Multi-Octave, High Power Efficiency Active Electronically Scanned Array (AESA)
Navy SBIR 2020.1 - Topic N201-012
NAVAIR - Ms. Donna Attick - email@example.com
Opens: January 14, 2020 - Closes: February 12, 2020 (8:00 PM ET)
AREA(S): Air Platform, Electronics, Ground/Sea Vehicles
PROGRAM: NAE Chief Technology Office
within this topic is restricted under the International Traffic in Arms
Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import
of defense-related material and services, including export of sensitive
technical data, or the Export Administration Regulation (EAR), 15 CFR Parts
730-774, which controls dual use items. Offerors must disclose any proposed use
of foreign nationals (FNs), their country(ies) of origin, the type of visa or
work permit possessed, and the statement of work (SOW) tasks intended for
accomplishment by the FN(s) in accordance with section 3.5 of the Announcement.
Offerors are advised foreign nationals proposed to perform on this topic may be
restricted due to the technical data under US Export Control Laws.
Develop electronically steerable radio frequency (RF) transmitters over
multi-octave bandwidth yet with optimum power efficiency to achieve
simultaneous multi-octave bandwidth high-efficiency performance.
Electronically steerable RF transmitters are highly demanded in battlefield
communication and electronic warfare systems. Traditional approaches are mostly
based on phased arrays in which phase shifters are used to steer the antenna
beam and power amplifiers are used to provide the transmitted power. Such
architectures, however, suffer in several aspects when multi-octave operations
are needed. The grating lobes of antenna array may appear at the higher end of
the operating band and destroy the aperture efficiency while the mutual coupling
between the antenna elements in the lower end of the band may negatively affect
the antenna to transmitter impedance match and thus the radiation efficiency.
On the other hand, the trade-off between bandwidth and efficiency in any RF
transmitter often must be made according to the famous Bode-Fano limit, which
indicates that a good impedance match to a high-Q load cannot be achieved over
a wide bandwidth. For this reason, multi-octave RF power amplifiers (PA) are
usually not efficient as the existence of transistor parasitics limits the
impedance match bandwidth unless a sub-optimal impedance matching condition is
used. Similarly, in antenna systems, the form factor constraints often require
high-Q, narrow band antenna elements rather than broadband antennas.
Multi-octave impedance match to a single antenna is usually impossible. A
conventional Ultra-Wide Band (UWB), electronically steerable RF transmitter can
thus not be efficient for the above reasons, which in turn limits its maximum
operating power for a fixed design of heat dissipation. Tunable components that
may tune the matching between antenna and power amplifier to adapt to its
operating frequency have been proposed. These components are mostly in the form
of switches or variable capacitors made of microelectromechanical systems
(MEMS) or phase change material, which may suffer limited power handling and
add additional power loss caused by the tuning mechanisms.
Design, develop, and demonstrate an efficient transmitter and antenna array
architecture that allows efficient transmission of RF signal with more than 40
dBm power and with the overall system power efficiencies over 50% from 2GHz to
at least 4GHz, preferably 8GHz, while being electronically steerable over at
least +/-45 degrees. Identification of the appropriate electronics technologies
and antenna design must be made during this phase, with feasibility
demonstrated through simulation results. The Phase I effort will include
prototype plans to be developed under Phase II.
Further develop and perform hardware demonstration of the Phase I concept and
the predicted performance in a small scale, with aperture size equivalent to
four to eight element phased array. Ensure that the minimum antenna gain will
be no less than the ideal aperture gain by 3dB. Prepare the metrics of
evaluation that include a chart of power efficiency as a function of both
frequency and scanning angle.
DUAL USE APPLICATIONS: Integrate Phase II designs to test installed on an
aircraft platform with a goal of maintaining RF performance from Phase II in an
installed aircraft environment. Successful technology development would benefit
airborne- and ground-based radar systems, aviation, and large communication base
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3. Song, Y.,
Zhu, R. and Wang, Y.E. "A Pulsed Mode (PLM) Power Amplifier with 3-Level
Envelope Delta-Sigma Modulation (EDSM)." 2015 IEEE Topical Conference on
Power Amplifiers for Wireless and Radio Applications (PAWR): San Diego, CA,
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Xu, Q. and Wang, Y.E. "Nonreciprocal Components with Distributedly
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Techniques, Vol. 62, No. 10, October 2014, pp. 2260-2272. https://ieeexplore.ieee.org/document/6887369
High-Bandwidth; High-Efficiency Antenna Array; Multi-Octave Transmitter;
Integrated Antenna Array With Power Amplifiers