In this paper, we investigate the effects of impulsive noise on the DS/SSMA systems using TCM. We obtain the probability of bit error bound of the systems, considering both impulsive noise and Rician fading unavoidable in mobile communication environments. It turns out that we can achieve some coding gain by using TCM under impulsive noise environment at moderate to high signal to noise ratio (...

An analytical expression of the cumulative distribution function (cdf) of the normalized signal-to-noise ratio SNR of the maximum ratio combiner (MRC) in correlated Rician fading channels has been derived. The expression is expressed as an infinite power series which can be computed very fast by truncation to a finite number of terms. The analytical expression can handle any number of receiving...

Purpose: To investigate the robustness of four fitting methods for bi-component effective spin-spin T2 (T2*) relaxation time analysis of human patellar tendon. Methods: A three-dimensional (3D) cone ultrashort echo-time (UTE) sequence was performed on the knees of ten healthy volunteers at 3.0T. Four fitting methods incorporating either Gaussian or Rician noise distribution were used for voxel-...

Denoising is critical for improving visual quality and reliability of associative quantitative analysis when magnetic resonance (MR) images are acquired with low signal-to-noise ratios. The classical non-local means (NLM) filter, which averages pixels weighted by the similarity of their neighborhoods, is adapted and demonstrated to effectively reduce Rician noise without affecting edge details ...

Cognitive radio is an emerging technology, which aims to upgrade the spectrum utilization by allowing the secondary users to operate at the spectrum bands vacated by the primary users. A cognitive radio system model was simulated and the performance of the energy detector was evaluated by using different wireless channel models. These models include Additive White Gaussian Noise (AWGN) model, R...

INTRODUCTION MRI magnitude images are often corrupted by Rician distributed noise and a contrast-reducing signal-dependent bias [1]. Reduction of Rician noise is desirable, especially in low signal-to-noise ratio (SNR) images such as those found in diffusion tensor imaging (DTI). Many methods have been proposed to reduce noise in diffusion weighted imaging (DWI), including maximum likelihood es...

| In this paper, we design parallel concatenated convolutional codes (PCCCs) for trellis coded modulation (TCM) over the following discrete two-dimensional (2D) channels: (a) a slow-fading Rayleigh channel with discrete carrier tracking by a phase locked loop (PLL), where the PLL signal-to-noise ratio (SNR) is proportional to the fading amplitude squared; (b) an additive white Gaussian noise (A...

The image intensity in magnetic resonance magnitude images in the presence of noise is shown to be governed by a Rician distribution. Low signal intensities (SNR < 2) are therefore biased due to the noise. It is shown how the underlying noise can be estimated from the images and a simple correction scheme is provided to reduce the bias. The noise characteristics in phase images are also studied...