Results 1 to 10 of about 20,191 (260)
Journal of Marine Science and Engineering, 2021 Velocity is vital information for navigation and oceanic engineering. Coherent Doppler sonar is an accurate tool for velocity measurement, but its use is limited due to velocity ambiguity.
Peng Liu, Nobuyoshi Kouguchi, Ying Li
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Generalized Doppler effect for high-accuracy frequency shift measurement [PDF]
Light: Science & ApplicationsLaser Doppler effect enables a wide range of precision measurements. However, its traditional implementations, including linear, rotational, and vectorial forms, have historically been treated as isolated phenomena, and meanwhile, their accuracy is ...
Yanxiang Zhang +3 more
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Joint block estimation and attention-based long short-term memory network for doppler shift mitigation in UWA communication systems [PDF]
Scientific ReportsAiming to address the performance degradation of OFDM systems caused by Doppler shift in underwater acoustic (UWA) communications, this paper proposes a two-step algorithm that combines the traditional block estimation method with an Attention-based Long
Qingxi Zeng +3 more
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IEEE Photonics Journal, 2023 In this article, the wavelength division multiplexing (WDM) technology is applied to the space chaotic laser communication system. We deduce the bit error rate (BER) model of multi-channel space chaotic laser communication with Doppler frequency shift ...
Mi Li +5 more
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All-Optical Pulsed Signal Doppler Frequency Shift Measurement System
IEEE Photonics Journal, 2021 A simple and all-optical Doppler frequency shift (DFS) measurement system is presented. It is based on a dual-drive Mach Zehnder modulator (DDMZM) driven by a transmitted signal and an echo signal received by an antenna.
Chongjia Huang, Erwin H. W. Chan
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IEEE Access, 2022 Weighted fractional Fourier transform encrypted chaotic direct sequence spread spectrum (WFRFT-CD3S) signal is aperiodic and complex Gaussian distributed.
Jiangyan He +3 more
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A Doppler Shift Factor Estimation Method for High Speed Mobile Underwater Acoustic Communication [PDF]
Jisuanji gongcheng, 2016 In underwater acoustic communication systems,most of the Doppler shift factor estimation methods cannot deal with the relationship between computational complexity and estimation accuracy under high relative motion speed.In view of this,this paper ...
YANG Jie,ZHOU Shengyuan,YU Fengqi
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Micro-Doppler Parameters Extraction of Precession Cone-Shaped Targets Based on Rotating Antenna
Remote Sensing, 2022 Micro-Doppler is regarded as a unique signature of a target with micro-motions. The sophisticated recognition of the cone-shaped targets can be realized through the micro-Doppler effect.
Zhihao Wang +4 more
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Leida xuebao, 2019 Doppler center shift is an important parameter for Synthetic Aperture Radar(SAR) to retrieve ocean surface wind field and ocean surface current field. We present a calculation method of Doppler centroid shift for airborne side-looking SAR.
ZHAO Xianbin +4 more
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Multi-frequency observations of E-region HF radar aurora [PDF]
Annales Geophysicae, 2003 Multi-frequency observations of E-region coherent backscatter from decametre waves reveal that auroral echoes tend to comprise two spectral components superimposed, one at low Doppler shifts, below 250 ms-1, and the other Doppler shifted to near ...
S. E. Milan, M. Lester, N. Sato
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