Results 21 to 30 of about 89,588 (266)
Doppler Wind Lidar From UV to NIR: A Review With Case Study Examples
Frontiers in Remote Sensing, 2022 Doppler wind lidar (DWL) uses the optical Doppler effect to measure atmospheric wind speed with high spatial-temporal resolution and long detection range and has been widely applied in scientific research and engineering applications.
Mingjia Shangguan +7 more
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A self-coherent receiver for detection of PolMUX coherent signals
Optics Express, 2012 A self-coherent receiver capable of demultiplexing PolMUX-signals without an external polarization controller is presented. Training sequences are introduced to estimate the polarization rotation, and a decision feedback recursive algorithm mitigates the random walk of the recovered field.
Li, Jingshi +10 more
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Detection of coherence-disrupting and coherence-conferring alterations in text [PDF]
Memory & Cognition, 1985 In a study phase, subjects were presented with sentence pairs which were either coherent or anomalous. In a subsequent recognition test, each sentence pair was presented either in its original form or with one word changed. The changed word either disrupted the coherence of a previously coherent sentence pair or conferred coherence on a previously ...
J J, Bharucha, K L, Olney, P P, Schnurr
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On the Performance of Coherent OFDM Systems in Free-Space Optical Communications
IEEE Photonics Journal, 2015 This paper presents a new model of a coherent orthogonal frequency division multiplexing free space optical communication (OFDM-FSO) system that can be tuned with the virtual local oscillator, under the Gamma-Gamma atmospheric turbulence channel, not ...
Yi Wang, Deli Wang, Jing Ma
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IEEE Photonics Journal, 2023 This paper experimentally investigates the perform-ance of free-space optical (FSO) communication based on mode diversity reception (MDR) using nonmode selective photonic lantern (NSPL) and equal gain combining (EGC).
Feng Wang +3 more
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IEEE Photonics Journal, 2012 We propose a millimeter-wave (MMW) coherent radio-over-fiber (RoF) transmission system for application to an access network with a direct broadband last-mile wireless connection to an optical fiber network.
A. Kanno +7 more
doaj +1 more source
Portable Pulsed Coherent Lidar for Noncooperation Targets at the Few-Photon Level
Sensors, 2021 The decoherence in coherent lidar becomes serious with the increase in distance. A small laser spot can suppress the decoherence of the echo light from noncooperation targets. However, it is very difficult to keep a small light spot over a long distance.
Chengkai Pang +3 more
doaj +1 more source
Recent Advances in Coherent Optical Communications for Short-Reach: Phase Retrieval Methods
Photonics, 2023 Short-reach transmission systems traditionally utilize intensity modulation (IM) at the transmitter and direct detection (DD) at the receiver due to their cost-effectiveness, small footprint, and low power consumption.
Abdullah S. Karar +4 more
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Digital self-coherent detection
Optics Express, 2008 We review recent progresses on digital self-coherent detection of differential phase-shift keyed (DPSK) signal using orthogonal differential direct detection followed by high-speed analog-to-digital conversion and digital signal processing (DSP). Techniques such as data-aided multisymbol phase estimation for receiver sensitivity enhancement, unified ...
Xiang, Liu +2 more
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Coherent and Noncoherent Detection CPFSK
IEEE Transactions on Communications, 1974 Continuous phase frequency shift keying (CPFSK) is potentially an attractive modulation scheme for use on channels whose performance is limited by thermal noise. In this paper results for the performance available with CPFSK are given for coherent detection and noncoherent detection with arbitrary modulation indices and arbitrary observation intervals.
Osborne, William P., Luntz, Michael B.
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