V.M. Doroshenko1, M.S. Gavkina2

1, 2 Yu.A. Gagarin Saratov State Technical University (Saratov, Russia)
1 dorvalentina9@gmail.com, 2 april-18@inbox.ru

Traditional vector network analyzers based on eight-port circuits are characterized by high hardware complexity and cost. Alternative six-port reflectometers face the limitations of deterministic mathematical models, which ignore the stochastic nature of measurement arm errors. This forces developers to ensure a high signal-to-noise ratio, increase excitation power, and introduce additional detector linearization procedures, which reduces metrological stability and limits the applicability of devices in resource-intensive applications.

To conduct a systematic review of mathematical models and signal processing algorithms for multiport reflectometers, analyze their performance at various signal-to-noise ratio levels, and identify prospects for the development of statistical approaches in modern microwave metrology.

A comparative study of nonlinear, linear, and statistical models of multiport networks was conducted. It was shown that deterministic formulations lose effectiveness under real-world measurement noise. The advantage of a domestic statistical approach with redundant measurement channels (N+2, N≥4) was revealed. It allows for explicitly accounting for power sensor errors, jointly solving a system of equations with quadratic constraints, and reconstructing the complex reflection coefficient without strict requirements for input signal levels.

The developed data processing methods pave the way for the creation of compact and cost-effective microwave analyzers for integration into antenna-feeder paths and telecommunication systems. Eliminating complex heterodyning circuits and forced linearization simplifies hardware implementation, reduces power consumption, and increases the reliability of built-in diagnostics.

Doroshenko V.M., Gavkina M.S. Mathematical models and methods for processing signal from multi-port microwave reflectometers: a review, problems, and prospects // Achievements of modern radioelectronics. 2026. V. 80. № 6. P. 75–86. DOI: https://doi.org/10.18127/j20700784-202606-07

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