Designing High-Order Stable Variable-Phase Compensator for High-Quality Communications

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K04379
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21020:Communication and network engineering-related
• Research Institution: Toho University
• Principal Investigator: ITO NOBORU 東邦大学, 理学部, 教授 (00237041)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 通信システム / 位相特性 / 線形位相 / 非線形位相 / 位相補償

Outline of Final Research Achievements

The communication channel with nonlinear-phase characteristic distorts the original waveform of the transmitted signal after the signal passes through the nonlinear-phase channel. To prevent such waveform distortions, it is mandatory to design a phase compensator and then cascade it to the original communication channel such that the entire channel has nearly linear phase. The first stage of this study derived the phase error and frequency-response error of a recursive all-pass phase compensator, and the second stage developed several programming techniques for minimizing those errors. That is, the major contributions of this study are the developments of various minimization techniques employing a wide variety of programming algorithms, and those minimization techniques are then employed to get an optimal all-pass phase compensator. Furthermore, the robustness of the cascade phase compensator's stability has also been enhanced via more general stability-triangle conditions.

Free Research Field

信号処理

Academic Significance and Societal Importance of the Research Achievements

通信システムと信号処理システムは線形位相システムと非線形位相システムに分類されるが、非線形位相システムは信号波形を変形させ、信号処理後または信号伝送後の信号波形を変形させてしまう。このような波形歪問題は波形保持が重要な応用では避けなければならない。本研究では、波形歪問題を解決するため、全域通過型位相補償器というディジタルシステムの最適設計を行い、得られた位相補償器を非線形位相システムに接続し、システム全体の位相特性をほぼ線形位相に補償することにより、信号の波形歪問題を解決し、高品質波形伝送を実現した。