Results 91 to 100 of about 49,826 (236)
Joint Channel, Carrier-Frequency-Offset and Noise-Variance Estimation for OFDM Systems Based on Expectation Maximization [PDF]
, 2010 In this paper, a joint channel, carrier-frequency-offset (CFO) and noise-variance estimation scheme is proposed for OFDM systems which is based on Expectation and Maximization (EM) algorithm.
Xiaomin Mu +5 more
core +1 more source
, 2005 The achievable performance of decision-directed channel estimation (DDCE) is analysed in the context of both OFDM and MC CDMA systems. Two different estimation methods suitable for both OFDM and MC-CDMA systems are considered, which employ sample-spaced (
Akhtman, J., Hanzo, L.
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PAPR Reduction and Data Security Improvement for OFDM Technique Using Chaos System
Journal of Communications Software and Systems, 2019 Orthogonal Frequency Division Multiplexing (OFDM) is the most popular multicarrier technique because it produces several advantages such as higher spectral efficiency, high transmission rate, robustness to fading channel and etc..
Muntadher Kadhim Abdullah +1 more
doaj
Active and passive sensors for diagnostics quasi-zenith ionospheric HF communication channels
Физика волновых процессов и радиотехнические системыBackground. There is a growing need for active sensory diagnostics of partial HF channels to provide frequency support to quasi-zenith HF radio links in varying signal propagation conditions.
Dmitry V. Ivanov +3 more
doaj +1 more source
Proceedings of the International Conference on Applied Innovations in IT, 2014 In this paper we investigate various algorithms for performing Fast Fourier Transformation (FFT)/Inverse Fast Fourier Transformation (IFFT), and proper techniques for maximizing the FFT/IFFT execution speed, such as pipelining or parallel processing, and
Danijela Efnusheva +3 more
doaj +1 more source
Estudo de técnicas de formatação de feixe para transmissão OFDM [PDF]
, 2004 Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Engenharia ElétricaEsta dissertação apresenta um estudo do comportamento de diversos algoritmos adaptativos capazes de realizar a formatação
Lima, Gustavo Corrêa
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OFDMA para Sistemas de Banda Ancha Inalámbrica
Prisma Tecnológico, 2009 Este artículo describe el sistema de Acceso Múltiple por División de Frecuencia Ortogonal (OFDMA), un método de modulación para la segunda generación de acceso a banda ancha inalámbrica.
Daniel Tuñón, Ramón Ortega
doaj
On The Non-linear Distortion Effects in an OFDM-RoF Link
, 2006 Radio over Fiber (RoF) system is a promising technique for microcell and picocell applications for deployment of future ubiquitous wireless data networks.
Song, Ju Bin +3 more
core
, 2007 In this letter we characterize the substantial difference between two channel estimation approaches, namely the sample-spaced (SS) and the fractionally-spaced (FS) channel impulse response (CIR) estimators. The achievable performance of decision-directed
Akhtman, Jos, Hanzo, Lajos
core
, 2005 The number of transmit antennas that can be employed in the context of least-squares (LS) channel estimation contrived for orthogonal frequency division multiplexing (OFDM) systems employing multiple transmit antennas is limited by the ratio of the ...
M. Munster +3 more
core +1 more source