulted in the creation of the IEEE 802.11y standard. (That allows high-powered Wi-Fi equipment to operate on a co-primary basis in the 3650-3700 MHz band in the US, except when near certain satellite earth stations.)

So, it can happen. That, and recent FCC talk of “unleashing” broadband made me think the above recommendations in the FCC’s Plan might get some traction. I’m less sure now after following the latest writings on the topic by spectrum expert Michael Marcus.

In an August 17 post on his blog, Marcus asks why NTIA isn’t measuring occupancy of the almost exclusively-federal 225-400 MHz band. He finds that the Interdepartment Radio Advisory Committee (IRAC), NTIA’s advisory committee of federal users, is concerned that measurements in major cities – where spectrum is most needed – will show low occupancy because the band is primarily used by military aircraft. Marcus says enough with these delays; in the new era of cognitive radio and dynamic spectrum access technology, it’s time to see some hard spectrum data so sharing options can be examined.

If you’re intrigued by that, there’s more. An August 9 post says an NTIA spectrum advisory committee “evades some major issues and pushes the parochial agendas of some committee members without trying to relate them to the broader public interests.” A May 10 post takes you inside that committee’s meeting, and observes a general effort to protect incumbent spectrum users.

It can happen, but these reports suggest the timetable will be later rather than sooner.