We consider Discrete Multitone (DMT, baseband OFDM) modulation and perform a detailed noise analysis which takes into account dependencies and power differences of real and imaginary part after the complex valued discrete Fourier transform (DFT). We show that for colored noise rotated rectangular symbol constellations are more appropriate than the common (quadratic) QAM symbol constellations wi...

This paper deals with the performance of the use of fractional Fourier transform (FRFT) instead of conventional Fourier transform (FFT) in either symbol timing offset (STO) and carrier frequency offset (CFO) estimation. Orthogonal frequency division multiplexing is widely used in many systems due to advantages of theses technique compared with mono-carrier systems. In spite of his advantages, O...

In this study, a novel Fractional Fourier transform (FrFT) based pilot symbol assisted modulation (FPSAM) technique for channel estimation has been proposed. In FPSAM, the received pilot symbols are processed in fractional Fourier domain before being used for channel estimation. In practice, the channel estimation is done by sending known training (pilot) symbols along with the information symb...

We prove estimates for solutions of the Cauchy problem for the inhomogeneous wave equation on R in a class of Banach spaces whose norms only depend on the size of the space-time Fourier transform. The estimates are local in time, and this allows one, essentially, to replace the symbol of the wave operator, which vanishes on the light cone in Fourier space, with an inhomogeneous symbol, which ca...

First, this study obtained the fields of an Airy beam (AiB) with optical vortex (OV) for a Fourier transform (FT) system and a fractional Fourier transform (fractional FT) system; thereafter, their intensity and phase patterns were simulated numerically. The splitting on each line of the phase pattern indicates the position of an OV. The results show that the OV position will change when the po...

Finite Radon Transform mapper has the ability to increase orthogonality of sub-carriers, it is non sensitive to channel parameters variations, and has a small constellation energy compared with conventional Fast Fourier Transform based orthogonal frequency division multiplexing. It is also able to work as a good interleaver which significantly reduces the bit error rate. Due to its good orthogo...

Abstract. We consider Linsker’s neural network model, in particular, development of oriented receptive fields of cells on layer G, and investigate which features in this model are crucial for the development. We assume that the correlation function is a Mexican-hat shape function while we introduce the arbor function explicitly and discuss its role in the development. We compute the Fourier tra...