MILITARY AVIONICS TWENTY YEARS IN THE FUTURE

This paper explores the generic structure of avionics beyond the Pave Pace system architecture. Projected constraints, opportunities and trends in several pervasive system building blocks which should be mature by this time frame are discussed and an example of the form this architecture might take is offered. In developing these projections, the author interviewed several technology experts in Industry and Government to help in forecasting the future of military avionics. General conclusions are: (1) costdriven sensor solutions will drive the avionics designs for most military avionics applications in order to meet demanding situation awareness goals, (2) the most pervasive and highest-leveraged building blocks used to build this advanced system will be commerciallyavailable data and signal processors along with advanced A/D converters and digital and RF photonics, (3) a continued increase in time sharing and physical integration at every level of the avionics architecture is projected, including multifunction EO and RF apertures, RF support electronics and a highly integrated digital system, (4) distributed high-speed photonic switches will permeate the architecture to achieve a unified interconnect network across RF, IF, data and signal processing modules built from families of printed wiring boards, (5) advances in packaging and microelectronics will result in the need for liquid immersion cooling and 3-dimensional stacking of RF, digital and photonic circuitry to support integrated apertures, digital receivers and data and signal processors to accomodate the needed speed and functional integration, (6) the digital boundary will move closer to the apertures to enable IF digital receivers for electronic warfare and radar applications (digital receivers up through L-band will have occurred during the Pave Pace era) and will extend the use of photonics beyond the digital arena to where photonically-controlled beam steering for phased arrays, RF signal distribution and hetereodyning will be possible. INTRODUCTION Predicting the characteristics of the next military avionics system beyond Pave Pace, which is not yet demonstrated, is obviously difficult because many assumptions must be made about the future direction of military priorities, budgetary constraints and the degree of success researchers will have in maturing several key technologies. This paper assumes the drive for low cost avionics will continue and that the 20 year system will evolve from the Pave Pace system introduced around the 200710 time frame. Therefore, one of the tasks at hand is to identify pervasive, highly-leveraged building block technologies, unavailable to the Pave Pace system that can further reduce avionics costs. For the 20 year design, these technologies should be in the early stages of prototype device development and significant funding interest must be shown by DoD departments such as the Advanced Research Projects Agency (ARPA). FUTURE AVIONICS NEEDS In the author’s opinion, the greatest challenge facing future military avionics is to contain costs while providing the sensor and processing capability that will enable situation awareness and survivability against mobile threats in a system configuration which is ultra-reliable and supportable for austere base operation. The flyaway costs of fighter avionics (measured as a percentage of weapon system flyaway cost and exclusive of software costs) has increased steadily since the 1960s from about 12% for the F-4 to almost 40% today. Looking at cost, weight, volume, failure rates and electrical power requirements for advanced fighter avionics, Pave Pace studies showed that almost 60% of the values of these parameters could be attributed to RF sensors while about 20 % of “the problem” is attributed to processing and its associated networks (the remaining 20% being the electronic portion of stores management, vehicle management and controls and displays).