E.V. Gusev1, T.Yu. Shumilov2, D.S. Shishkin3

1-3 JSC «SPР «Radiosviaz’» (Krasnoyarsk, Russia)

1 paramid@ro.ru

This article explores the application of GAP structures as an alternative to conventional radio-absorbing materials for power amplifiers in the millimeter wave range. The relevance of this task is driven by the need to enhance the quality characteristics and stability against selfexcitation of millimeter wave power amplifiers. Despite the rapid growth in the production of millimeter wave power amplifiers for satellite communication stations, most commercially available power amplifier models exhibit low stability against self-excitation due to parasitic couplings within the amplifier and power modules, where monolithic integrated circuits serve as the key components of the power amplifiers. The goal of this work was to develop and investigate locking structures as an alternative to radio-absorbing materials for suppressing parasitic couplings and, consequently, self-excitation in solid-state power amplifiers in the millimeter wave range. The work presents results from electromagnetic modeling, design solutions, and experimental findings. It is shown that in the absence of radio-absorbing materials installed within the power m odules and directly inside the amplifier housing, the power amp lifier enters a self-excitation mode when operating at negative temper atures due to the increased gain of the monolithic integrated c ircuits, leading to the formation of parasitic couplings within t he power modules and the amplifier housing. The experimental re sults using a GAP structure when the power amplifier operates at negative temperatures are also presented. The

practical significance of this work lies in enhancing the s tability of power amplifiers against self-excitation and extend ing the lifespan of power amplifiers without the need for periodic main tenance and replacement of consumables, such as radio-absorbing materials, due to their aging and loss of key properties. The o btained results are of interest to developers of high-frequency equipment for satellite communication systems, where high reliabilit y of the equipment is required, along with stringent demands fo r electromagnetic compatibility and stringent requirements for operation under various temperature conditions.

Gusev E.V., Shumilov T.Yu., Shishkin D.S. The use of GAP structures in millimeter-wave power amplifiers as an alternative to radio-absorbing materials. Achievements of modern radioelectronics. 2026. V. 80. No 3. P. 32–39. DOI: https://doi.org/10.18127/j20700784-202603-05 [in Russian]

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