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Remarks of NTIA Chief of Staff Thomas Power at the 12th Annual ISART Conference

12th Annual International Symposium on Advanced Radio Technologies
Boulder, CO
July 28, 2011

- As prepared for delivery -

Good morning and thank you for joining us today. NTIA is pleased to be hosting this 12th Annual International Symposium on Advanced Radio Technologies here at our research and engineering laboratory in Boulder.

As many of you know, NTIA is the principal advisor to the President on communications and information policy. Although Federal spectrum policy has always been a core mission of this agency, our work on spectrum issues is more important now than ever before as spectrum is fast becoming a pillar of America's digital infrastructure. Spectrum has enabled the mobile broadband revolution, changing the way that Americans communicate and do business.

Last year, ISART provided a platform for a broad range of perspectives on spectrum sharing. The focus of this year’s conference on radar bands is a great place to further this dialogue.  Radar bands have frequently been identified as candidates for sharing and radar technologies are a key factor in our work surrounding future spectrum policy making and our ongoing federal spectrum management efforts.

In my remarks today, I would like to first discuss progress NTIA has made in response to the President’s Executive Memorandum to make available 500 megahertz of Federal and nonfederal spectrum over the next 10 years. Next I will look at how our work here relates specifically to radar technologies and uses. Lastly, I will point out several points for consideration related to how our work in this area, and our approach to radar bands specifically, might be shaped to maximize efficient use and the benefits to the American people.

With the rapid growth of mobile broadband, it should come as no surprise that President Obama and policymakers have made it a key priority to increase the amount of federal and commercial spectrum available for mobile broadband.

To expand America's available spectrum resources, we know the government must use its existing spectrum more efficiently, we must free up more spectrum for new uses, and we must provide the private sector with the incentives to transfer spectrum from current uses to higher-value ones.

President Obama’s State of the Union address this past January contained significant news on the spectrum front. The President called for a National Wireless Initiative to make available high-speed wireless services —the “4G” technology now being deployed in the United States by leading carriers—to at least 98 percent of Americans. The President’s initiative will make it possible for businesses to achieve that goal, while freeing up spectrum through incentive auctions, spurring innovation, and creating a nationwide, interoperable wireless network for public safety. 

A critical component of the National Wireless Initiative is the President's directive to NTIA to collaborate with the Federal Communications Commission (FCC) to make available 500 megahertz of Federal and nonfederal spectrum over the next 10 years.  The initiative – to nearly double the amount of commercial spectrum over the next decade -- will spur investment, economic growth, and job creation while supporting the growing demand by consumers and businesses for wireless broadband services. 

To make this happen, the President directed the Secretary of Commerce, working through NTIA, to collaborate with the FCC to produce a ten-year plan and timetable for making available the 500 megahertz of spectrum, all while protecting vital government missions that rely on spectrum use.

Pursuant to that directive, NTIA delivered to the White House, within three months, a plan and timetable for performing this work. In November, NTIA released two complementary reports. First, we issued the Ten-Year Plan and Timetable. This report, developed with input from other Federal agencies and the FCC, identifies 2,200 megahertz of spectrum for evaluation, the process for evaluating these candidate bands, and the steps necessary to make the selected spectrum available for wireless broadband services.

In addition, NTIA released a second report -- the results of a fast-track review we undertook to identify some spectrum reallocation opportunities that exist in the next five years. This allows us to make a down payment on the President’s overall 10-year goal.  Our report identified and recommended a total of 115 megahertz of spectrum to be made available for wireless broadband use within five years, contingent upon the allocation of resources for necessary reallocation activities. 

And we continue to make progress on the President’s spectrum initiative.

Earlier this year, we selected the next spectrum band to be evaluated for potential repurposing to commercial use. The band we selected with input from other federal agencies, 1755-1850 MHz, is a priority for review based on a variety of factors, including industry interest and the band’s potential for commercial use within 10 years. We plan to complete our review of this band by the end of September. This spring we also issued our first status report on the overall progress of the 500 megahertz initiative.

Traditionally, calls for more spectrum have led to Federal agencies’ being required to relocate operations to free up spectrum for commercial users. But today, it is not so simple. Meeting the goals of the president’s memorandum will require the reallocation of spectrum from both commercial and Federal users. Moreover, many of the bands that will be considered in this effort will involve sharing of some sort. 

My boss, Assistant Secretary Strickling, has been very vocal about arming agencies with adequate resources for Federal relocation activities, especially upfront planning expenses.

Last month he testified on Federal government spectrum use and reiterated the importance of supplying agencies with the necessary funding to plan for reallocation as well as to investigate more efficient spectrum-sharing options. We believe that funding is critical for agencies to maximize their efficient use of spectrum resources. However, I’m pleased to report that we are encouraged that legislation recently reported by the Senate Committee on Commerce, Science, and Transportation makes important strides in better accommodating the costs of relocating Federal users.

While solutions such as spectrum re-allocations are critical to meeting national needs, so is the development of the next generation of technologies that can enable more efficient use of the radio spectrum. NTIA, along with its Federal agency partners, is committed to developing and improving new and innovative spectrum sharing capabilities to further our mission of increasing the efficiency of Federal spectrum use.

In step with this, on Tuesday here in Boulder, the Wireless Spectrum Research and Development Senior Steering Group, which was formed to coordinate spectrum-related R&D activities across the Federal government, hosted a technical workshop to coordinate Federal and private sector research to help identify R&D opportunities  that may have large potential payoffs for the national wireless industry and the nation’s economy at large and which are consistent with the Federal Government‘s development goals and lay the framework for long-term research that may result in yet-to-be-conceived improvements in spectrum utilization.

Thank you to NTIA’s own Byron Barker who co-chaired this group. We look forward to reviewing the resulting report from this workshop.

We are also working with our non-Federal partners to ensure our spectrum efforts reflect the needs of stakeholders. Yesterday, the Commerce Spectrum Management Advisory Committee met here in Boulder to review progress on the President’s ten-year plan and highlight priorities of industry and non-Federal stakeholders.

In our effort to address the President’s spectrum initiative full circle, additionally we are working closely with the White House and Congress to move forward incentive auctions to open broadcast and MSS spectrum.

As you can see, there is much work to be done but we are working aggressively toward the President’s goal.  So, after we complete our review of the 1755-1850 MHz band, where do we look next?  We have been working with the agencies to prioritize our review.  We will be evaluating opportunities for making spectrum available for wireless broadband.  This may include bands from which we might relocate incumbent systems or spectrum where sharing between incumbents and wireless broadband is possible whether licensed or unlicensed.

Our search quickly draws us toward radars and radar spectrum.  Your focus at this conference is timely for our work.  I look forward to the next couple days of discussions.  I want to encourage you to push the envelope to stir ideas regarding how we can make use of this spectrum to meet our broadband goals while ensuring that the missions supported by radar technology continue to be met.

So why are radars and radar spectrum so important to our work to identify spectrum for wireless broadband?  Of the 2263.9 MHz identified for review by NTIA and the FCC within our 10 year plan, 1240 MHz of that or almost 55% is spectrum currently used for radar operations.  Not all of that spectrum is federal exclusive.  Most of it has some sort of non-Federal allocation.  But the reality is that the federal presence dominates most of these bands.  Let’s take a look at which bands we are talking about.

The 1300-1350 and 1350-1390 MHz bands, taken together support the aviation and defense communities use of radars for long range air surveillance for air route flight control in a friendly environment and target tracking when needed in a tactical environment.  We are talking about approximately 400 radars that reach out 200-400 miles to monitor air traffic across the country.  Many of us remember during 9-11 the pictures of the “big board” that the FAA uses as a national composite picture of the whereabouts of all air traffic.  This picture is drawn from this data.  It supports the regional air traffic centers’ ability to direct traffic.  These systems represent a significant investment in our air traffic safety infrastructure. Furthermore, while modern communication systems (especially commercial wireless) have rapid development cycles (a couple years at most), radars last for decades. This makes it difficult to modify and evolve radars in a timely fashion. Defense use, while also supporting air traffic management, has a critical tactical role since they also double in terms of tracking aircraft and other potential airborne threats.  In recent years, radar use in this range has expanded as we have added aerostat-borne radars to our tool chest in our efforts to interdict drug smugglers and secure our borders.  We understand that this frequency range offers significant advantages in being able to provide range and resolution needed to support these functions.  Reaching these long distances through heavy rain at higher frequencies presents challenges.

The 2700-2900 MHz band also supports airport air traffic control all around the country.  However, in this case, it represents the take-off and landing approach control, moving our aircraft efficiently and safely in and out of about 700 airports.  At the same time, the weather community uses this band for almost 200 weather radars that support our weather prediction and storm tracking efforts.  As we have witnessed this past year the destruction caused by tornadoes and other violent storms, we can see clearly how critical the warnings that these systems provide are to the saving of lives.  Families are now able to watch reports on television and make necessary safety preparations.

Some of these weather radars also operate above 2900 MHz as the spectrum below 2900 MHz becomes more congested.  However, the 2900-3100 MHz band is predominantly used by the maritime community to operate radar devices on ships for navigation.  In addition to providing detection of other ships and terrain obstacles, these radars also trigger radio beacons, the electronic equivalent of the light house.  These modern tools are more widely distributed, unmanned and require significantly less real estate.  But they do require spectrum.

Mobile military radars begin at 2900 MHz and go up through 3650 MHz to meet a variety of missions.  The systems include air and ship borne operations, and effective radiated power levels often exceed a gigawatt.  We understand that in the current tactical environment, these radars must also be flexible and jam resistant.  For that reason, they use techniques that make them more difficult for the enemy to pin down.  However, this quality may also make difficult the formulation of sense and avoid strategies for spectrum sharing.  At the same time, the high levels that they emit would probably cause interference to broadband wireless operations.  Airborne operations would spread that interference over very large areas.

So these are the bands that we have to review.  We face some tough questions in looking at them and hope bringing together experts like you will help us to understand what we can do.

  • Can any of the missions be accomplished in higher bands?

We understand that there are technical links between radio applications and their preferred operating bands.  Because existing radar designs take advantage of atmospheric propagation, changing bands can be problematic. Use of higher bands means needing to cope with different, and often worse, propagation for a given mission.  However, some of these bands were probably selected as the next available band as we were marching up the spectrum with new developments.  Are there new techniques that would allow us to move higher and overcome limitations?  What is the timeframe and cost that would be required for real redesign?

  • What will be the impact of GPS and other radio navigation satellite systems on requirements for aviation via NexGen and for maritime radars?

Most people assume that with the widespread availability of GPS and the development of NEXGEN that some radars will not be needed.  However, radars have the unique characteristic of being active, self-contained systems for sensing surrounding environments. For tracking aircraft, for example, radars do not depend on beacon replies or GPS-based information from aircraft cockpits. Instead, planes can be followed even if beacons are switched off or fail (as happened on 9/11) or GPS based information is not available.  For maritime navigation, ship borne radars show mariners other vessels and hazards which cannot be located using charts and beacons in conjunction with GPS. This is not to preclude GPS and beacon-based solutions for aeronautical and marine navigation, but radar provides fail-safe capabilities that the aeronautical and marine communities currently rely on.

  • Can we be more efficient in packing radars together?

Our tools for selecting radar frequencies for fixed location radars probably need to be updated. Many or our “rules of thumb” were developed long before our computerized modeling and terrain information came into being. If we can pack these bands more closely, then possibly we can free some of this spectrum.

  • If we can cut out a portion of these bands, and implement wireless broadband, can these services live with each other as close neighbors?

We understand that radar signals are not clean.  Many radars are fairly old and their receivers were designed during times when they had no neighbors.  We also have seen some indication that broadband systems also have challenges in reducing levels outside their operating band.

  • Can new systems share with radars? By geographic location or by sensing or other time sharing methods?

As I have said, there are a lot of megahertz set aside for radar operations.  We have some experience with WiFi sensing radars and we expect to see more tools available for using geolocation databases to support sharing.  Experience gained with Dynamic Frequency Selection (DFS) communication systems sharing spectrum with 5-GHz weather radars has provided valuable lessons that can be applied to future band sharing technologies. While some compatibility problems have occurred with DFS at 5 GHz, many DFS systems currently share spectrum with weather radars without causing interference. In cases where interference has occurred, engineering solutions have been developed or are within reach. The DFS experience has provided technical staff and policy people with new knowledge regarding certification testing and enforcement processes that can be applied to future dynamic sharing.  Geolocation databases have potential in some circumstances, but challenges will need to be overcome regarding data release on radar characteristics and locations. Many government radars are classified, and many unclassified radars cannot have their frequencies and locations made available in public listings.  We are not sure whether sharing with fixed radars opens sufficient geographic areas to provide significant access. Geolocation by itself cannot support sharing spectrum with mobile radar incumbents. With mobile radars, you have some hope that the intermittent operation may allow access to most locations for most of the time via sensing. 

  • Is the commercial wireless industry interested or able to share in radar spectrum?

In the end, this is a critical point.  We need to free up spectrum in workable chunks.  Ultimately, the question of whether industry will find sharing approaches feasible will depend on the amount of spectrum that can be made available, where it is available and for how much of the time.

Frequently, as we discuss spectrum, we view things from a communications technology perspective and often a perspective that is limited to land mobile or even cell phone techniques.  The community and policy makers must begin to understand the challenges and constraints that currently exist for radar.  Radar transmitters are more powerful than most communications systems (sometimes more than a gigawatt radiated power) making them a potentially greater source of interference.  Also, radar receivers are more sensitive than most communications systems (e.g., receiving 1/100 picowatt of echo energy from targets at 80 miles range) making them more vulnerable to interference.

Those of you with skills and knowledge in radar technology are critical to our efforts.  I want to encourage you to roll up your sleeves.  Be creative in your efforts.  Get your ideas out on the table.  Let’s look for how we can increase use of the spectrum and not just get trapped by all the reasons, all the barriers that limit us.  We are working at a critical time and your work is a key part of this effort. I look forward to a healthy discussion over the coming days in continuation of the collaboration between government, industry, and academia that has always marked ITS’ activities.