Wrong Wavelength

Overcrowding in the radio frequency spectrum threatens national security and the economy.

T

hat oxygen is to life, the radio frequency spectrum is to modern living. While few of us have a very firm grasp of the principles of electromagnetic radiation, most of us would have a tough time getting by without the technologies that depend upon it. Without the ability to send and receive radio signals over the airwaves, there would be no cell phones or pagers, no National Public Radio, no "NewsHour" with Jim Lehrer, no "West Wing." You couldn't withdraw cash from an automatic teller machine. And if you're one of those thoroughly modern creatures who uses a Blackberry or a Palm Pilot or who sends e-mails from a cell phone, you might just as easily move to another planet as try to get by without access to the radio frequency spectrum.

While ordinary folks have unwittingly become voracious consumers of the radio spectrum, which is the primary vehicle for wireless communications, advances in military technology have made the Defense Department positively gluttonous in its appetite for spectrum. Mobile wireless communications form the backbone of modern warfare, making the U.S. military stronger than any other force on the globe. Although militaries have for decades relied on radio communications to operate effectively, the more recent ability of far-flung troops to call in air strikes with pinpoint precision, or of military commanders to orchestrate battles being fought several time zones away, is the result of a remarkable confluence of technologies-most of which depend upon access to those invisible airwaves in the radio frequency spectrum to operate fully.

Because spectrum is a finite resource, the military's need for it has run headlong into the needs of the telecommunications industry, which has not only convinced 130 million Americans they can't live without cell phones, but is working on a slew of other must-have devices to lure the rest of us. And the telecommunications industry is probably right, although perhaps not in quite the way their marketing departments would have us believe. Information is like a drug. Once you've had it, it's tough to live without it, and the more you get, the more you want.

Consider the special operations sergeant in Afghanistan tracking terrorists through unfamiliar terrain. A few years ago he might have been content with a good map, a reliable radio and a pair of binoculars. Today, he relies on the Global Positioning System of orbiting satellites to precisely target his enemy. And his commander might not be content with a verbal report from the battlefield, especially if he could watch events unfold live on video shot from an unmanned aerial vehicle on the scene. On a more mundane level, consider the reactions of most office workers if told they had to function without e-mail or voice mail.

Michael Gallagher, deputy assistant secretary for communications and information at the Commerce Department's National Telecommunications and Information Administration, says the number of subscribers to mobile wireless services has doubled over the last five years and is growing at a rate of about 20 percent a year. Two-thirds of productivity gains in the American economy over the last decade came from technology and telecommunications innovations, Gallagher says. As communication devices get smaller, cheaper and more powerful, more and more people find they can't live without them.

If America's economic success depends on expanding access to radio frequency spectrum, so too does the nation's security, and not just the kind of security that's provided by military might or a robust economy. Wireless communications are becoming vital to law enforcement agencies and emergency responders. As homeland security requirements are bolstered and refined in the coming months and years, spectrum management will become increasingly contentious. What's more, U.S. domestic spectrum policies have international implications for both national security and the global economy.

The big problem in this growing dependence on radio frequencies is that there's only so much usable spectrum out there, and more people want access to it to move larger amounts of information more quickly. While experts disagree over what to do about it, they all agree the situation is unsustainable. Sooner or later, something will have to give.

MANAGEMENT HEADACHE

Despite the critical importance-and scarcity-of spectrum, the United States has no national strategy to manage it. The methods used to manage it today stem from the 1934 Federal Communications Act, which established the Federal Communications Commission as an independent agency with broad regulatory power over both wire-based communications, such as telephone

and telegraph systems, and radio-based communications. The law also gave the president the authority to assign frequencies to all federally owned and operated communications-authority that is now vested with the assistant secretary of Commerce for communications and information.

In 1978, President Carter established the National Telecommunications and Information Administration at Commerce to manage the federal government's use of radio spectrum. In essence, NTIA manages spectrum used by federal agencies and answers to the president; the FCC manages spectrum used by the commercial sector and state and local governments, and answers to Congress.

Spectrum is divided into broad categories designated for certain types of communications, such as fixed, mobile, broadcasting and satellite services. Categories are further designated for government, public safety, business and commercial uses. While the Federal Communications Act essentially split control of spectrum between the FCC and the Commerce Department, the law does not allocate specific bands of frequency to the federal government. NTIA and the FCC have reached agreements dividing the spectrum between government and the private sector.

Until about the mid-1980s, spectrum was widely available. Those who wanted to use a portion of the spectrum simply had to fill out the proper paperwork with the FCC and buy a license to operate in a particular bandwidth. But the proliferation of wireless technology changed all that. For years now, virtually all the usable bandwidth on the spectrum has been allocated. In order to make room for more users, existing allocations have been redefined, frequently at the expense of the military, which has long been viewed by the private sector as an inefficient user of spectrum.

Rebecca Cowen-Hirsch, director of the Defense Spectrum Office and the Defense Information Systems Agency, says the military measures efficiency differently from the private sector. "For our purposes, efficiency is not translated in the strictest sense in terms of the amount of money you can make in relation to the amount of spectrum you're using, either by a customer base or by what price you'll pay for certain amounts of spectrum. Efficiency for our purposes is translated as effectiveness-the ability to be able to get the information from point A to point B. There are some environments where it's important that you do everything possible to ensure that information gets from point A to point B-it's really a matter of life and death. That's an inherently inefficient, yet infinitely effective, capability."

Over the last 10 years, under pressure from the telecommunications industry and a willing Congress, the Defense Department and other federal agencies have seen their share of spectrum erode. Private firms have been willing to pay big bucks for some of the most desirable frequencies in the spectrum, and the Clinton administration and Congress were happy to oblige-the auctioning off of spectrum controlled by federal agencies was a critical element of balancing the federal budget in the 1990s. The Bush administration is now reviewing plans to auction off an additional portion of the spectrum occupied by Defense.

But Defense officials are concerned that the government may be relinquishing control of too much spectrum. In January, Defense Secretary Donald Rumsfeld created a senior post at the Pentagon for spectrum management and named Steven Price as the first deputy assistant secretary of Defense for spectrum and C3 (command, control and communications) policy. Price, the former president and CEO of the software firm LiveWire, is taking a hard line on spectrum management: "I would argue that not only do we need all the spectrum we currently have access to right now, but we need more spectrum," Price says. "I don't accept the premise that we will have to give up more spectrum." Not only is the military's reliance on spectrum-hogging technologies increasing, but Defense's expanding role in homeland security-protecting U.S. airspace, providing security at high-profile events-is exacerbating the bandwidth crunch it was already feeling, Price says.

LIMITED RESOURCE

To understand the challenges of managing spectrum, it's helpful to understand something about the electromagnetic radiation that permeates the atmosphere. Electromagnetic waves propagate outward in all directions-as you read this, you are being bombarded by such waves, and thanks to that portion of the spectrum in which visible light exists, you can see to read this. The electromagnetic spectrum extends in either direction from the visible range, and just as waves in water can be measured by the distance between wave crests and by the frequency with which the crests pass a point in a unit of time, so too can electromagnetic waves be measured. Radio waves are a form of electromagnetic radiation that result from oscillations of particles; the number of oscillations per second refers to frequency, and is measured in units of "hertz," with kilohertz measuring thousands of hertz, megahertz measuring millions of hertz and gigahertz measuring billions of hertz. To send and receive signals across the radio spectrum effectively, transmitters and receivers are designed to operate at particular frequencies.

The entire radio spectrum ranges in frequency from 3 kilohertz to about 300 gigahertz in the United States (other nations define the radio spectrum differently). Although radio spectrum spans some 300 billion frequencies, 90 percent of its use is concentrated in the lowest 1 percent of frequencies. The most desirable real estate in the radio spectrum includes the bands in the lowest frequencies-those that fall below 3.1 gigahertz. These frequencies are ideally suited for mobile wireless communications because signals traveling at these frequencies can travel farther with less power than signals traveling at higher frequencies. A soldier carrying a tactical radio that operates in one of these lower frequencies won't need to lug around heavy batteries and huge antennas on the battlefield. Only about 15 percent of the most desirable spectrum is reserved exclusively for use by the federal government. And of that 15 percent, less than half is controlled by the military.

Spectrum is only useful if those using it cooperate for maximum benefit. Otherwise, users would interfere with each others' signals. And while spectrum is considered a national resource and its local management is the sovereign right of nations, radio waves don't recognize national boundaries, making international cooperation and coordination of spectrum usage essential. The United Nations, through the International Telecommunications Union, manages international spectrum agreements whenever communications signals extend beyond a nation's borders, which is often the case when satellite communications are involved. Nations must register their requirements with the ITU-a process that can take years. The ITU approves requests on a first-come, first-served basis, provided the requests comply with the internationally accepted Table of Allocations, which designates that certain portions of spectrum can be used for certain communications.

Not surprisingly, just as spectrum management in the United States has become more difficult as more users compete for limited space, international spectrum management also has become increasingly complicated. Pressure to reach agreement on spectrum designations for wireless devices to operate worldwide is growing as consumers want more communications devices that function around the globe. Likewise, the military is finding it increasingly difficult to reach agreements with host nations and coalition partners when operating overseas.

The Defense Science Board, in its November 2000 report "Coping with Change: Managing RF Spectrum to Meet DoD Needs," found that problems with radio frequency spectrum allocations hindered military operations in the 1999 Kosovo campaign: "Imagine trying to win an overseas air war where target intelligence can be gathered only part of the day, where aerial refueling is hampered by inability to fly in close formation under prevailing weather conditions, and where many newly developed radio systems for air, sea and land forces don't work the way they did back in the U.S.? Sound unlikely? It isn't-these constraints limited the U.S. forces' ability to operate to maximum efficiency during the Kosovo campaign."

Thomas Sugrue, chief of the wireless telecommunications bureau at the Federal Communications Commission, says the current situation can't be allowed to continue. At a June hearing of the Senate Commerce, Science and Transportation Committee, Sugrue said, "Our nation has become dependent on spectrum-based services, which have brought great benefits in the form of enhanced efficiency, greater security and an overall improvement in the quality of life of our citizens. In terms of spectrum needs, though, the wireless revolution is becoming a victim of its own success. The simple truth is that, as our society grows increasingly dependent on wireless technology and services, spectrum demand is stressing the supply."

GROWING CONSTRAINTS

Joe Capps, director of the Army Spectrum Management office, is more familiar than he'd like to be with the stress that demands for spectrum are placing on the supply. It's Capps' job to make sure that soldiers being trained in the United States can use their radios and other communications equipment without interfering with local air traffic control frequencies, cell phone operations or any other of a hundred different possibilities. Because the Army shares radio frequencies with the other military services, other federal agencies, and, in some cases, with the private sector, avoiding frequency conflicts is as much an art as a science. Capps and his staff across the country work hand in glove with spectrum managers from the other services and other federal agencies to keep military communications equipment working as intended.

"Our customers don't know the allocation rules," Capps says. Even if they did, it would be a full-time job sorting through them. At his office in Alexandria, Va., Capps points to the radio frequency spectrum allocation chart, a colorful mess of lines and boxes intended to illustrate how the portion of the electromagnetic spectrum suitable for transmitting radio signals has been haphazardly divided up between federal agencies and the private sector: "That's 60 to 70 years worth of Band-Aids," he says.

Certain areas of the spectrum are so crowded that virtually every request Capps' office gets has to be modified. To military troops, who sometimes can't use their equipment in training as they would expect to use it in battle, this is significant. "The thing every soldier expects to be able to do-needs to be able to do, really-is to train as he would fight. That doesn't always happen," Capps says.

Even testing new equipment can be extraordinarily difficult. When the Air Force conducts telemetry flight tests of F-22 fighter jets in Southern California, a single aircraft, with its state-of-the-art communications equipment, eats up so much of the available spectrum that the service has to stop all other military flights in the region.

DOMINO EFFECT

The wireless industry and some members of Congress are pushing the military to retool some of its equipment and move its operations to new frequencies in the spectrum, freeing up more space for industry in that part of the spectrum most view as essential for creation of the next generation of wireless devices.

To do so would be both incredibly complex and expensive. For example, Price says, the Air Force's Airborne Warning and Control System aircraft have 50 different antennas that communicate with various communications platforms and equipment in space, on the ground and on other aircraft. Changing any one of those frequencies could affect the operation of everything else. In addition, changing links to satellite communications is virtually impossible in some cases without replacing the satellites, an extraordinarily expensive and complex task.

"I'll give you another example of why this is so difficult," Price says. "U.S. Central Command just reached an agreement with one of our allies to be able to use radios in that country-after six years of negotiations. If you make us give up those radios, will we have to wait another six years to operate in that country? I don't know. Maybe. And what do we tell our allies, who have purchased equipment to be interoperable with us? Who pays for them to replace their radios with new ones? This is incredibly complicated stuff and there are no easy solutions."