Functional magnetic resonance (fMRI) studies intend to answer neuroscience questions by statistically analyzing a set of acquired images. Thereby, the aim is to determine those regions in the brain image in which the signal changes upon stimulus presentation. Although MR data are intrinsically complex valued, most tests are commonly applied to magnitude MR images, because these images have the ...

This paper shows that the proposed Rician shadowed model for multi-antenna communications allows for the unification of a wide set of models, both for multiple-input multiple output (MIMO) and single-input single output (SISO) communications. The MIMO Rayleigh and MIMO Rician can be deduced from the MIMO Rician shadowed, and so their SISO counterparts. Other SISO models, besides the Rician shad...

M. Nezamzadeh, I. Cameron Physics, Carleton University, Ottawa, ON, Canada, Radiology, The Ottawa Hospital, Ottawa, ON, Canada Introduction: It is well known that pixel intensities of magnitude MR images are biased by Rician noise [1-4]. This is particularly noticeable for SNR ≤ 2. Rician noise bias corrections from the literature [2,3] work well for SNR > 2 but not for SNR < 2. Furthermore, th...

We characterize the performance of energy detector (ED) over square-law, square-law selection, and switch-and-stay diversity combining schemes. The exact average probabilities of a miss (Pm), and a false alarm (P f ) are derived in closed-form. To derive Pm for versatile Nakagami-m and Rician fading channels, a twofold approach, using the probability density function (PDF) and the moment genera...

© 2010 ETRI Journal, Volume 32, Number 3, June 2010 In this letter, we analyze the error performance of a mobile communication system with microdiversity and macrodiversity reception in gamma-shadowed Rician fading channels for a binary differential phase-shift keying modulation scheme. Analytical expressions for the probability density function (PDF) and moment-generating function (MGF) are de...

Simple closed-form solutions for the average error rate of several coherent modulation schemes including square M-QAM, DBPSK and QPSK operating over slow flat Rician fading channel are derived. Starting from a novel unified expression of conditional error probability the error rates are analysed using PDF based approach. The derived end expressions composed of infinite series summations of Gaus...

Modern wireless communication systems support high speed multimedia services. These services require high data rates with acceptable error rates. Orthogonal Frequency Division Multiplexing (OFDM) is a capable candidate to solve this problem. In this paper, a new expression for the BER of OFDM system has been derived over Nakagami–n (Rice) fading channels using characteristics function (CHF) app...

MRI is one of the most powerful techniques to study the internal structure of the body. MRI image quality is affected by various noises. Noises in MRI are usually thermal and mainly due to the motion of charged particles in the coil. Noise in MRI images also cause a limitation in the study of visual images as well as computer analysis of the images. In this paper, first, it is proved that proba...

We address the problem of robust estimation of tissue microstructure from Diffusion Magnetic Resonance Imaging (dMRI). On one hand, recent hardware improvements enable the acquisition of more detailed images, on the other hand, this comes along with a low Signal to Noise (SNR) ratio. In such a context, the approximation of the Rician acquisition noise as Gaussian is not accurate. We propose to ...

Conventionally fading analysis of wireless LAN or MAN means small scale fading i.e. wide fluctuation of received signal with small variation of time and distance. In analysis of fading channel we consider the received signal in power, voltage or SNR as a random variable then statistical probability density function (pdf) like Rayleigh, Rician or Nakagami-m is used to get the probability of diff...