A.A. Nikitin1, V.V. Vitko2, A.A. Emelyanov3, A.B. Ustinov4

1–4 Saint-Petersburg State Electrotechnical University (LETI) (Saint Petersburg, Russia)

3 JSC «KNIRTI» (Zhukov of Kaluga Region, Russia)

1aanikitin@etu.ru, 2vitaliy.vitko@gmail.com, 3eaa15@knirti.ru, 4Ustinov_rus@yahoo.com

Introduction. High-precision measurement of the angular coordinates of radio emission sources is an urgent task of modern digital radio interferometers. The main measured parameter in these devices is the totality of the phase differences of the signal received and digitized by spaced receiving channels. To achieve high measurement accuracy, it is necessary first of all to minimize the difference-phase errors in digitizing the received signal by spaced receiving channels. In addition, the placement of radio interferometers at most objects involves solving the problems of minimizing the size of the system, its weight, power consumption and cost. To optimally solve these problems, it is proposed to use fiber-optic communication lines with their own low phase noise, where a tuning switchable optical delay line, made in an integral design, is used as a tool for correcting the phase mismatch of the synchronization signal transmission channels.

The purpose of this work is to evaluate the possibility of constructing an integrated optical delay line for a microwave signal using silicon-on-insulator technology with the possibility of further use in fiber-optic communication lines as a tool for correcting the phase mismatch of synchronization signal transmission channels.

The object of study was the design of an integrated-optical tuning delay line used to compensate for phase distortions of microwave signals in fiber-optic communication lines resulting from uneven temperature distribution. The device consists of a cascade connection of integrated directional couplers on coupled waveguides, performing the functions of controlled switches, as well as integrated optical signal delay lines.

This paper proposes a design for an integrated optical tuning delay line, consisting of a cascade connection of integrated directional couplers on coupled waveguides that perform the functions of controlled switches, as well as integrated optical signal delay lines. The paper presents the results of modeling directional couplers that provide complete signal switching between arms as a result of heating by 50°C, as well as integral delay lines used to compensate for the thermal incursion of the microwave envelope phase with a step of 4°. The proposed design can be used to compensate for phase distortions that occur in fiber-optic communication lines.

Nikitin A.A., Vitko V.V., Emelyanov A.A., Ustinov A.B. Integral-optical triming delay line for application in fiber optical communication lines. Radioengineering. 2023. V. 87. № 11. P. 47−53. DOI: https://doi.org/10.18127/j00338486-202311-08 (in Russian)

1. Emelyanov A.A. Postroenie fazostabilnoi sistemy sinkhronizatsii ATsP raznesennykh priemnykh kanalov radiointerferometra s ispolzovaniem elementov radiofotoniki. Radiotekhnika. 2018. № 11. S. 110−114. (in Russian)
2. Emelyanov A.A. i dr. Osobennosti postroeniya bortovoi volokonno-opticheskoi sinkhroseti. Radiotekhnika. 2017. № 8. S. 121−126. (in Russian)
3. Bogaerts W. et al. Nanophotonic waveguides in silicon-on-insulator fabricated with CMOS technology. Journal of Lightwave Technology. 2005. V. 23(1). P. 401−412.
4. Izhaky N. et al. Development of CMOS-compatible integrated silicon photonics devices. IEEE Journal of Selected Topics in Quantum Electronics. 2006. V. 12(6). P. 1688−1698.
5. Vlasov Y.A., McNab S.J. Losses in single-mode silicon-on-insulator strip waveguides and bends. Optics express. 2004. V. 12(8). P. 1622−1631.
6. Chrostowski, Lukas, Michael Hochberg. Silicon photonics design: from devices to systems. Cambridge University Press. 2015.
7. Bradley J. Frey, Douglas B. Leviton, Timothy J. Madison. Temperature-dependent refractive index of silicon and germanium. Proceedings SPIE. 2006. V. 6273. P. 62732J–62732J–10. doi: 10.1117/12.672850.