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Creators/Authors contains: "Xu, Chengtao"

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  1. ; ; (, IEEE)
    Free, publicly-accessible full text available September 24, 2025
  2. ; ; (, IEEE Space Hardware and Radio Conference)
    This study presents a novel design for a microlens coupler to transfer light from a straight waveguide to a single-mode fiber (SMF). Our design combines improved mode matching and enhanced alignment tolerance compared to edge coupling. An investigation of the alignment tolerance is done by assessing coupling efficiency under various degrees of manufacturing-induced misalignment. Singlet and diffractive lenses are incorporated into our design to focus the light into the fiber precisely. Comprehensive simulations demonstrate that the diffractive lens outperforms edge coupling and singlet lens in coupling efficiency. Fabrication methods such as additive manufacturing are discussed for future works. Our findings underscore the potential of innovative microlens coupler design. 
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    Accepted Manuscript Full Text Available
  3. ; ; ; ; ; ; (, IEEE Internet of Things Journal)
    Full Text Available 
  4. ; ; ; ; (, ICASSP 2021 - 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP))
    null (Ed.)
    Radio frequency (RF) signal classification has significantly been used for detecting and identifying the features of unknown unmanned aerial vehicles (UAVs). This paper proposes a method using empirical mode decomposition (EMD) and ensemble empirical mode decomposition (EEMD) on extracting the communication channel characteristics of intruding UAVs. The decomposed intrinsic mode functions (IMFs) except noise components are selected for RF signal pattern recognition based on machine learning (ML). The classification results show that the denoising effects introduced by EMD and EEMD could both fit in improving the detection accuracy with different features of RF communication channel, especially on identifying time-varying RF signal sources. 
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    Full Text Available 
  5. ; ; (, 2020 IEEE 39th International Performance Computing and Communications Conference (IPCCC))
    null (Ed.)
    Full Text Available