A. D. Poligina1, A. V. Taganov2, Yu. P. Salomatov3
1, 2 JSC «NPP «Radiosvyaz» (Krasnoyarsk, Russia)
1, 3 Siberian Federal University (Krasnoyarsk, Russia)

1 anastasia0711@mail.ru, 2 AVTaganov@yandex.ru, 3 ysalomatov@sfu-kras.ru

The development of compact millimeter-wave satellite terminals requires the creation of co-located emitters capable of operating efficiently in separate receive and transmit frequency channels. Existing solutions based on microstrip technologies (such as the use of higher-order modes, cascading, or coplanar emitter placement) often suffer from low gain, narrow bandwidth, difficulty generating the required polarizations, and significant channel interference.

The aim of this work is to develop and analyze the design of a co-located dual-band microstrip emitter using a spatial multiplexing architecture and a simple geometric method for generating counter-directional circular polarizations.

The article presents the design and analysis results of a compact four-element microstrip antenna array combining the receiving (19…21.5 GHz) and transmitting (43…46 GHz) ranges in a single 9x9 mm2 aperture. The design is based on the use of aperture coupling through H-shaped slots excited by symmetrical striplines. The key feature is the formation of multidirectional circular polarization (right/left) in different ranges due to the spatial rotation of the radiating rectangular patches relative to the slots by angles of ±45°. The receiving channel is realized by one enlarged patch, the transmitting channel by three identical patches placed in the corners of the aperture. The results of electrodynamic modeling confirmed the high characteristics: the total matching bandwidth is greater than 18% in each range; the gain in the receiving range is 6.1 dB, in the transmitting range is 11.9 dB; the ellipticity coefficient in the operating frequency ranges exceeds 0.7; the channel-to-channel isolation exceeds 30 dB.

The proposed emitter provides high aperture efficiency and a simple circular polarization generation scheme. The design is a ready-made element for building compact and lightweight antenna systems designed for modern K/Q-band satellite communication platforms.

Poligina A.D., Taganov A.V., Salomatov Yu.P. Combined K/Q-band microstrip emitter with aperture coupling and multidirectional circular polarization // Antennas. 2026. № 3. P. 55–63. DOI: https://doi.org/10.18127/j03209601-202603-05

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