Results 81 to 90 of about 24,612 (214)

CRLBs for Pilot-Aided Channel Estimation in OFDM System under Gaussian and Non-Gaussian Mixed Noise [PDF]

open access: yes, 2012
The determination of Cramer-Rao lower bound (CRLB) as an optimality criterion for the problem of channel estimation in wireless communication is a very important issue. Several CRLBs on channel estimation have been derived for Gaussian noise.
Huang, J. Y., Shen, X. F., Wang, P.
core   +1 more source

Modeling the Intermediate Flow Regime in Flow‐Compensated Intravoxel Incoherent Motion MRI

open access: yesMagnetic Resonance in Medicine, Volume 95, Issue 6, Page 3476-3487, June 2026.
ABSTRACT Purpose The intravoxel incoherent motion (IVIM) model is commonly used to separate the effects of motion related to diffusion and blood microcirculation (perfusion) on the MR signal. Depending on the encoding time (T), it is possible to probe the different temporal regimes of blood motion, which resemble a ballistic flow at short T and a ...
Louise Rosenqvist   +5 more
wiley   +1 more source

The Power Gain Difference Method Analysis

open access: yesSensors, 2020
In this paper, we propose a new approach to passively locate the 3D position of a signal source. This novel technique, called the power gain difference (PGD), is based only on measuring the received signal strength (RSS) with multiple sensors deployed in
Jiří Veselý   +2 more
doaj   +1 more source

Applications of the van Trees inequality : a Bayesian Cramér-Rao bound [PDF]

open access: yes, 2001
We use a Bayesian version of the Cramer-Rao lower bound due to van Trees to give an elementary proof that the limiting distibution of any regular estimator cannot have a variance less than the classical information bound, under minimal regularity ...
Gill, R.D., Levit, B.Y.
core  

Toward Optimized Intravoxel Incoherent Motion (IVIM) and Compartmental T2 Mapping in Abdominal Organs

open access: yesMagnetic Resonance in Medicine, Volume 95, Issue 6, Page 3161-3175, June 2026.
ABSTRACT Purpose To quantitatively assess the bias in the intravoxel incoherent motions (IVIM)–derived pseudo‐diffusion volume fraction (f) caused by the differences in relaxation times between the tissue and fluid compartments, and to develop a two‐dimensional (b‐value‐TE) fitting approach for simultaneous T2 and IVIM parameter estimation along with ...
Julia Stabinska   +4 more
wiley   +1 more source

Existence of unbiased estimators in discrete quantum systems

open access: yesPhysical Review Research
The Cramér-Rao bound serves as a crucial lower limit for the mean square error of an estimator in frequentist parameter estimation. Paradoxically, it requires highly accurate prior knowledge of the estimated parameter for constructing the optimal ...
Javier Navarro   +2 more
doaj   +1 more source

Complementary Sensitivity of Fixed‐Time and Fixed‐Oscillation Regimes to Exchange and Structural Disorder in the Human Brain Revealed Using Oscillating‐Gradient Diffusion MRI With Ultra‐Strong Gradients

open access: yesMagnetic Resonance in Medicine, Volume 95, Issue 6, Page 3429-3444, June 2026.
ABSTRACT Purpose Oscillating‐gradient spin‐echo (OGSE) diffusion MRI probes cell geometry and membrane integrity through the frequency‐dependence of kurtosis, but prior studies have reported inconsistent findings depending on how frequency is varied. We compared frequency‐dependent kurtosis in the human brain under two regimes: varying frequency with ...
Dongsuk Sung   +8 more
wiley   +1 more source

Posterior Cramer‐Rao lower bound for wireless sensor localisation networks

open access: yesElectronics Letters, 2018
A general closed expression of posterior Cramer‐Rao lower bound (PCRLB) for wireless sensor networks is derived and presented, based on Bayesian estimation and well suited to dynamic systems. The aim is to guide the localisation algorithm design and anchor layout fulfilling certain accuracy requirement.
Siming Li, Jing Lv, Shiwei Tian
openaire   +1 more source

Estimators, escort probabilities, and phi-exponential families in statistical physics

open access: yes, 2004
The lower bound of Cramer and Rao is generalized to pairs of families of probability distributions, one of which is escort to the other. This bound is optimal for certain families, called phi-exponential in the paper.
Naudts, Jan
core  

Aerial Anchors Positioning for Reliable RSS-Based Outdoor Localization in Urban Environments

open access: yes, 2017
In this letter, the localization of terrestrial nodes when unmanned aerial vehicles (UAVs) are used as base stations is investigated. Particularly, a novel localization scenario based on received signal strength (RSS) from terrestrial nodes is introduced.
Azari, Mohammad Mahdi   +3 more
core   +1 more source

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