V-band Solid-State Power Amplifier (65-71 GHz)

QuinStar Technology proposes to develop an efficient, solid-state power amplifier (SSPA), operating at V-band frequencies in support of NASA Earth and planetary science applications.nbsp;This proposal addresses the critical need for high-efficiency, millimeter-wave amplifiers used in absorption radar for remote pressure sensing to improve weather models. Specifically, we propose to develop a pulsed power amplifier with a minimum duty cycle of 25% operating over the 65-71 GHz band. The output power of the SSPA is specified to be more than 10nbsp;Watts throughoutnbsp;the band of 65-to-71nbsp;GHz with an associated PAE ofnbsp;more than 30%.nbsp;The efficiency and power goals of this program will be realized by employing a combination of state-of-the-art (SOA) device technology, innovative circuit design, and power combining techniques.Simulations of the MMIC design using 90 nm GaN HEMT from Qorvonbsp;indicatenbsp;that the power-added-efficiency (PAE)nbsp;of 33%nbsp;in thenbsp;MMIC can be achieved across the band fromnbsp;65 to 71 GHz with an associated output power of 2.8 W. We propose to realizenbsp;the specified SSPA power level (gt;10 W) withnbsp;high-efficiency waveguide circuit combining techniques.nbsp;Anbsp; high-efficiency, 4-way H-tee combiner network was designed in the Phase I program to combine four MMICs and deliver an output power of more than 10 Watts. Thenbsp;combining efficiencies of the 4-way H-tee combiner is simulated greater than 94% in the band of interest, which translates into a PAE of 31% in the SSPA. The compactnbsp;size and light weight of the SSPA are projected 2.2nbsp;x 2.0 x 1.0 inches and 6 oz. respectively,nbsp;which make itnbsp;suitable for application to CubeSat/SmallSat platforms.