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arXiv · 1808.06971

Microwave Hilbert Transformer and its Applications in Real-time Analog Processing (RAP)

Xiaoyi Wang·Zoé-Lise Deck-Léger·Lianfeng Zou·José Azaña·Christophe Caloz
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Abstract

A microwave Hilbert transformer is introduced as a new component for Real-time Analog Processing (RAP). In contrast to its optical counterpart, that resort to optical fiber gratings, this Hilbert transformer is based on the combination of a branch-line coupler and a loop resonator. The transfer function of the transformer is derived using signal flow graphs, and two figures of merits are introduced to effectively characterize the device: the rotated phase and the transition bandwidth. Moreover, a detailed physical explanation of its physical operation is given, using both a steady-state regime perspective and a transient regime perspective. The microwave RAP Hilbert transformer is demonstrated experimentally, and demonstrated in three applications: edge detection, peak suppression and single sideband modulation.

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Xiaoyi Wang, Zoé-Lise Deck-Léger, Lianfeng Zou, José Azaña, Christophe Caloz. 2018-08-21. Microwave Hilbert Transformer and its Applications in Real-time Analog Processing (RAP). https://doi.org/10.1109/tmtt.2019.2905596

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