The fractional Fourier transform (FRFT), which is a family of linear transformations generalizing the classical transform, has been used in fields filter design, signal processing, phase retrieval, and pattern recognition due to its unique properties. FRFT can be interpreted as decomposition terms chirps. In this paper, for first time, best our knowledge, we introduce an optical (OFRFT)-based o...

the destructive impact of fading environments and also bandwidth limitations are two main challenges which communication is dealing with them. these challenges can affect on the growth of wireless communication and even cause reliable communications and high data rate to be prevented. thus, ofdm (orthogonal frequency division multiplexing) modulation by using of fast calculation hardwares such ...

Abstract This paper aims to improve the channel estimation (CE) in indoor visible light communication system. The proposal of this deals with a system that depends on comparison between Deep Neural Network (DNN), Yolo v3, and Kalman filter (KF) algorithm, for two optical modulation techniques; asymmetrically clipped optical-orthogonal frequency-division multiplexing (ACO-OFDM) direct current fr...

This paper proposed a new OFDM scheme called damped zero-pseudorandom noise orthogonal frequency division multiplexing (DZPN-OFDM) scheme. In the scheme, ZPN-OFDM non-zero part to reduce guard interval energy as well mutual interference power in-between data and training blocks, conservative pseudo-noise conventional properties required for channel estimation or synchronization. The motivation ...

Orthogonal frequency division multiplexing (OFDM) is a promising technique for high-data-rate wireless communications because it can combat inter-symbol interference (ISI) caused by the dispersive fading of wireless channels. The proposed research focuses on techniques that improve the performance of OFDM based wireless communications and its commercial and military applications. In particular,...

Introduction: Orthogonal-frequency-division-multiplexing (OFDM) is a special form of multicarrier modulation where a single data stream is transmitted over a number of lower rate orthogonal subcarriers [1]. Such a format has been widely implemented in various digital communication standards. Recently we proposed an equivalent optical multicarrier modulation format, called coherent optical OFDM ...

Abstract High speed and low latency have become the development trend of mobile communication network. Orthogonal frequency division multiplexing (OFDM) technology has key network due to its efficient transmission method. Space time block coding (STBC) introduces space correlation in signals sent by different antennas, so that diversity gains are obtained for multiple input output-OFDM (MIMO-OF...

In Orthogonal Frequency Division Multiplexing (OFDM) systems, the cyclic-delay diversity (CDD)Scheme is a low-complexity means of increasing transmit diversity. Because it requires only one inverse discrete Fourier transform (IDFT) operation at the transmitter. The mean square error (MSE) of both the least square (LS) channel estimate and the minimum mean square error (MMSE) channel estimate ar...