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Compound Reconfigurable Dual-band Solid State Power Amplifier using a Single GaN HEMT for S and X-band Operations

Waldstein, Seth William
http://orcid.org/0000-0002-4528-9990
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563874650458585

Abstract Details

2019, PhD, University of Cincinnati, Engineering and Applied Science: Electrical Engineering.
Currently, NASA has the FCC assigned frequency ranges for Near Earth Network satellite communications at S-band (2.2-2.4 GHz) and X-band (8.0-8.5 GHz). Sharing of this capacity to alleviate overcrowding has allowed NASA commercial flight partners to operate as secondary users in frequency bands previously allocated for federal use. Uncertainty in the future regulatory environment is fueling the investigation into developing reconfigurable cognitive techniques for the next generation of communications systems. Cognitive radios are a concept of an intelligent wireless communication system that uses collected knowledge of the external environment to establish reliable communications and efficient utilization of the radio spectrum through internal parameter tuning capabilities. Collected external environmental knowledge includes radio interference levels, spectrum availability, and channel capacity. Internal parameter tuning capacities include transmit-power, carrier-frequency, and waveform modulation. Designing CRs with the above functionality across multiple decades of the frequency spectrum require tackling significant design challenges, particularly in the power amplifier section of the transmitter. The overall efficiency of a satellite’s communication system is essentially determined by the efficiency of the high-power amplifier. In micro strip or MMIC based SSPAs, harmonically-tunable power amplifiers such as, the class-F and class-F-1 amplifiers are often preferred because of their high power added efficiency. This harmonic-tuning requires specifically designed input/output matching networks containing resonant elements designed for a specific operating frequency. These matching networks are inherently narrow band, which does not allow for the wide bandwidth needed for use in a cognitive system. The works in this thesis present a new micro strip amplifier design architecture, the Compound Amplifier structure, designed to overcome the above mentioned challenges to provide high efficiency and multiple-bandwidth operation. This new approach integrates multiple harmonically tuned matching networks with a single transistor through high power switching mechanisms controlled by a cognitive radio processor. To demonstrate the proof of concept, a Compound Amplifier prototype has been designed and built to operate at both X and S Bands, in class-F- configuration, using a single GaN transistor. This prototype is analyzed for stability, efficiency and additional considerations when compared against an alternative non-switching, dual-frequency band, multi-transistor design. This work has been conducted in two phases. The first phase consists of the design, fabrication and testing of individual class-F amplifiers operating at X and S band. These individual amplifiers will be used for comparison with the multi-network, single-transistor prototype. The second phase involved the design, fabrication and testing of a multi-network, single-transistor Compound Amplifier design to determine the achievable gain, stability, output power and efficiency as well as its efficacy for use as the power amplifier to enable the functionality necessary for a cognitive transmitter. The physical demonstration of the Compound Amplifier concept is supplemented with additional simulations showing the potential expansion of the Compound Amplifier concept to a Quad-band design.
Peter Kosel, Ph.D. (Committee Chair)
Marc Cahay, Ph.D. (Committee Member)
Altan Ferendeci, Ph.D. (Committee Member)
Rashmi Jha, Ph.D. (Committee Member)
Rainee Simons, Ph.D. (Committee Member)
298 p.
Electrical Engineering
Gallium Nitride; Reconfigurable; SSPA; Class-F; Space Communications; Compound Amplifier

Recommended Citations

Citations

  • Waldstein, S. W. (2019). Compound Reconfigurable Dual-band Solid State Power Amplifier using a Single GaN HEMT for S and X-band Operations [Doctoral dissertation, University of Cincinnati]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563874650458585

    APA Style (7th edition)

  • Waldstein, Seth. Compound Reconfigurable Dual-band Solid State Power Amplifier using a Single GaN HEMT for S and X-band Operations. 2019. University of Cincinnati, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563874650458585.

    MLA Style (8th edition)

  • Waldstein, Seth. "Compound Reconfigurable Dual-band Solid State Power Amplifier using a Single GaN HEMT for S and X-band Operations." Doctoral dissertation, University of Cincinnati, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563874650458585

    Chicago Manual of Style (17th edition)

ucin1563874650458585
137
© 2019, all rights reserved.
This open access ETD is published by University of Cincinnati and OhioLINK.