Future Anti-Missile Research Directed to Countermeasures.

Despite the Bush administration's bullish outlook on the deployment of a missile-defense shield during the next decade, there is a lot of work yet to be done in the laboratory, said U.S. government scientists.

The United States could end up spending between $20 billion and $100 billion to deploy ground-, air-, sea- and space-based anti-missile weapons during the next two decades. The goal is to be able to intercept and destroy in flight, both tactical and intercontinental ballistic missiles that would be launched by potential enemies, such as Iraq, Libya or North Korea.

But it would be foolish to deploy such anti-missile systems unless they were intended to defeat not just the rogue-nation ICBM blitzes that U.S. intelligence agencies predicted will occur in the decades ahead, but also more advanced threats and sophisticated countermeasures that may not have been conceived yet, these scientists said.

Among the most challenging technological problems confronting the U.S. missile-defense program, they explained, is the development of more capable sensors and interceptor weapons that can counter multiple targets simultaneously, accurately discriminate between warheads and decoys and put enough kinetic energy on the target to destroy it.

The so-called "hit-to-kill" technology--based on the notion that a warhead (nuclear, chemical or biological) can be destroyed by smashing a high-speed projectile against it--has been tested quite extensively in the past 30 years, said Darrell Collier, chief scientist at the Army Space and Missile Defense Command.

During a question-and-answer session with reporters in Huntsville, Ala., Collier acknowledged that mounting criticism about the lack of emphasis on countermeasures has prompted U.S. program officials and scientists to focus more attention on this issue. Countermeasures are techniques--such as decoys, chaff and jamming--designed to fool an interceptor. But Collier cautioned that those who accuse the U.S. government of not doing enough work to address countermeasures may nor be informed enough, given that "countermeasures is a very difficult subject to discuss in the open." Much of the technology related to countermeasures is classified, Collier said.

Nevertheless, he said, "It's beneficial to be reminded that you've got to work this problem in a very uncertain environment--and that the guys on the other side might well be thinking of these. ... With countermeasures, we have to make investments and keep working. It's not a dosed universe."

The idea that a kill vehicle is largely ineffective unless it can discriminate between warheads and decoys has led to new requirements in the missile-defense arena that had not been addressed in the earlier years of the program, Collier said. In the 1960s and 1970s, he said, scientists worried primarily about chaff and jamming. "Decoys were not considered back then."

In an attempt to address critics' concerns, the Army and the Ballistic Missile Defense Organization have created a program called Hercules. Its purpose is to capture the data produced in tests thus far, in the form of engineering simulations, sensor data and algorithms that may help design more sophisticated weapons and counter-countermeasures. "Hercules was a direct response to those outside pressures [from critics]," said Collier.

Some of that pressure came from the Pentagon's former director of operational test and evaluation, Philip E. Coyle. In a 2000 report he wrote before leaving the government, he noted: "Decoys that provide a close representation of the RV [re-entry vehicle] or modify the RV signature have only been minimally investigated" by the U.S. missile defense program. U.S. officials, he added, also have failed to study the use of "simple, unsophisticated countermeasures" such as tumbling RVs and non-spherical balloons."

He charged that the Pentagon oversimplified the flight tests by removing decoys. The interceptors used in rests, Coyle said, had been programmed with "detailed information about the target suite--required to execute the discrimination algorithm--before the flight test was performed."

Among the most widely publicized criticism came from Massachusetts Institute of Technology physicist Theodore A. Postol, who contended that BMDO manipulated test data, in order to show that the kill vehicle could discriminate between a warhead and a decoy.

According to Collier, the Army and BMDO scientists assigned to the program are devoting more attention to the technologies involved in discrimination.

"We have a large database of observations from both radar and optical experiments that have been flown over 30 years," he said. There are, for example, about 1,200 radar observations that could be used to improve current discrimination technologies. The radar data--collected between 1962 and 1985 from various systems--is managed at the Defense Department's Lincoln laboratory, located at Hanscom Air Force Base in Lexington, Mass. The Massachusetts Institute of Technology manages the lab.

Optical data amassed between 1986 and 1996 was compiled under a program called "optical discrimination and analysis," said Collier.

The Hercules program will combine the optical and radar data into a repository that will be made available to scientists and program managers. There will be "red," "white" and "blue" teams, each of whom will postulate target complexes, formulate algorithms and "see whether the algorithms work," Collier said. "You can conceive of things we don't have radar data for. We can model any package that you want."

The algorithms can come from "any source," he said. "There is a community of people in the classified arena who are constantly thinking about algorithms and countermeasures. ... One reasonable accusation about our community is that we were ignoring the simple things that people could do (with countermeasures). So it's good to get some perspective."

One potential advantage for the U.S. missile-defense program, said Collier, is that it will be based on a multi-layered system. This makes it difficult to develop countermeasures that can address all layers at once, he added. Under the Bush administration plan, the goal is to deploy weapons that can hit enemy missiles shortly after launch (the boost phase), in the midcourse phase and the terminal phase. Some of the weapons will work inside the atmosphere and others in outer space. "It's hard to do a countermeasure that will handle both," said Collier. "The enemy would like to know which one he has to face. ... With layered systems, the enemy doesn't know if he is going to get hit in the boost phase, the early ascent phase, or if he needs to provide countermeasures to survive the re-entry" into the atmosphere.

A senior Navy official, meanwhile, downplayed the prospect of countermeasures becoming an Achilles' heel for U.S. missile defense systems. Capt. Leonard Capello, assistant chief of naval operations for missile defense, told reporters in Huntsville that the threat of countermeasures often is exaggerated.

"We talk about decoys, we talk about countermeasures. But there aren't a whole lot of those out there right now," said Capello. "[But] we have to prepare for the eventual development of countermeasures."

The Navy is developing new technologies to improve its sea-based missile-defense system, which only is designed to counter tactical short-range threats. Capello said there are no plans to upgrade the Navy system to defeat ICBMs, because that would be prohibited by the 1972 Anti-Ballistic Missile Treaty. Such an upgrade also would require the development of a brand-new missile, much larger and faster than the current SM-3 (the Navy's most advanced Standard missile).

Among the technologies sought by the Navy is a two-color seeker for the SM-3. A two-color seeker combines the information from two different wavebands of the infrared spectrum to perform RV-decoy discrimination.

The U.S. Navy also is working with Japan to develop a lighter nosecone for the SM-3. There are plans to explore new X-band radar technology in partnership with European allies, said Capello. X-band radar is considered a prerequisite for any system that must perform RV-decoy discrimination.

"We don't have any agreements to co-develop any radar with Europe or Japan, but we are discussing it," he said.

The Army Space and Missile Defense Command also is proposing two-color seekers as a technology that would help improve the accuracy of missile interceptors. The ideal combination would be a two-color seeker with a laser radar, said Jess Granone, the director of the command's technical center. Laser radar helps detect small movements, he said, thus aiding in the discrimination of RV vs. decoys.

To increase the likelihood that the real warheads, and not the decoys, are destroyed, Granone advocates the development of "miniature kill vehides," several of which could be packed on an interceptor. The Army and BMDO are cooperating on this program, he said. The technologies that must mature in order to make miniature kill vehicles include micro-electro mechanical inertial sensors, compact lightweight optics, miniaturized propulsion, energetic materials and focal plane algorithms, Granone said.

Missile-Defense Holy Grail: A Joint Tactical Air Picture

Sandra I. Erwin

The Defense Department needs to spend more dollars on advanced software, in order to link missile-defense systems from various military services, said Army Maj. Gen. Larry J. Dodgen. A joint air-defense architecture has been talked about for years, but has proven an elusive goal, he said.

"This whole business is about software. And software does not come cheap," he said.

Dodgen recently served as director of the Joint Theater Air and Missile Defense Organization. He is now the commander of the Redsone Arsenal, in Huntsville, Ala. The JTAMDO is a $17 million agency created by the Pentagon to promote interoperability among the services.

A joint command-and-control system would drastically boost the capabilities of existing weapons to defend U.S. troops and allies against enemy ballistic and cruise missiles, Dodgen told reporters during a briefing in Huntsville. He said that cruise missiles should be viewed as a compelling threat, because they typically fly low and are difficult for any single radar to detect them. Determining their launch point also is difficult, he said. An integrated command-and-control network linking all the services, each of which has separate missile-defense systems, would help "defend against more capable ballistic missiles and low-flying cruise missiles," Dodgen said.

The idea is to expand the "fire engagement zones,' he explained. Because each weapon system today works independently, a fire engagement area is limited to a single weapon. That limits the range of those weapons to "onethird of what we are paying for," he said.

"We need a joint engagement zone to shoot to maximum range," Dodgen said. "I don't think we are spending enough money on the integration" of weapons such as the Army's Patriot PAC-3 airdefense system with other air-defense assets from other services.

A joint command-and-control software-based system is scheduled to be tested this month in Dahlgren, Va., as part of a so-called joint distributed engineering plant, or JDEP. The Navy conceived the DEP as a simulation test-bed to test interoperability within a carrier battle group.

"We are trying to hook big pieces of the architecture together, with very high speed data links," Dodgen said. A simulation of that architecture then would be used to test other systems, over time. "We want to create a repeatable object so that we can fight a particular segment of the battle over and over" he said.

The JDEP event scheduled for this month will test the interoperability of the Navy's Aegis cruisers with the Patriot air-defense system and the Air Force AWACS early-waming radar aircraft. In the future, Dodgen speculated that unmanned aircraft such as the Air Force Global Hawk, will be added to the mix.

The Pentagon chartered a special agency to consolidate individual services' efforts to develop a single integrated air picture, known as SIAP. The connectivity to make the SIAP happen, said Dodgen, will most likely come from Link 16, a Defense Department data link that provides a tactical air picture. JTAMDO has conducted demonstrations with Link 16, but has not tested it in an operational environment he said. Currently, Link 16 offers the most promising communications technology, according to Dodgen. However, the system has yet to mature before it can become a mainstream technology, he said. "Only about 10 people at the Defense Department understand Link 16:" The Air Force plans to field 2,000 Link 16 radios during the next several years.

There are alternatives to Link 16, but Dodgen declined to endorse any specific technology. "If we figure out that we can't do it over Link 16, we'll have to find another data link, such as CEC." The Cooperative Engagement Capability, developed by the U.S. Navy, creates a composite tactical air picture with radar data from multiple Aegis ships. One problem with CEC, said Dodgen, is that it "needs more bandwidth." Nevertheless, he added, "we'll have a gateway between CEC and Link 16."

The SIAP office, he said, "will determine how far CEC will go." Ultimately, said Dodgen, it may be necessary to develop a new digital infrastructure, which the Pentagon labeled "joint composite tactical network" or JCTN.

The CEC prime contractor, Raytheon Co., has been advocating the notion of using CEC as the foundation for JCTN. Other companies, said Dodgen, also have pitched various concepts. "CEC is the most mature candidate. ... But there are other candidates," he said.

CEC has been proven to work in a carrier battle group. "But it's unclear that it can be expanded to a full family of systems in a theater," Dodgen said. "I think that there will be more cost-effective ways than CEC." Dodgen said he believes that many of the technical challenges in developing a single air picture for the military services could be overcome with commercial technologies. "My problems are going to be solved by the commercial industry," he said. Major airlines, for example, will be able to provide high-speed Internet services aboard jetliners. The same concept applies to the JCTN, he said.