Conformal Antennas Miniaturized through Magneto-Dielectric Materials

RT&L FOCUS AREA(S): General Warfighting Requirements TECHNOLOGY AREA(S): Air Platforms; Battlespace Environments; Electronics OBJECTIVE: Demonstrate printed-microstrip antenna size reduction through substrate permeability for improved size, weight, and power (SWaP), bandwidth performance, phased array architecture, improved low observability and probability of detection characteristics. DESCRIPTION: The limits of microstrip antenna miniaturization are reached as permittivity values approach low double digits; at which point the antenna becomes too inefficient a radiator for practical use in an airborne communication system. Appreciable reductions in microstrip antenna size can be gained through an increase in the permeability of the printed antenna's substrate [Refs 1, 3, 5, 6]. When compared to traditional permittivity (only) increases, a combination of standard permittivity increases with novel permeability increases could result in comparable size reduction and better Radio Frequency (RF) performance [Refs 1, 3, 6]. The permittivity of printed antenna substrates is often increased to decrease antenna size, sacrificing antenna efficiency resulting in poorer RF performance and heat generation [Refs 2, 4, 6]. Permeability can also be increased to reduce size while counterbalancing the effect of permittivity increases on the antenna's characteristic impedance, resulting in a better performing, more efficient, miniaturized antenna that operates over a wider bandwidth [Refs 1, 3, 6]. Smaller conformal printed antennas can be integrated while minimizing impact to the aerodynamic characteristics of the hosting aircraft. Smaller antennas that have undergone a 50% reduction in size due to magnetic properties are sought. In addition, miniaturized conformal antennas can be integrated while minimizing negative impacts to the Radar Cross Section of an aircraft, when compared to common antennas. Aircraft with smaller conformal antennas operating from the Aircraft Carrier (Nuclear Propulsion) (CVN) could potentially have better Low Observable/Low Probability of Detection (LO/LPD) profiles than their standard counterparts, decreasing the likelihood of CVN detection. PHASE I: Develop an initial conceptual design for a conformal microstrip patch antenna that has been reduced in size by 50% solely as a result of the substrate material's electromagnetic permeability characteristics while minimizing loss so that loss is comparable with practical printed antennas miniaturized through other means. Perform modeling and simulation in order to provide a conceptual design trade study for the antenna and its substrate. The Phase I Option period, if exercised, must include developing an initial antenna design that includes a plan for substrate fabrication, antenna feed design, and anticipated prototype antenna fabrication cost. Any microstrip antenna shape can be considered, as well as any permittivity characteristic for the substrate as long as a 50% reduction in size due to magnetic properties can be demonstrated. The design must also demonstrate improved antenna efficiency and frequency bandwidth for the prototype antenna over traditional antennas of equivalent size that have been miniaturized solely through increased permittivity. The Phase I effort must design, develop, and deliver a model of the antenna radiation pattern, impedance, efficiency, and explanation of antenna miniaturization attributes. The Phase I effort must include prototype plans to be developed under Phase II. PHASE II: Develop a prototype based on the Phase I design. Test antenna prototype to validate maturity and expected/modeled performance. Characterize initial prototype's performance, identify any deviations from modeled performance and cause(s) for deviation, and produce improved design to address deviations and deficiencies. The Phase II Option period, if exercised, must produce an improved prototype; it must characterize improved prototype's performance; and identify any deviations from expected performance and cause(s) for deviation. PHASE III DUAL USE APPLICATIONS: Complete development of the miniaturized antenna, demonstrate performance in an operationally relevant environment. Miniaturized conformal antennas would find use on any commercial aircraft or space vehicle desiring to save weight while achieving the same or better communication system performance experienced with legacy antenna options. REFERENCES: Hansen, R.C. and Burke, M. Antennas with magneto-dielectrics. 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