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Array Pattern (array + pattern)

Distribution by Scientific Domains

Life Sciences	50%
Engineering	33%

Selected Abstracts

The performance analyses of multitarget CMA adaptive array considering mutual coupling and diffraction effects

INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 7 2007
Jin Xu
Abstract The performance of a multitarget constant modulus algorithm (MU-CMA) adaptive array located on a regular conducting plate is studied in this paper. The effects of mutual coupling (MC) between array elements and diffraction caused by the conducting plate are taken into account. A hybrid method of equivalent edge current method (ECM) and moment method (MM) is employed in electromagnetic calculation to investigate the distortion of initial array pattern. We compare the capture property of three well-known MU-CMA arrays, respectively: multitarget least-squares constant modulus array (MT-LSCMA), multitarget decision-directed array (MT-DD) and least-squares despread respread multitarget constant modulus array (LS-DRMTCMA). Simulation result shows that: (i) the distorted initial pattern leads to the descending of the signal catch performance of MT-LSCMA and MT-DD; (ii) only the LS-DRMTCMA can work correctly due to its stronger anti-jamming ability in the presence of MC and diffraction. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Edge-adaptive color interpolation for complementary color filter array

INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 3 2006
Young Seok Han
Abstract Complementary color filter array (CCFA) is widely used in consumer-level digital video cameras, since it not only has high sensitivity and good signal-to-noise ratio in low-light condition but also is compatible with the interlaced scanning used in broadcast systems. However, the full-color images obtained from CCFA suffer from the color artifacts such as false color and zipper effects. These artifacts can be removed with edge-adaptive color interpolation (ECI) approaches which are generally used in primary color filter array (PCFA). Unfortunately, the unique array pattern of CCFA makes it difficult that CCFA adopts ECI approaches. Therefore, to apply ECI approaches suitable for CCFA to color interpolation is one of the major issues to reconstruct the full-color images. In this paper, we propose a new ECI algorithm for CCFA. To estimate an edge direction precisely and enhance the quality of the reconstructed image, a function of spatial variances is used as a weight, and new color conversion matrices are presented for considering various edge directions. Experimental results indicate that the proposed algorithm outperforms the conventional method with respect to both objective and subjective criteria. © 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 16, 92,102, 2006 [source]

Amplitude-only pattern nulling of linear antenna arrays with the use of an immune algorithm

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 5 2008
Kerim Guney
Abstract This article presents an optimization immune algorithm (opt-IA) for null steering of linear antenna arrays by controlling only the element amplitudes. Nulling of the pattern is also achieved by controlling the phase-only and the complex weights (both the amplitude and phase) of the array elements. The opt-IA is a new evolutionary computing algorithm based on the clonal selection principle of immune system. To show the accuracy and flexibility of the proposed opt-IA, several examples of Chebyshev array pattern with the imposed single, multiple, and broad nulls are given. It is found that the nulling technique based on opt-IA is capable of steering the array nulls precisely to the undesired interference directions. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. [source]

Distribution of FMR1 and FMR2 alleles in Javanese individuals with developmental disability and confirmation of a specific AGG-interruption pattern in Asian populations

ANNALS OF HUMAN GENETICS, Issue 2 2001
SULTANA M. H. FARADZ
The number of trinucleotide repeats in the 5, untranslated regions of the FMR1 and FMR2 genes was determined by PCR in 254 Fragile XA-negative Javanese male children with developmental disabilities. The distribution of FMR1 and FMR2 trinucleotide repeat alleles was found to be significantly different in the Indonesian population with developmental disability compared to that in developmentally disabled populations in North America and Europe (p < 0.021). Sequence analysis was performed on the trinucleotide repeat arrays of the 27 individuals with FMR1 alleles in the ,grey zone' (35,54 repeats). A repeat array structure of 9A9A6A9 was found in 16 unrelated individuals with 36 repeats, confirming earlier observations in intellectually normal Japanese. We propose that this FMR1 array pattern is specific for Asian populations and that Javanese and Japanese populations arose from a single progenitor population. [source]

Manipulation of microparticles for construction of array patterns by negative dielectrophoresis using multilayered array and grid electrodes

BIOTECHNOLOGY & BIOENGINEERING, Issue 4 2009
Kosuke Ino
Abstract In this study, a useful method was developed to fabricate array patterns of microparticles not on electrode surfaces, but on arbitrary surfaces, using negative-dielectrophoresis (n-DEP). First, electrodes were designed and electric field simulations were performed to manipulate microparticles toward target areas. Based on the simulation results, multilayered array and grid (MLAG) electrodes, consisting of array electrodes surrounded by insulated regions and a grid electrode, were fabricated for the formation of localized, non-uniform electric fields. The MLAG electrode was mounted to a target substrate in a face-to-face configuration with a spacer. When an AC voltage (4.60,Vrms and 1,MHz) was applied to the MLAG electrode, array patterns of 6 and 20,µm diameter microparticles were rapidly fabricated on the target substrate with ease. The results suggest that MLAG electrodes can be widely applied for the fabrication of biochips including cell arrays. Biotechnol. Bioeng. 2009; 104: 709,718 © 2009 Wiley Periodicals, Inc. [source]