Results 31 to 40 of about 1,422 (198)

Effect of Nonlinear Phase Variation in Optical Millimetre Wave Radio over Fibre Systems [PDF]

Journal of Electrical and Computer Engineering Innovations, 2015
In this paper, we propose an optical millimetre wave radio-over-fibre (mm-wave RoF) system that uses a dual drive Mach Zehnder modulator (DD-MZM), which is biased at the maximum transmission biasing point, to generate an optical double sideband ...
A. Bahrami, W. Pang Ng, Z. Ghassemlooy, T. Kanesan   +3 more
doaj   +1 more source

Integrated Ultrasonic Platform for Bioelectronic Control through Biological Barriers Based on Metasurface

Advanced Science, EarlyView.
A metasurface‐enabled ultrasonic platform achieves precise multi‐focal control through biological barriers, real‐time physiology‐driven modulation, and simultaneous wireless power and data transmission. By unifying wavefront engineering, closed‐loop feedback, and acoustic communication, this work establishes key enabling technologies toward scalable ...
Chuanxin Zhang, Hanjie Xiao, Xue Jiang, Dean Ta   +3 more
wiley   +1 more source

Hardware-Efficient Phase Estimation for Digital Coherent Transmission With Star Constellation QAM

IEEE Photonics Journal, 2010
In order to build optical transmission systems for 100 Gb/s and above on a single wavelength division multiplexing channel, transition from quadrature phase-shift keying (QPSK) to higher quadrature amplitude modulation (QAM) formats seems to be ...
Sebastian Hoffmann, Christian Wördehoff, Ali Al-Bermani, Mohamed El-Darawy, Kidsanapong Puntsri, Ulrich Rückert, Reinhold Noé   +6 more
doaj   +1 more source

Compensation for In-Phase/Quadrature Phase Mismatch in Coherent Free-Space Optical QPSK Communication Systems

Applied Sciences, 2021
The Gram–Schmidt orthogonalization procedure (GSOP) and Löwdin symmetric orthogonalization procedure (SYOP) are the two mainstream algorithms for the compensation of phase mismatch in an imperfect optical 90° hybrid.
Xueliang Li, Tianwen Geng, Yucong Gu, Ruotong Tian, Shijie Gao   +4 more
doaj   +1 more source

Optical Windows for Transcranial Brain Imaging in Living Mice: Skull Thinning, Clearing, and Beyond

Advanced Science, EarlyView.
Longitudinal, noninvasive in vivo imaging is crucial for studying brain physiology. Advances in transcranial optical windows and multiphoton microscopy have improved imaging depth, but their performance often deteriorates over time. This work investigated various transcranial window approaches and found that skull regrowth limits image quality.
Yiming Fu, Gewei Yan, Zhentao She, Yingzhu He, Kangqi Liu, Jianan Qu   +5 more
wiley   +1 more source

Variable‐length balanced codes for quadrature phase shift keyed systems

The Journal of Engineering, 2015
The authors outline an approach to construct capacity‐approaching balanced quadrature phase shift keyed (QPSK) codes. These codes ensure an equal number of different symbol values and many symbol transitions in the encoded sequence in order to assist practical demodulators to accurately recover symbol values.
Xin Tu, Ivan J. Fair
openaire   +2 more sources

Ferroelectric Behavior of Micro‐ to Submicron‐Scale HZO Capacitors: Impact of the Perimeter‐to‐Area Ratio

Advanced Electronic Materials, EarlyView.
Using C‐AFM, W/HZO/p‐Ge capacitors with areas down to 0.26 µm2 are investigated. Frequency‐dependent voltage ramps reveal switching currents that confirm complete polarization reversal across the entire electrode area, while PUND enables reconstruction of P–V loops.
Lucian Trupina, Stefan Neatu, Lucian Pintilie, Lucia Nicoleta Leonat, Stavros Kitsios, Stefania Skorda, Alexandros El Sachat, Polychronis Tsipas, Alexander Flasby, Laura Bégon‐Lours, Athanasios Dimoulas   +10 more
wiley   +1 more source

Performance of Coherent Optical MPSK in Underwater Turbulent Channels With Phase Errors

IEEE Photonics Journal
Compared to intensity modulation with direct detection, coherent detection offers superior receiver sensitivity, higher spectral efficiency, and better background noise suppression.
Jiashun Hu, Yuexiang Wu, Sunan Wang, Weiqiang Wu, Zaichen Zhang   +4 more
doaj   +1 more source

Dictionary‐based weak‐form training for noise‐robust series hybrid models with multiplicative unknowns

AIChE Journal, EarlyView.
ABSTRACT Hybrid modeling combines first‐principles equations with a data‐driven subcomponent. Training for the data‐driven part is sensitive to measurement noise when training targets are constructed using pointwise time derivatives. Beyond differentiation errors, hybrid models involve solving an inverse problem to estimate the data‐driven term, which ...
Hangjun Cho, Akshay Kudva, Parth Shah, Dongheon Lee, Joseph Sang‐Il Kwon   +4 more
wiley   +1 more source

Receiving of direct-sequence spread spectrum signal with quadrature phase-shift keying in case of multiple access interference and internal Gaussian noise

Известия высших учебных заведений России: Радиоэлектроника, 2015
Receiving of the broadband phase modulated signal with quadrature phase-shift keying in case of multiple access in-terference and internal Gaussian noise has been considered.
G. S. Nakhmanson, S. V. Kozlov
doaj