S.I. Babusenko1, A.V. Zhuravlev2, V.V. Kiryushkin3, V.A. Shuvaev4

1-4 JSC RIE “PROTEK” (Voronezh, Russia)

1 serbs@mail.ru; 2,4 protek@protek-vrn.ru; 3 kiryushkin.vlad@mail.ru

Problem statement. The high quality of communication services provided by the Starlink low-orbit satellite communication system is determined not only by adaptive algorithms for spatial re-targeting in the relay group, but also by the processing of signal and code structures in the presence of adverse destabilizing factors.Modeling of proprietary physical and data link layer protocols is difficult due to the lack of a complete description, which makes it impossible to predict transmission rates in the channel, taking into account additive interference and the number of active subscribers.In this regard, the task of developing a model for generating an onboard repeater radio signal with the ability to evaluate the potential performance of the system is relevant.

Purpose. To perform modeling of the basic protocols of the channel and physical layers of the Ku-band downlink radio line of the low-orbit satellite communication system Starlink to evaluate the data transfer rate in the conditions of Gaussian interference based on the revealed and published features of the implementation of the Starlink signal structure.

Results. A software model has been developed for generating an OFDM frame of a downlink signal containing primary and secondary sync signals, header and information OFDM symbols with side pilot signals and service T-codes. The achievable transmission rate in a frequency channel was estimated for various signal-code structures and different numbers of subscribers served in a single beam.

Practical significance. The given performance indicators allow us to estimate the potential throughput of the Starlink satellite communication system in the presence of additive Gaussian interference.

Babusenko S.I., Zhuravlev A.V., Kiryushkin V.V., Shuvaev V.A. Analysis of the Ku-band downlink signal of the low-orbit Starlink satellite communication system based on a software model // Radiotekhnika. 2026. V. 90. № 7. P. 93−103. DOI: https://doi.org/10.18127/j00338486-202607-17

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