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3
Commercial-Defense Synergy in Wireless Communications

Wireless communications technology development is a complex process that includes interactions between the commercial and military sectors. An understanding of these interactions, including the opportunities for and barriers to synergy, is crucial to an evaluation of the potential for expanded military use of commercial products. Building on the historical and technical foundation provided earlier in this report, this chapter identifies broader organizational and R&D issues that need to be addressed to ensure that the DOD fields affordable, state-of-the-art untethered communications systems that meet future military needs.

Wireless technologies are often transferred among government, industry, and academia. Such interactions take place through multiple mechanisms, sometimes in a continuing cycle from the commercial to the defense sector and back again (see Box 3-1). The synergy can evolve either during the initial research or after technologies are developed. For example, the DOD's funding of basic academic research on wireless technologies and networking (currently through the DARPA GloMo program) creates an active technology base for use in both military and commercial industries. Similarly, there is overlap within companies that have both commercial and defense divisions. Most large corporations also support academic research to gain access to important new concepts.

This chapter examines how this synergistic process might be leveraged to meet future military needs in untethered communications. Section 3.1 provides a brief overview of military use of commercial wireless products. Section 3.2 identifies the motivations and opportunities for



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Page 108 3 Commercial-Defense Synergy in Wireless Communications Wireless communications technology development is a complex process that includes interactions between the commercial and military sectors. An understanding of these interactions, including the opportunities for and barriers to synergy, is crucial to an evaluation of the potential for expanded military use of commercial products. Building on the historical and technical foundation provided earlier in this report, this chapter identifies broader organizational and R&D issues that need to be addressed to ensure that the DOD fields affordable, state-of-the-art untethered communications systems that meet future military needs. Wireless technologies are often transferred among government, industry, and academia. Such interactions take place through multiple mechanisms, sometimes in a continuing cycle from the commercial to the defense sector and back again (see Box 3-1). The synergy can evolve either during the initial research or after technologies are developed. For example, the DOD's funding of basic academic research on wireless technologies and networking (currently through the DARPA GloMo program) creates an active technology base for use in both military and commercial industries. Similarly, there is overlap within companies that have both commercial and defense divisions. Most large corporations also support academic research to gain access to important new concepts. This chapter examines how this synergistic process might be leveraged to meet future military needs in untethered communications. Section 3.1 provides a brief overview of military use of commercial wireless products. Section 3.2 identifies the motivations and opportunities for

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BOX 3-1 Handie-Talkies Serve Both Military and Commercial Needs In 1940 Motorola developed the first handheld two-way radio, the Handie-Talkie, a 2.3-kg AM unit with a range of 1.6 to 4.8 km. Within three weeks of U.S. entry into World War II, Handie-Talkie production exceeded 50 units a day; by 1945 more than 130,000 units had been built. In 1942 Motorola's design for the world's first portable FM two-way radio, the SCR-300 backpack unit, won a competition to replace an older Army Signal Corps radio, the "walkie-talkie." The SCR-300 weighed almost 16 kg, had an average range of 16 to 32 km, and could be tuned to various frequencies in the 40–48 MHz band. Motorola police radios were used in the Army's first radio relay system for behind-the-lines communications and its first radio teletype hookup. After the war, Motorola introduced the first commercially available portable radiophones, the Handie-Talkie radio line. A fully transistorized, VHF pocket transmitter version was developed in 1960. A fully transistorized, portable two-way radio was developed in 1962; its weight of approximately 1 kg was reduced by almost half in 1969. These devices have evolved into Motorola's current line of cellular telephones. Component technologies from commercial communications equipment are now designed into future generations of military equipment, thus furthering the ongoing cycle of commercial-defense synergy. commercial-defense synergy in the development of wireless technology. Section 3.3 outlines the barriers to synergy posed by mismatches between commercial capabilities and military needs and operating requirements. Section 3.4 examines three broad issues that need to be addressed in the design of future wireless systems for defense applications. Section 3.5 reviews the relevant defense technology policy issues. 3.1 Overview Myriad wireless technologies have originated within the government. Satellite programs initiated by the federal government in the early 1960s produced technologies that were quickly adopted for commercial use, starting with INTELSAT in 1965 in the United States and other countries in the 1970s. Another important government-initiated technology was packet switching, developed by DAPRA (then known as ARPA) in the late 1960s. This advance led to commercial and military packet-switched systems worldwide as well as to the Internet. The government also led the work on advanced coding techniques (for recovering data from deep-space probes), spread-spectrum techniques, signal and data encryption, and more recently on-board digital processing. All of these technologies have been adopted by commercial enterprises.1

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Page 110 Conversely, the U.S. military uses many commercial communications products. The military uses a variety of commercial systems, including satellites developed in the mid-1970s to transfer weather data to computer processing centers and disseminate the processed data; commercial satellites and land-based services to transport military-encrypted communications links; VSAT networks operating over commercial satellites to disseminate logistical and weather data; satellite video teleconferencing networks to provide training and distance learning to the National Guard and reserve units and for telemedicine applications; and access-management approaches such as TDMA. The ongoing synergy between the commercial and defense sectors is readily apparent in satellite communications. The introduction of commercial satellite communications in 1965 was limited to very small satellite payloads and required very large Earth stations to receive the very weak signals (e.g., INTELSAT Earth stations required antennas 100 feet in diameter). A 1971 experiment clearly demonstrated the feasibility of providing satellite communications—including digital voice, data, and fax services—to ships at sea. However, the business aspects of such services were not strong enough to justify the required investment in satellite and ground control systems. Subsequent events led to a contract between COMSAT, an international industry consortium, and the Navy to provide a GEO satellite system with an added commercial L-band package for ship-to-shore use. This agreement eventually led to INMARSAT, now widely used not only by large ships (e.g., tankers, cruise ships) but also by pleasure craft and mobile users around the world, who can transmit and receive data and voice via low-cost, brief-case-sized terminals. Terminals are also used on transoceanic airline routes for navigation, control, and passenger telephone calls. An INMARSAT spin-off, ICO, is building a MEO mobile telecommunications system using 12 satellites. Similarly, the introduction of commercial DBS sparked military interest in developing the GBS to satisfy broadband data requirements in all environments, including the battlefield, ships, and logistics. The architectures of Ka-band (superhigh frequency, or SHF), high-speed interactive systems planned for commercial operation by the year 2000 will have an impact on the ultimate GBS design in the near future. Ultrasmall-aperture terminals in these systems will be able to transmit several megabits per second and receive 100 Mbps from a 24-satellite constellation. The GBS has been designed to leverage the current DBS satellites through modifications such as moveable spot beams and different frequency bands. The opportunities for defense use of commercial off-the-shelf (COTS) products depend in part on the particular characteristics of a military

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Page 111 operation. For the purpose of analyzing communications requirements, military activities can be divided into the following four categories: • Non-mission-critical operations require general communications infrastructure to provide logistics, training, entertainment, and general administration. For these activities, the military has either purchased COTS systems or leased services operated over commercial carrier systems. For example, the Army Training and Doctrine Command uses a commercial teleconferencing system based on a VSAT to provide training to the National Guard as well as telemedicine services. • Limited peacekeeping missions, such as the Bosnia deployment, can feature a mix of COTS communications equipment (primarily VSATs and video teleconferencing) and military systems. • Regional conflicts, such as Desert Storm, can feature a mix of COTS and military systems depending on the threat to commercial assets. Conflicts of this type seem likely to benefit from the use of emerging COTS systems (or derivations) such as satellite-based personal communications and broadcast data satellites. • Strategic/global conflict requires the use of "survivable" military communications systems whatever the cost, implying reduced use of COTS systems. 3.2 Motivations For Commercial-Defense Synergy Two key factors currently motivate the DOD to seek commercial products and services. First, the size of the business and consumer markets and the nature of many commercial practices help achieve economies of scale at many levels. Second, commercial approaches to R&D reduce cycle time such that advances in technical performance can be integrated into field operations in a timely manner. The DOD therefore has both economic and functional reasons to adopt commercial products and approaches when they meet—or could be adapted to meet—defense communications requirements. The commercial equipment is likely to cost much less overall than would equivalent defense-unique systems. Furthermore, because commercial industry evolves very rapidly in response to a competitive marketplace, the DOD can leverage commercial developments to field equipment that offers advantages in size, weight, power, bandwidth, or performance much more rapidly than is possible using traditional defense procurement practices. Economies of scale are extremely important in the development and deployment of commercial products. Firms seek a balance of cost and quantity when deciding whether and how to enter business or consumer markets. As examples, business products such as VSATs are built in

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BOX 3-2 DirecTV Receivers: An Example of the Volume-Cost Relationship A DirecTV receiver consists of an 18-inch antenna and a sophisticated mechanism for receiving a 40-Mbps, digitally mutiplexed data stream. With more than 1 million units sold in the first year, these receivers are among the fastest-growing new product lines in the consumer electronics industry. DirecTV receivers were introduced at a list price of $700; after 2.5 million units were sold, the price dropped by nearly 50 percent because of competitive market pressures and economies of scale. Impressed by the capability of such a small receiver system, the Navy and other services determined that DirecTV technology could be adapted to meet the military's broadband transmission requirements. However, the quantity needed by the military—hundreds of terminals—is significantly smaller than the commercial market. If a DirecTV-like receiver were developed as a stand-alone military product, then the cost per unit might be hundreds of times higher than the commercial price because the development, tooling, and manufacturing-setup expenses would be amortized over a smaller production base and optimized for smaller production volumes. Three years after DirecTV was announced, the services were still working to define a military version. Had the features necessary to support military needs been considered before the product design was finalized, the DOD could have taken advantage of the cost reductions enabled by the market growth. volumes of thousands per month, and consumer products such as DirecTV (see Box 3-2) are manufactured in quantities of hundreds of thousands per month. The cost-quantity relationship forced the semiconductor industry, which originally evolved to support military and space applications, to switch to a commercial focus. As shown in Figure 3-1, the commercial market for semiconductors soared, whereas the defense share declined. In 1975 worldwide military purchases of semiconductors totaled $700 million, approximately 17 percent of the global market (INSTAT/SIA Information Services, 1997). At that time all major semiconductor manufacturers had military-quality product lines, particularly for high-reliability and extreme-temperature applications. By 1995 the military share of the market had dropped to less than 1 percent (INSTAT/SIA Information Services, 1997). Most major semiconductor manufacturers have announced the phasing out or termination of military product lines. Now military contractors must use either commercially available parts or obsolete, but military-quality, semiconductor parts. The commercial sector far outpaces the defense sector in production rates and volumes, not only for final products but also for subsystems and components. The largest DOD acquisition of communications equipment is the SINCGARS radio: The DOD has purchased 75,000 units over 10

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Page 113 image FIGURE 3-1 The world military share of the world semiconductor market dropped from 17 percent to 1 percent between 1975 and 1995 (the line graph, which corresponds to the scale on the right). During the same time period, the commercial market soared from $4.2 billion to $144 billion (the left bar graph for each decade) while the military market grew only slightly (the right bar graph for each decade). SOURCE: Joseph Neal, Commercial Plus Technology Operations, Motorola, Inc. Reproduced from Bradley (1996), with permission from the Semiconductor Industry Association and World Semiconductor Trade Statistics. years of production. In contrast, commercial production of land-based mobile radios is in the range of 400,000 units per month, and cellular radios are produced in volumes exceeding 2.5 million units per month for the largest suppliers. To meet such market demands a typical cellular telephone factory might produce 5,000 telephones a day. Another factor distinguishing the two sectors is the open, competitive environment of commercial production. The market pressure for improved quality, pricing, and other features is felt by all commercial competitors, whereas the defense market has typically been limited to a few and sometimes just one contractor. The next four subsections examine economies of scale manifested in several areas of commercial technology development: design, production, maintenance, and training. The fifth subsection reviews how cycle time can be reduced, thereby moving technical advances into the field quickly and also lowering costs over the life of a product. 3.2.1 Design Reuse Commercial communications equipment typically is produced with a basic design that has a 2- to 5-year life span. The components used in that design are selected in the 1 or 2 years just prior to product introduction and typically represent the then-current state of the art in performance and cost effectiveness. Thus, during the product life the components

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Page 114 remain cost-effective for the suppliers and are manufactured using state-of-the-art, cost-effective manufacturing facilities. Manufacturers typically anticipate new features in the market by modifying the design to use new components after 2 years of production. They also use components and manufacturing processes that are within a generation of the then-current state of the art, thereby operating close to the optimum level of cost effectiveness. By contrast, military equipment is often outdated: SINCGARS was designed more than 10 years ago, for example. Commercial firms achieve the initial economies of scale through design reuse. The use of previous hardware and software designs can often save 50 to 80 percent of development time because detailed design documentation can be readily reproduced and design weaknesses can be largely eliminated using experience as a guide. Although the design cycle is not a major contributor to the economic cost of a commercial product, it is typically a large part of defense deployment cost. The DOD typically does not reuse hardware designs, instead relying on independent "stovepipe" systems, which are optimized to solve a specific problem. Some efforts have been made to create software libraries for reuse. Increased reliance on common building blocks could significantly reduce design cycle time (see Section 3.2.5). 3.2.2 Production Learning Curve The learning curve is a statistical tool used to predict production costs and plan and control production. The curve is based on the assumption that there is a relationship between the time required to build a unit and the number of units that have been built; specifically, the learning process reduces the time needed to produce a unit as the cumulative number of units produced rises. It follows, then, that the less time it takes to build a unit, the lower the cost of that unit. If the cost of producing a unit follows an 80 percent learning curve, then there will be a 20 percent reduction in cost per unit each time the total number of units produced doubles. In the example shown in Figure 3-2, the first unit took 100 hours to build and the second unit took 80 hours, or 80 percent of the time and cost involved in building the first unit. The 10th unit required 48 hours, and the 20th unit required 80 percent of that effort, or 38 hours. The major factors that affect the cost of production are the initial cost, or the starting point of the curve, and the rate of improvement or learning, or the slope of the curve (Anderlohr, 1969). The implication of the learning curve is that large volumes of standardized items, produced continuously (i.e., without significant hiatuses), reduce the cost per unit. Heeding this message, commercial production is fairly continuous, fluctuating somewhat with the demands of the market

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Page 115 image FIGURE 3-2 As more units are produced, manufacturing costs per unit decline steadily. but generally changing processes gradually and with few interruptions. Although customized versions of products are increasingly in demand, the basic platform is usually consistent and the adaptations are minimal. By contrast, defense programs frequently begin with the building of only a few units, perhaps a few hundred, to determine feasibility or fulfill a limited need. Often these units are produced in numerous small batches with interruptions between the production cycles. Cost management is practiced throughout the design and production of commercial products. For example, production volume typically needs to be known before detailed designs can be completed. The component costs, labor costs, and investments in labor-saving manufacturing devices are factored into the final design of a consumer electronic device. Large production volumes enable the manufacturing of designs that would not be viable at smaller volumes. A significant example is the fabrication of customized ICs with many functions that normally would be implemented in separate ICs. The large volume reduces the overall cost of components, parts, and assembly, even after the nonrecurring investments are taken into account. Another example is the design of electronic equipment for cost-effective manufacturing. These designs typically feature modules that snap together and minimal numbers of wiring bundles, fasteners, moving parts, and different part types. Costs are reduced further through incremental production changes. During the repetitive commercial design and production cycles, the boundaries between system, subsystem, unit, and component begin to blur as automation enables larger and larger subsystems to be treated as components. In this way, what was once a high-technology system (e.g., computer memory) becomes a commodity part. Following the lead of the commercial sector, the DOD might achieve some economies of scale in production by revising its procurement practices

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Page 116 to make large-volume purchases of basic COTS communications equipment for entire departments at one time. Some isolated efforts have been made in this regard, but there are ample opportunities to expand this approach. 3.2.3 Maintenance and Logistics Support Economies of scale can be achieved in the maintenance of equipment after it has been developed and fielded. Equipment occasionally fails in the field because of design defects, manufacturing defects, worn-out mechanisms, lightning or power surges, or simply heavy use. Sometimes fielded equipment is upgraded during maintenance procedures to add new features or functions. In the commercial sector field-failure data are typically analyzed on highly automated equipment, which can trace failures to specific modules and components and automatically update design and component history databases, including any links to environmental factors. Design updates are inserted into the manufacturing process throughout the commercial life of a product, thereby improving its robustness. After approximately one year of production, experience with field failures often has produced the feedback necessary to eliminate most design defects, reduce manufacturing defects to a level consistent with the current state of the art, and generally achieve the best product possible within price constraints. Consumers rarely, if ever, pay for the maintenance or repair of low-cost communications equipment. Rather, warranties and service contracts are often viewed as a necessity in maintaining complex products that are not easily repaired; products are often replaced if they need repairs after the warranty expires. Viewing warranties as insurance policies, or guaranteed streams of income, specialty maintenance companies have emerged to provide a variety of maintenance tasks, both on site and at the factory. In the defense sector, communications equipment is often maintained by the acquiring agency rather than the manufacturer, typically at greater expense. Typically a module is replaced and the equipment is retested, a strategy that usually finds the primary defect but sometimes misses marginal problems elsewhere. Large numbers of spare components need to be kept available, either in replacement modules or in component form such that modules can be manufactured, throughout the useful service life of the system. The supply of spares is often threatened when, because of the small production volume, the supplier no longer finds the component profitable to produce. When this occurs the manufacturer usually notifies customers of an ''end-of-life buyout." The customers then try to

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Page 117 project future needs and purchase enough components to satisfy them (not always at competitive prices). The DOD is known for keeping communications equipment in service far beyond the life span of equivalent commercial technology; typically, military systems are removed from service only after catastrophic failure. Defense equipment is often kept in use for 20 years, whereas component suppliers often set product lifetimes at less than 8 years; thus, the military needs to stockpile approximately 10 years' worth of components. Under normal circumstances, the DOD assumes that 25 percent of its equipment will need to be refurbished at some point. The additional maintenance costs associated with traditional defense acquisition could be reduced if manufacturers—who can efficiently analyze all field failures, suggest redesign enhancements, and redesign components and modules to enhance cost effectiveness and other features—provided for maintenance and logistics support when appropriate. In addition, a reevaluation of military equipment maintenance practices may be warranted in light of the capabilities of advanced communications and transportation systems. Defense acquisition systems have historically provided logistics support for rapid equipment repair (i.e., within a few minutes of field failure) anywhere in the world by staging replacement modules near locations where critical equipment is in use. Such an approach may no longer be necessary. 3.2.4 Training The commercial sector achieves additional economies of scale in training. The expense of user, logistics, and support training is built into the cost of new product introductions, and training is subsequently converted from expensive formats (i.e., personal, face-to-face support) to videotape, interactive CD-ROM manuals, on-line help, and literature. By contrast, the training of defense maintenance and logistics support personnel offers few economies of scale. Training materials are developed, but they are neither as detailed nor as widely distributed as are commercial manuals. Indeed, defense support training can remain somewhat diffused and superficial because the military uses so many types of equipment and relatively small numbers of each type. As the DOD purchases more COTS products, the use of commercial training materials might be appropriate. 3.2.5 Cycle Time Commercial product design cycles, which usually last from one to four years, are set by competitive pressures: The first company to market a product with a new feature can reap large increases in market share and

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Page 118 profitability.2A new commercial communications product is released every few months. Manufacturers therefore begin to field test and optimize the features of products before the designs are completed, accelerating the development process by several years. This environment fosters the introduction of new and improved technologies at a very rapid pace, often at a low incremental cost to consumers. Companies gain additional reductions in cycle time by designing products to accommodate new features on each new production run, often every six months.
3These advanced commercial technologies are then available for rapid insertion into commercial or defense applications. The military product design cycle is much slower. It begins when a contract is awarded and ends with delivery of the final product, which is not field tested or optimized until the design is completed. The developer does not have sufficient control over systems integration, testing, and evaluation to perform concurrent engineering that would reduce overall cycle time. Further delays are imposed because training, logistics, marketing, and distribution processes are not generally developed concurrently with manufacturing tooling equipment as they are in commercial systems. A key design feature affecting cycle time is the ease of upgrading equipment. Commercial baseline products are designed to accommodate hardware and software extensions throughout the planned lifetime of the product. This is critical because of the high cost of the wireless infrastructure. The longevity of the infrastructure depends on a complex trade-off between the equipment offered by vendors and the pace of change in services. Typically service providers have a detailed road map that identifies when new services will be offered; these services are selected based on the equipment available at a reasonable cost and the market demand for a profitable service. Commercial upgrades to accommodate new services and changes in market direction are generally implemented through software updates rather than more-costly hardware changes. Therefore, software plays a growing role in product development and cycle-time planning. Software is also often used to correct hardware problems, such as designs that were oversimplified to meet a price point. In such cases new software requirements are discovered late in the product development cycle, meaning that software is the last element to be developed and may be installed either just before or even after production. Yet software updates need to be thoroughly tested and tolerant of all environmental and loading factors. As a result, the software development process is now of great interest. The quality and timely release of software as well as software-defined infrastructure services are therefore becoming critical factors in the commercial communications industry.

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Page 138 to support additional waveforms because of the costs involved, whereas the military would almost certainly pay for them to gain the added functional flexibility. 3.4.3.1 Software-Defined Radio Software radios are evolving in both the defense and commercial sectors. The military version is intended to enable interoperability among defense networks, reduce logistics support costs, and provide the capability to add new functions to fielded equipment through software updates.
19The commercial work is driven by the need to accommodate the large number of standards used in mobile telephony. The design of common hardware for a wide range of applications would offer convenience to consumers and simplify manufacturing; however, the ultimate popularity of these systems will depend on whether they prove to be cost competitive with multiple dedicated implementations. Several DOD-funded experimental models have been built. In field demonstrations, SpeakEASY was shown to be capable of receiving communications from the Air Force and translating them for the receivers and networks used by Army ground forces. The four-channel radio is compatible with some legacy waveforms and spans frequencies from 2 MHz to 2 GHz. The ACE, JCIT, and Millennium programs are not yet completed. Software radios are also being designed under the GloMo program to have adaptive interference-rejection capabilities. It is not yet clear whether any of these systems will offer the performance and cost effectiveness needed to initiate a production program. Most commercial dual-mode digital cellular and personal-communications units can implement multiple transmission and reception formats using DSP software. Information about commercial radios still in development is typically not publicly available. There are undoubtedly plans to make software radios, which will likely be less flexible than are military versions. The commercial radios may contain software that is not intended to be changed after manufacturing. Furthermore, they will likely not offer the frequency range, extent of waveform synthesis, or sophisticated security expected for military applications. Meanwhile, the commercial sector has focused intensive R&D efforts on various radio components to achieve incremental, practical advances. The DOD can expect to take advantage of the rapid commercial progress in many components—A/D converters, DSP chips, RF amplifiers, display elements, processors, batteries, and storage devices—which will probably drop in price over the next several years. However, as discussed in Chapter 2 (Section 2.4), the DOD will likely need to develop its own specialized filters that can accommodate a broad range of frequencies and bandwidths,

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Page 139 as well as antennas that offer both frequency and beam-shape agility. When all the functions of a radio are defined by software, the ''intelligence" and network services offered by the radio can be extended to greatly enhance military applications and perhaps eventually lead to intelligent radio services in commercial applications as well. Smart radios (i.e., radios capable of optimizing frequency, modulation, and protocols for a given purpose and signal environment) can incorporate the rules learned by an experienced communications specialist. Many simple rules define how to minimize interference. These rules can be applied in real-time, packet-based communications systems much more effectively than in traditional voice systems. Through real-time evaluation of each communication link and the spectrum in which the system operates, new levels of intelligence can be achieved to avoid jamming or to optimize transmissions under a wide variety of conditions (e.g., by minimizing battery drain, reducing traffic in the vicinity of hostile jamming activities, maximizing bandwidth or network capacity). The introduction of the multimode software radio creates a significant opportunity for the convergence of many different systems and functions. Traditional defense platforms have separate systems for communication, navigation, identification, data exchange, signals intelligence, electronic warfare, and other functions. A software radio could be rapidly configured to perform any of these functions in any combination required. This convergence of technology will reduce the numbers of military systems procured while also increasing the cost effectiveness and utility of equipment. The resulting lightweight, agile platforms will be capable of rapid response to support the small units of fast-moving military forces now evolving. The increased availability, utility, and power of radio devices will create a new paradigm for military communications (see Table 3-2). 3.4.3.2 Co-Site Interference Co-site interference, which is already a problem for military communications platforms, will worsen with the introduction of multimode, multiband radios unless new mitigation approaches are developed. Current technology designed to reduce the effects of co-site interference on radio performance is quite limited. Power combiners can connect up to five transmitters to a single antenna, but only if the frequencies are sufficiently separated. Receive co-site filters can suppress the carrier of colocated transmitters, but broadband signals are not suppressed adequately, and the broadband noise of transmit power amplifiers is not suppressed sufficiently at frequencies near the transmitting frequency.

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Page 140 TABLE 3-2 Current and Emerging Military Communications Paradigms Current Paradigm Emerging Paradigm Radios are a precious resource. Hardware developed decades ago remains in low-rate production with high unit cost. Radios are rationed to one or fewer per platoon. Radios are a ubiquitous resource. Like computing, communications will become so inexpensive that it will be widely available. As with computers, new radios are implemented as applications software running on standard platforms. Legacy radios. Radios are standardized but there are too many standards, all based on legacy hardware. Few radios are compatible with other radios even within the U.S. inventory. The problem is amplified when the Allied and multinational radio systems are considered. Interoperability. Radio waveforms, bandwidths, channels, modulations, error correction, and cryptography are all implemented in software. Even legacy systems are implemented in software, which might even be downloaded over the air. Manual mode and frequency selection. Radio operators select frequencies and modes based on command instructions. Radio units are often manually turned off (e.g., "radio silence") and communications cease. Connectivity. The radio decides which modulation, frequency, and power level is best based on "RF situation awareness" (the need to remain covert), the available resources, and the amount of data that need to be transmitted. Communications van complex. All the various radios need to be housed in large communications vans, which are scarce resources. "Palm top" communications complex. Multibands, multimodes, and multichannels are on a card; connectivity is achieved by "cleverness" and resource allocation, not brute-force transmit power and antennas. Radio as a communicator. Each radio has one channel for voice or messaging. Radio as a sensor. Each radio has many channels. Some can be programmed and used in networks for intelligence collection and emission location by triangulation. Development lead time. Radio upgrades and developments are measured in years. Rapid prototyping and deployment. New features and upgrades are implemented in software, with "few" hardware changes required. Individual radio units. Communication is point to point on a single link that is limited by output power, sensitivity, and waveform propagation. Communications network. The full set of protocols, including TCP/IP message routing, is implemented. Whole groups of units work together to achieve connectivity. Closed, proprietary architecture. Fully functional "black box." Open architecture. Standard interfaces and packaging are the norm, with plug-and-play hardware and software modules.

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Page 141 Moreover, receive co-site filters become complex when the number of co-site transmitters is three or more, and receiver noise performance is degraded, resulting in reduced transmission range and an increased error floor. Co-site problems extend to antenna beam shape, which changes when antennas are used in close proximity to each other or to metallic structures. Because of the unique conditions on military communications platforms, R&D in this area will likely need to be supported by the DOD. 3.5 Defense Technology Policy Issues The government influences private-sector technology development in a variety of ways. The instruments of government policy include indirect methods, such as investment tax credits, or direct methods such as federal funding for R&D and technology testbeds. Sometimes these policies are implemented to accelerate the development of strategically important technologies; at other times the motive is to ensure that equipment will be available for procurement by the government in a timely fashion. Government policies supporting the development of appropriate defense technologies have always been a special case. In the past, when defense requirements generally guided private-sector technology advances (e.g., transistorized components), federal investments in R&D were not controversial. Now that sophisticated consumer and industrial products are developed independent of defense requirements, the need for federal investments may seem less pressing. However, the DOD needs to maintain a competitive advantage over potential adversaries with respect to warfare capabilities, including communications systems. The technology policy issue for the future is how to encourage innovations in electronics and communications technology that will dominate world markets while also ensuring that the U.S. military retains capabilities that exceed those of potential adversaries. 3.5.1 Implications of Changes in Military Tactics The Gulf War demonstrated the way in which high technology permeates warfare. Advanced sensing, imaging, and targeting capabilities in the Patriot missile defense system, stealth aircraft, and other systems provided extensive advantages for U.S. forces. For example, Patriot missiles were aimed using surveillance satellites controlled from the United States. Liftoffs from Iraq were observed by these satellites within seconds, and critical targeting information was relayed through controllers in Colorado to the front-line Patriot batteries. This orchestrated activity demonstrated the capabilities of the U.S. military's existing global communications network, which required the support of high-bandwidth data links

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Page 142 to move sensor information both to and from the theater of action. But the Gulf War experience also suggests that communications advances are needed to enable rapid infrastructure deployment, logistics enhancements, and increased protection of technologies to prevent their exploitation by adversaries. 3.5.2 Rapid Infrastructure Deployment During the ground war, the mobile forces moved so quickly that the communications infrastructure could not keep up with the front lines. Future communications systems will likely need to be rapidly deployable (and redeployable) so that they can keep pace with rapidly developing battles. Because Iraq did not react when U.S. troops first began arriving in Saudi Arabia, the coalition forces were able to build up an overwhelming combat strength in the Middle East as well as the logistical stockpile needed to pursue vigorous modern warfare. Adversaries in future wars are unlikely to be so accommodating, meaning that forces will need to be projected rapidly from the U.S mainland. Future conflicts are likely to be "come as you are," and communications infrastructures will need to support immediate action. The recognition of this need has heightened interest in "instant infrastructures" based on satellite communications and mobile elements. The RAP has been proposed as a basis for a moveable front-line infrastructure with sophisticated, on-the-move antenna systems able to maintain high-bandwidth, point-to-point links with the rear-area infrastructure. To avoid the latencies inherent in satellite communications, hybrid systems that consist of DBS downlinks and UAV uplinks are being investigated. In general, these systems are viewed as backups to the terrestrial trunk linkages. Continued military R&D investments will probably be needed because there seems to be little commercial interest in moveable infrastructures. One example of a commercial system with moveable elements is the Metricom multihop packet radio network, which operates in the unlicensed ISM bands in the San Francisco Bay and Washington, D.C., metropolitan areas. Although the infrastructure radios are in fixed locations, the multihop architecture makes it possible to add coverage in an incremental fashion through the addition of relay radios within the service area; bandwidth can be added also. 3.5.3 Logistics Future military communications systems will need new features corresponding to the reduced size of U.S. forces. Current planning provides

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Page 143 forces that are only sufficient to fight two regional conflicts at the same time. Instead of stationing so many troops overseas in areas of high tension, a split-base approach will be used, with advanced echelons overseas and the bulk of the forces on the U.S mainland. This approach will require high-quality, high-bandwidth connectivity worldwide, complete with access extensions that can be rapidly deployed, torn down, and reestablished as troops move. Logistics tracking and management will be especially critical, given the growing need to transport materiel from the United States to the scene of the conflict. Many commercial systems are available. For example, OmniTRACS makes it possible to track vehicles continuously as they move and to plan routes efficiently. Package delivery services such as UPS and Federal Express have deployed sophisticated logistics systems for tagging packages and tracking them en route while also providing user-friendly on-line services that enable shippers to find their shipments. Wireless LANs were originally developed partly for warehousing applications. Finally, wireless tagging technology could provide the DOD with automatic inventory and location-identification capabilities, providing the basis for a complete logistical information system that could track the location of every item shipped. 3.5.4 Preparing for Unsophisticated Adversaries There is some uncertainty about the technical requirements for communications during future confrontations with unsophisticated adversaries. Recent U.S. actions in Haiti and Somalia are examples of these types of operations, which may become more common as the United States plays an expanding role in peacekeeping and peacemaking missions. These countries tend to have little modern communications infrastructure, although this situation is changing as worldwide markets evolve for advanced technology. When deployed in less-developed countries, the U.S. military could bring along state-of-the-art commercial infrastructure technology. These systems would need to be shipped, installed, and operational within days, with military systems sufficing in the meantime. The commercial systems could transport the bulk of noncritical traffic, making it accessible to a smaller number of military-specific systems in the field. In many ways, peacekeeping and other nontraditional military operations are similar to law enforcement activities, and many of the same communications issues need to be addressed. Even an unsophisticated adversary could disrupt service to U.S. forces using commercial systems. For example, cellular infrastructure is difficult to hide and could easily be targeted for sabotage. Although stealth and LPD are not always critical to defense communications, steps need to be taken to prevent adversaries

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Page 144 from learning of upcoming operations, performing traffic analyses, and intercepting specific types of communications traffic. The basic security and authentication mechanisms in the latest commercial systems can reduce interception by the technically unsophisticated; they are sufficient for nontactical communications traffic such as logistics support. Military-specific systems will continue to be needed for transmissions that require complete security. The DOD might need cooperation and technical information from U.S. or foreign manufacturers so as to monitor the traffic of adversaries, track specific telephones, or infiltrate existing communications systems in particular countries. The U.S. military therefore needs to maintain a technical awareness of foreign-made equipment, perhaps as part of the effort to demonstrate, test, and procure COTS wireless technology (see Sections 3.2 and 3.3). 3.5.5 Preparing for Sophisticated Adversaries Sophisticated communications technology is rapidly becoming a commodity. During the Gulf War some military specifications and procurement procedures were abandoned in an effort to get new capabilities, such as GPS, into the hands of the troops. Any adversary could buy the same sophisticated technologies; the threat is measured by how much the adversary can afford. Indeed, one of the implications of the Gulf War as a model for future conflicts is that the United States might not prepare sufficiently to recognize or defend against sophisticated adversaries. A sophisticated adversary can be defined as one with the technical capability to build advanced communications systems or the financial resources to purchase what it needs on the global arms market. The greatest immediate threats are countries that can buy technologies from the countries that make them; for instance, the SCUD missiles used by Iraq in the Gulf War were based on the Chinese Silkworm missile. To maintain a competitive advantage against these adversaries, the U.S. military could add military-specific modifications, such as security or waveform hiding, on top of commercial core systems. The military can leverage many commercial technologies, among them advanced ICs, DSP chips, and protocols. The advantage gained will depend on how these capabilities are integrated into defense systems and the choice and performance of the added military-specific capabilities. 3.6 Summary The DOD has many reasons to use commercial communications products and practices whenever possible, building on a long tradition of

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Page 145 synergy between the two sectors. Many COTS technologies offer cost and performance advantages, and their quality is better than ever. The economies of scale achieved in mass production provide additional benefits and lessons that can also be exploited by the military. The selective use of commercial products and practices in DOD systems could help accommodate growing needs for global, untethered communications systems in spite of declining defense budgets. However, the military will continue to have some unique needs that cannot be met by consumer products, or even future commercial R&D programs, because the motivations and interests of the two sectors differ. The DOD has unusual needs in three fundamental areas: network architecture, which influences all other aspects of a communications system; security, which encompasses confidentiality, data and system integrity, and service availability; and multimode, multiband systems, which can enable interoperability among diverse systems. The DOD needs to examine its needs in these areas carefully and probably pursue its own R&D in selected technology areas. All of these issues are addressed further in Chapter 4. Notes 1. For example, advanced coding (Cacciamani, 1970, 1971, 1973) has been used in commercial satellite communications since the early 1970s for both data and highly compressed digital imaging, enabling the use of antennas on the order of 18 inches in diameter for digitally compressed video signals with link BERs less than 10-9. The best known of these technologies is probably CDMA, which has been widely adopted for cellular and personal communications systems worldwide. Encryption, along with data mining and RF fingerprinting, is increasingly being used to protect against fraudulent use in cellular systems, video entertainment subscription receivers, and business data. Finally, on-board digital processing will be used in the planned mobile telecommunications satellite and high-speed data satellites such as Teledesic. 2. A short lead time in a growing market can result in a large increase in market share. In addition, because prices can fall quickly after a new product is introduced, the first to market is often the only competitor to make a substantial profit. Yet a release date is often difficult to predict. Companies can be punished by the market if they fail to meet predicted release dates, as often happens, for example, with software upgrades. 3. The internal design cycle may actually be much longer because the basic equipment architecture is more likely to be on a two-year design cycle paced by the evolution of new semiconductor components. During the baseline design cycle of up to four years, anywhere from one to four design teams may be working on the next baseline architecture. 4. Many U.S. commercial wireless communications suppliers include divisions that have historically been involved in defense work. Within these companies,

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Page 146 cross-fertilization between the defense-related and commercial units may provide a mechanism for meeting military surge needs using the company's commercial products. However, this type of crossover is not always straightforward because of the differences between defense and commercial markets. 5. For example, current regulations regarding processors, A/D converters, and cryptography appear to reflect technologies that are nearly a decade old. The advent of common high-performance microprocessors enables the widespread development and use of cryptographic algorithms, which are often distributed on the Internet. The export of A/D converters is limited to technology of less than 8 bits, but advanced sigma-delta technology has only 1 bit (noise shaping and DSP techniques are used to increase dynamic range). Thus, the number of bits no longer seems like a useful metric for A/D converters; the metrics used to evaluate microprocessors seem equally outdated. 6. This is a simplified description of the decision-making process. More precisely, throughout the design, fabrication, and deployment of commercial products, trade-offs are made among performance requirements, standards requirements, cost goals, and design approaches to define a product that would be the most attractive and competitive in the marketplace. International, national, and regional standards determine many commercial design parameters, including off-axis emission from an antenna, maximum power flux radiated to Earth from a satellite, the capability of system users to coordinate or coexist with other users of a frequency band in the same geographic location, and numerous electrical safety regulations (e.g., related to wiring, batteries, radiation hazards, and chemical exposure). 7. Customers understand and expect this and are generally not willing to pay for a capacity that sits idle most of the time. Even during the busiest hour of the average business day—conditions that the systems are engineered to handle—there is a measurable probability of blockage that is calculated based on customer willingness to pay. Because the cost of a blocked call is usually only the effort required to try again shortly, there is little incentive to reduce the probability of blockage to zero. An interesting demonstration of the customer's acceptance of blockage and delay is the phenomenal growth of the Internet, where service is provided on a best-effort rather than guaranteed basis (although data services continue to come under increasing pressure for better service access). 8. Intel Corp., which after marketing its Pentium microprocessor found a design flaw in the precision of certain mathematical operations, uses a test suite comprising of billions of instructions to validate each possible instruction, register, arithmetic function, interrupt process, and instruction trap as well as sequences of events to prevent any surprises in complex applications. Only now are academic researchers considering more sophisticated theoretical techniques for dealing with testing processes of such enormous complexity. This research is critical to the future success of complex systems. 9. For example, commercial processes might take place at temperatures ranging from 0 to 50 degrees Celsius (°C) rather than -55 to 125 °C as in military processes. Or, commercial processes might involve 30 G of force rather than 1,000 G. 10. The NES is an encryption system certified by the National Security Agency

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Page 147 that enables clusters of defense computer networks to interconnect through the unclassified Internet. The NES provides high levels of assurance that a system communicates only with other systems that have comparable security levels. 11. Several military initiatives, including the Multilevel Information Systems Security Initiative and the DOD Goal Security Architecture, are intended to deal with various aspects of infrastructure in an effort to enable interoperability among systems. However, these programs have yet to field functions that enable communication between independent defense networks. 12. The ACN is designed to provide hierarchical communications over a broad theater of operations. Cross-linking and networking will enable various networks to communicate and access services through satellite links worldwide. The ACN will also serve as a repeater, picking up signals and rebroadcasting them over and around terrain obstacles, thereby extending the range of low-power equipment used on the ground. 13. In a base-station-oriented architecture, a greater investment is ordinarily made in the base station than in terminals. In such a network, both the transmit and receive link equations can benefit from the improved performance of larger antennas, more powerful transmitters, and more sensitive receivers. In typical systems the link advantage relative to the peer-to-peer design is approximately 10 dB. 14. Security is an issue in equipment deployment: The use of systems with cryptographic security requires procedures for securing clearances and equipment controls. 15. The TCP/IP protocol suite would need to be supported on top of ATM because the DOD has identified TCP/IP as the means for ensuring interoperability across heterogeneous military networks and because the entire system is unlikely to be constructed from native ATM technology. 16. An additional drawback is ATM's strong connection orientation, which makes it difficult to support mobility because existing connections need to be broken and reconstructed repeatedly. Furthermore, the ATM cell (i.e., data packet) structure was designed for the extremely low BERs of fiber-optic communications, whereas a radio fade can persist for several cell durations, making it difficult to use standard coding techniques to improve link quality. The loss of even a small number of ATM cells in a highly stressed network can dramatically reduce packet throughput. 17. The importance of distilling source information prior to transmission over a network is well understood in the commercial sector but remains an issue for the military, especially the Army, where communications, command-and-control, and intelligence functions are separate. There is no financial incentive on the part of the command-and-control and intelligence communities to spend resources to distill data at the source. Often the problem is passed off to the communications community, which is forced to transmit whatever is provided. For example, in situation awareness (SA) reports, positions are reported every 12 seconds regardless of motion. As a result the communications system is overloaded with SA reports. A more efficient approach would be to project positions based on direction and velocity and only send reports when the trajectory or velocity changes. But such an approach would require the development of software at a cost to the command-and-control

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Page 148 community. Instead the practice has been to blame the communications system for failing to support the traffic load. This situation would never arise in the commercial cellular industry, where providers take a systems approach and make trade-offs between bandwidth costs and source compression costs. 18. Mobile code, such as Java, might eliminate the need to agree on a compression standard because the delivery of executable code (along with the transmitted data) would allow the receiver to adapt to the sender's coding scheme. 19. An alternative approach would be to implement new functions in ASIC chips, which offer efficiencies in terms of power consumption. However, this approach would not provide an open architecture and might not be adaptable to future radio waveforms.