Electronics Letters, 2023 Estimating instantaneous frequencies (IFs) overlapped in both time and frequency domains is an important issue in time‐frequency (TF) analysis. In this letter, the TF information of the signal in fractional domain is combined with an optimization ...
Liyun Xu, Wei Li
doaj +1 more source
SignalFormer: Hybrid Transformer for Automatic Drone Identification Based on Drone RF Signals
Sensors, 2023 With the growing integration of drones into various civilian applications, the demand for effective automatic drone identification (ADI) technology has become essential to monitor malicious drone flights and mitigate potential threats.
Xiang Yan +3 more
doaj +1 more source
A general theory on frequency and time–frequency analysis of irregularly sampled time series based on projection methods – Part 2: Extension to time–frequency analysis [PDF]
Nonlinear Processes in Geophysics, 2018 Geophysical time series are sometimes sampled irregularly along the time axis. The situation is particularly frequent in palaeoclimatology. Yet, there is so far no general framework for handling the continuous wavelet transform when the time sampling ...
G. Lenoir, M. Crucifix, M. Crucifix
doaj +1 more source
A general theory on frequency and time–frequency analysis of irregularly sampled time series based on projection methods – Part 1: Frequency analysis [PDF]
Nonlinear Processes in Geophysics, 2018 We develop a general framework for the frequency analysis of irregularly sampled time series. It is based on the Lomb–Scargle periodogram, but extended to algebraic operators accounting for the presence of a polynomial trend in the model for the data,
G. Lenoir, M. Crucifix, M. Crucifix
doaj +1 more source
Phase Difference Compensation Method for Range Estimation in an MFCW–CW Radar
IEEE Access, 2021 Multifrequency continuous-wave–continuous-wave (MFCW–CW) radars simultaneously transmit multifrequency continuous-wave (MFCW) signals sequentially at a constant time step and a continuous-wave (CW) signal constantly.
Chungho Ryu, Chungyong Lee
doaj +1 more source
Deep Learning Aided Time–Frequency Analysis Filter Framework for Suppressing Ionosphere Clutter
Remote Sensing, 2022 In a heterogeneous environment, the ionosphere is dynamically changing in the Earth’s middle latitude, and backscatter from fast-moving irregularities in the plasma can cause ionosphere clutter to extend.
Xiaowei Ji +5 more
doaj +1 more source
Frontiers in Human Neuroscience, 2021 ObjectiveWe quantitatively analyzed high-frequency oscillations (HFOs) using scalp electroencephalography (EEG) in patients with infantile spasms (IS).MethodsWe enrolled 60 children with IS hospitalized from January 2019 to August 2020. Sixty healthy age-
Lisi Yan +29 more
doaj +1 more source
Improving Ship Detection in Clutter-Edge and Multi-Target Scenarios for High-Frequency Radar
Remote Sensing, 2021 As one of the main sensors for continuous maritime measurements of sea state parameters, high-frequency surface wave radar (HFSWR) also plays an important role in ship detection and tracking.
Zhiqing Yang +4 more
doaj +1 more source
Laser Ultrasonic Automatic Detection Method for Surface Microcracks on Metallic Cylinders
Photonics, 2023 Metallic cylinders are widely used in various fields of industrial production, and the automatic detection of surface microcracks is of great significance to the subsequent grinding process.
Yanjie Zhang +7 more
doaj +1 more source
An Estimation and Compensation Method for Motion Trajectory Error in Bistatic SAR
Remote Sensing, 2022 Bistatic synthetic aperture radar (BiSAR) has drawn increasing attention in recent studies benefiting from its ability for forward-looking imaging, its capability of receiver radio silence and its resistance to jamming.
Yi Li +5 more
doaj +1 more source