Results 21 to 30 of about 15,290 (259)
Multi-Weight Unipolar Codes for Multimedia Spectral-Amplitude-Coding Optical CDMA Systems [PDF]
IEEE Communications Letters, 2004 A novel balanced detection scheme for multi-access interference cancellation in multimedia spectral-amplitude-coding optical code-division multiple-access system is proposed. The receiver is capable of handling both equal and unequal in-phase cross correlation of optical orthogonal codes.
Ivan B. Djordjevic +2 more
openaire +3 more sources
The Journal of Engineering, 2019 In modern digital communication systems, a high-order modulation and advanced channel coding are often jointly used to increase the spectral efficiency and coding gain.
Sung-Joon Park +2 more
doaj +1 more source
Enhanced adaptive code modulation for rainfall fade mitigation in Ethiopia
EURASIP Journal on Wireless Communications and Networking, 2022 Rain attenuation is considerably noticed in a frequency spectrum above 7-GHz for tropical equatorial regions and in a frequency spectrum higher than 10-GHz for temperate climates.
Eyob Mersha Woldamanuel +1 more
doaj +1 more source
Quantifying vocal mimicry in the greater racket-tailed drongo: a comparison of automated methods and human assessment. [PDF]
PLoS ONE, 2014 Objective identification and description of mimicked calls is a primary component of any study on avian vocal mimicry but few studies have adopted a quantitative approach. We used spectral feature representations commonly used in human speech analysis in
Samira Agnihotri +3 more
doaj +1 more source
Modulation and Signal Processing for LEO-LEO Optical Inter-Satellite Links
IEEE Access, 2023 We investigate key aspects of coherent optical communications on inter-satellite links (ISLs) for the next-generation ultra-dense low-Earth orbit (LEO) constellations.
I. P. Vieira, T. C. Pita, D. A. A. Mello
doaj +1 more source
Variable-Weight Optical Code Division Multiple Access System using Different Detection Schemes
Journal of Telecommunications and Information Technology, 2016 In this paper a Variable Weight OCDMA (VWOCDMA) system using KS code with Direct Decoding (DD), Complementary Subtraction (CS) and AND subtraction detections is proposed.
Saleh Seyedzadeh +2 more
doaj +1 more source
Application and Analysis of Performance of DQPSK Advanced Modulation Format in Spectral Amplitude Coding OCDMA [PDF]
Mehran University Research Journal of Engineering and Technology, 2014 SAC (Spectral Amplitude Coding) is a technique of OCDMA (Optical Code Division Multiple Access) to encode and decode data bits by utilizing spectral components of the broadband source.
Abdul Latif Memon +2 more
doaj
IEEE Access, 2019 A spectral efficient light emitting diode (LED)-based visible light communication (VLC) system adopting polar-coded 128 quadrature-amplitude modulations (QAM) orthogonal frequency division multiplexing (OFDM) is experimentally demonstrated.
JING He +5 more
doaj +1 more source
An Effective Spatial Modulation Based Scheme for Indoor VLC Systems
IEEE Photonics Journal, 2022 We propose an enhanced spatial modulation (SM)-based scheme for indoor visible light communication systems. This scheme enhances the achievable throughput of conventional SM schemes by transmitting higher order complex modulation symbol, which is ...
Shimaa Naser +4 more
doaj +1 more source
The Shewanella oneidensis Fic enzyme SoFic targets the switch‐I region of EF‐Tu for AMPylation
FEBS Letters, EarlyView.Fic enzymes mediate diverse post‐translational modifications across all domains of life, including AMPylation. Prokaryotic EF‐Tu can be AMPylated and deAMPylated by the conserved Fic enzyme SoFic. Structural and biochemical approaches were used to characterize the effect of AMPylation on EF‐Tu, SoFic's enzymatic activities, and the enzyme‐target ...
Svenja Runge +6 more
wiley +1 more source