TECHNOLOGY AREAS: Sensors
OBJECTIVE: Develop and demonstrate approaches for realizing metamaterial-based micro-electromechanical (MEM) ultra-low-loss non-dispersive phased-array antennas for multifunction radar and communication systems in unmanned and micro air vehicles.
DESCRIPTION: Phased-array multi-function radar and communication systems are ideal for unmanned and micro air vehicles that possess challenging requirements for size, weight, power consumption and cost. Whether a radar or communication system can meet such challenging requirements is critically dependent on the design of not only the antenna, but also key components such as phase shifters and transmit/receive electronics that are required to drive individual antenna elements. For example, recent advances in the integration of slow-wave structures with MEM switches have resulted ,  in low-loss broadband-matched phase shifters, which will allow them to be integrated with the antenna  and driven by a few transmit/receive electronic modules, thereby reducing the size, weight, power and cost of the system. In addition, by taking advantage of combining the different dispersion characteristics of metamaterials and natural materials, non-dispersive phase shifters with a constant phase across a wide range of frequencies can be designed , which will greatly simplify the operation of frequency-agile and broadband-modulated multifunction radar and communication systems. To demonstrate the potential of the above-mentioned improvement in phased-array antennas, this project is divided into distinct phases as described in the following.
Both Phase I and Phase II should be conducted with a focus on not only performance improvement, but also robustness, reliability, manufacturability, yield, qualification and technology transition for deployment in unmanned and micro air vehicles. Costs of a transition/qualification effort should be estimated as part of the Phase II work package, and a potential transition strategy should be discussed in basic detail during Phase I and in finer detail during Phase II.
PHASE I: Phase I should focus on the design and evaluation of a metamaterial-based MEM Ka-band phase-shifter unit cell. The unit cell should be capable of uniform performance between 24.5 and 27 GHz with a phase shift of 45+/-5 degree, an insertion loss <1 dB, a return loss >20 dB, a switching speed < 5 us, and a power consumption < 10 uW.
PHASE II: The first half of Phase II should focus on the design, fabrication and demonstration of 4-bit Ka-band phase shifters with uniform performance between 24.5 and 27 GHz, a phase resolution of 22.5 deg from 0 deg to 337.5 deg, a phase ripple of less than +/-5 deg, an insertion loss < 2 dB, a return loss >20 dB, a switching speed < 5 us, and a power consumption <10 uW. The size of the phase shifter should be smaller than 5 mm x 5 mm x1 mm.
PHASE III DUAL USE COMMERCIALIZATION:
Military Application: The array should be applicable to all military radar and communication systems for which size, weight, power and cost are critical. With low RF loss and DC power, it can be readily stacked to form a two-dimensional array with only air cooling.
Commercial Application: The ultra-low-loss non-dispersive phased-array antenna should be equally applicable to commercial communications, such as satellite communications and wireless communications with multiple-input-multiple-output (MIMO) antennas.