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arXiv · 1805.00362

A code-free optical undersampling technique for broadband microwave spectrum measurement

Guangyu Gao·Xueshuang Xiang·Qijun Liang·Naijin Liu
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Abstract

A novel broadband microwave (MW) spectrum measurement (BMSM) scheme based on code-free optical undersampling and homodyne detection is proposed. The fully analog generation of optical pulses with a far-less-than-Nyquist rate is only through modulating cascaded electrooptical modulators by a single RF tone instead of any high-speed coding sequence modulation. Homodyne detection will reduce the analysis bandwidth of BMSM and enhance the detection performance of weak signal. A multi-band signal with 20 GHz spectral range and SNR = 61 dB is used to investigate the BMSM performance of this scheme, and the results show good performance for BMSM. The potentials for further optimization in practice are also discussed.

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Guangyu Gao, Xueshuang Xiang, Qijun Liang, Naijin Liu. 2018-04-29. A code-free optical undersampling technique for broadband microwave spectrum measurement. https://arxiv.org/abs/1805.00362

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