3.6 RF Components

3.6.1 Warfighter Needs

Radar remains DoD's primary all-weather sensor to provide capabilities such as surveillance, situation awareness, self and area defense, targeting, and battle damage assessment. In addition, a major compliment to the hardkill capability or weapons is the softkill afforded by EW systems which can potentially handle a much larger attack force than hardkill weapons. Finally, the glue that holds all these capabilities together to form an effective warfighting force is the communications networks. These three areas rely heavily on and are enabled by RF technology which represents the key to force multiplication (the ability of a minimum number of U.S. platforms and personnel to defeat a much larger enemy force), and the avoidance of technological surprise on the battlefield. The following Joint War Fighter S&T areas are supported: Dominant Battlespace Knowledge, Information Warfare, Precision Force, Combat Identification, Electronic Warfare, Joint Theater Missile Defense, Military Operations in Urban Terrain, Joint Countermine, and Joint Readiness. The availability of affordable, manufacturable RF electronic components which satisfy the performance, weight, size, interoperability, cooling, and maintainability requirements of military systems is vital for sustaining the competitive edge of U.S. forces over their adversaries. These warfighting capabilities require reductions in size, weight, volume, power consumption and costs. Advanced high performance and affordable RF MMIC technology is currently being transitioned into a broad range of military systems, including the F-15/ALQ-135, LANTIRN, AMRAAM, MILSTAR, GEN-X, GBR, LONGBOW, SADARM, STAFF, and F-22 radar and EW arrays.

3.6.2 RF Components Overview

3.6.2.1 Goals and Timeframes. The RF Components thrust involves the technology required to generate, control, radiate, receive and process VHF, UHF, microwave, and millimeter wave power. The technologies under development are applicable to: solid state and vacuum electronic devices, low noise and signal control components, microwave power modules (MPMs), monolithic microwave integrated circuits (MMICs), transmit/receive (T/R) modules, advanced packaging and interconnect technology, antennas, and frequency control devices. The four technology efforts that comprise the RF Component Subarea are Solid State, Vacuum Electronics, Antenna Support, and Frequency Control. The results of these efforts enable many of the goals in Radar (3.1), Communications and Electronic Warfare.

3.6.2.2 Major Technical Challenges. A particularly challenging technical obstacle confronting military systems is that of producing affordable solid state amplifiers for broadband microwave and millimeter wave applications that simultaneously achieve high output power, high efficiency, small volume and acceptable linearity. Specifically, amplifiers meeting these objectives must be produced that have instantaneous bandwidths extending over frequency ranges from 1 to 18 GHz, 18 to 40 GHz, 40 to 75 GHz, 75 to 110 GHz, and 110 to 140 GHz, at costs ranging from one-fifth to one-tenth that which can be achieved using present design approaches and manufacturing capabilities. The following projects are being undertaken in order to address these deficiencies: (1) intensive effort is continuing at the inter-chip level to develop improved, more compact packaging and interconnect technology, and at the intra-chip level to increase the level of IC integration; (2) in the frequency control sub-area, a project has been planned to achieve a 100x reduction in oscillator acceleration sensitivity; (3) to achieve greater (10x) clock accuracy with lower power requirements, new (quartz-like) piezoelectric materials, such as langasite and lithium tetraborate, and novel resonator structures are being explored; and (4) to realize multiple-function, reconfigurable antenna arrays, work is in progress to identify and realize viable approaches for reconfiguring apertures so that they can perform multiple functions and provide failure correction.

3.6.2.3 Related Federal and Private Sector Efforts. Related efforts include metrology work with DOC/NIST and joint programs with NASA in solid state and vacuum electronics.

3.6.3 S&T Investment Strategy

3.6.3.1 Technology Demonstrations. None

3.6.3.2 Technology Development. Particular emphasis is being placed upon the development of Integrated CAD (Solid State and Vacuum Electronics); High Density Packaging; Wideband, High Power, Highly Efficient Vacuum Tube and Solid State Amplifiers; Mixed Signal ICs; Materials for Frequency Control; MMW Integrated Circuits; and Compact Multifunction Antennas.

3.6.3.2.1 Compact High Power RF Transmitters. This development addresses DTO SE.19.01.NF. The main objective is the Microwave Power Module (MPM) technology development and to facilitate the transition and insertion of MPMs into a wide range of radar, electronic warfare and military communications systems. Specifically, the effort seeks to demonstrate: single-device and linear (1xn) arrays of 6-18 GHz, 50-to-100-watt MPMs for EW transmitters; 250 watt, 8-18 GHz MPMs for standoff jammer systems in which multiple threat signals are simultaneously processed; 125 watt, 4-6 GHz MPMs for communications applications with efficiencies greater than 40%; and 50 watt, 18-40 GHz MPMs for EW, radar, and communications applications.

3.6.3.2.2 Affordable Multi-Chip Modules for Phased Array Antennas. The DTO SE.20.01.FE seeks to develop high density microwave and millimeter wave packaging and interconnect technologies for shallow depth/conformal phased array antennas used in radar, EW, Smart Weapons and communications technology. Goals include: 5:1 volume reduction; 10:1 cost reduction; and 2.1:1 weight reduction.

3.6.3.2.3 Low Power Consumption RF Electronics. DTO SE.21.01.FE is developing affordable, low power consumption RF electronics for military man-portable communications and for airborne/space platforms that are volume and weight starved. This effort addresses the full spectrum of components and devices for these applications.

3.6.3.3 Basic Research. Basic research in the RF Component technology area is directed toward the synthesis of advanced semiconductor, superconductor, and ferrite materials, and the development of affordable processing sequences for them. The successful completion of research tasks in these areas will enable development of high performance, reliable, low-cost structures for RF devices and components used in DoD systems. Basic research efforts provide technology options for device and component designers and fabricators that may lead to the realization of improved or entirely new classes of devices and components. Specific device/component-related goals that motivate these efforts are: achievement of improved device performance (e.g., higher frequency, higher temperature operation, high efficiency, lower noise, reduced complexity, and ability to support small feature sizes), lower cost, higher yield, improved predictability of properties, and greater reliability.