By studying the super-orthogonal space-time coding designs for 2 transmit antennas and superquasi orthogonal space-time coding designs for 4 transmit antennas,a novel super-orthogonal space-time coding design for 4 tr...
详细信息
By studying the super-orthogonal space-time coding designs for 2 transmit antennas and superquasi orthogonal space-time coding designs for 4 transmit antennas,a novel super-orthogonal space-time coding design for 4 transmit antennas is *** exploiting the inherent structure association between OSTBC and QOSTBC,the proposed schemes can obtain the full-rate and good performance while keeping the coding complexity as super-orthogonal space-time coding schemes for 2 transmit *** results demonstrate that the proposed schemes outperforms the existing super-quasi orthogonal space-time coding schemes by almost 2 dB.
The fractal dimension of sea clutter is estimated and its multifractal features are analyzed in this paper. A new method based on the difference between multifractal spectra of sea clutter and target plus sea clutter ...
详细信息
The fractal dimension of sea clutter is estimated and its multifractal features are analyzed in this paper. A new method based on the difference between multifractal spectra of sea clutter and target plus sea clutter is proposed to detect targets in sea clutter. The verification of real sea clutter shows that this method is useful and has low computation burden. So it provides a new idea and an effective method to detect low observable targets in sea clutter.
Diffusion kurtosis imaging (DKI), an extension of diffusion tensor imaging (DTI), provides a practical method to describe non-Gaussian water diffusion in neural tissues. The sensitivity of DKI to detect the subtle cha...
详细信息
ISBN:
(纸本)9781424441198
Diffusion kurtosis imaging (DKI), an extension of diffusion tensor imaging (DTI), provides a practical method to describe non-Gaussian water diffusion in neural tissues. The sensitivity of DKI to detect the subtle changes in several chosen brain structures has been studied. However, intuitive and holistic methods to validate the merits of DKI remain to be explored. In this paper, tract-based spatial statistics (TBSS) was used to demonstrate white matter alterations in both DKI and DTI parameters in preschool children (1-6 years;n=10). Correlation analysis was also performed in multiple regions of interest (ROIs). Fractional anisotropy, mean kurtosis, axial kurtosis and radial kurtosis increased with age, while mean diffusivity and radial diffusivity decreased significantly with age. Fractional anisotropy of kurtosis and axial diffusivity were found to be less sensitive to the changes with age. These preliminary findings indicated that TBSS could be used to detect subtle changes of DKI parameters on the white matter tract. Kurtosis parameters, except fractional anisotropy of kurtosis, demonstrated higher sensitivity than DTI parameters. TBSS may be a convenient method to yield higher sensitivity of DKI.
Diffusion tensor imaging (DTI) has been widely used for nondestructive characterization of microstructures of myocardium or brain connectivity. It requires repeated acquisition with different diffusion gradients. The ...
详细信息
Diffusion tensor imaging (DTI) has been widely used for nondestructive characterization of microstructures of myocardium or brain connectivity. It requires repeated acquisition with different diffusion gradients. The long acquisition time greatly limits the clinical application of DTI. In this paper, a novel method, named model-based method with joint sparsity constraint (MB-JSC), effectively incorporates the prior information on the joint sparsity of different diffusion-weighted images in direct estimation of the diffusion tensor from highly undersampled k-space data. Experimental results demonstrate that the proposed method is able to estimate the diffusion tensors more accurately than the existing method when a high net reduction factor is used.
A weight constrained total least-square(WCTLS) is developed for source localization by using time difference of arrival(TDOA) *** WCTLS algorithm not only exploits the structure information of the measurement matrix,b...
详细信息
A weight constrained total least-square(WCTLS) is developed for source localization by using time difference of arrival(TDOA) *** WCTLS algorithm not only exploits the structure information of the measurement matrix,but also utilizes the prior knowledge of the TDOA *** bias and covariance of the proposed WCTLS algorithm are also *** results show that the proposed estimator achieves better performance than that of the constrained total least square,and it attains the Cramer-Rao lower bound at a sufficiently low noise level.
Recently, Gutiérrez-Naranjo and Leporati considered performing basic arithmetic operations on a new class of bioinspired computing devices - spiking neural P systems (for short, SN P systems). However, the binary...
详细信息
A network code assisted HARQ system considering uplink (UL) transmission with multiple mobile stations (MSs) cooperating with a relay-station (RS) is proposed. The RS is assumed to successfully monitor and decode the ...
详细信息
In this article, we consider the problem of joint optimization of multi-input multi-output (MIMO) radar waveform and biased estimator with prior information on targets of interest in the presence of signal-dependent n...
In this article, we consider the problem of joint optimization of multi-input multi-output (MIMO) radar waveform and biased estimator with prior information on targets of interest in the presence of signal-dependent noise. A novel constrained biased Cramer-Rao bound (CRB) based method is proposed to optimize the waveform covariance matrix (WCM) and biased estimator such that the performance of parameter estimation can be improved. Under a simplifying assumption, the resultant nonlinear optimization problem is solved resorting to a convex relaxation that belongs to the semidefinite programming (SDP) class. An optimal solution of the initial problem is then constructed through a suitable approximation to an optimal solution of the relaxed one (in a least squares (LS) sense). Numerical results show that the performance of parameter estimation can be improved considerably by the proposed method compared to uncorrelated waveforms.
We present numerical simulations performed with a two-mass model of the vocal folds. We use the model to compute the fundamental frequency, the duty ratio and the intensity of volume velocity as a function of two cont...
详细信息
暂无评论