In this paper, a multiscale compressed and spliced Sherman-Morrison-Woodbury algorithm (MSCS-SMWA), based on the characteristic basis function method (CBFM), has been presented to accelerate direct solutions of electromagnetic scattering. The impedance matrix or reduced can be into block diagonal matrices with adaptive cross approximation (ACA) easily obtained inverse method. MSCS-SMWA is combined ACA singular value decomposition (SVD). numerical results several perfect electric conducting...

In this paper, a fast adaptive cross approximation (FACA) algorithm and the characteristic basis function method (CBFM) are presented to accelerate computing processing in using multiscale compressed block decomposition (MS-CBD) direct solutions of electrically large problems. The impedance matrix or reduced can be into matrices MS-CBD structure FACA. With recursive inversion processes on matrix, it is easy obtain solutions. Combined with sampling method, speed calculation FACA proved much...

A high‐resolution imaging system for short‐range personnel security screening based on a novel multiple‐input‐multiple‐output (MIMO) array is presented. It overcomes the problem of specular reflection which occurs in most state‐of‐the‐art mono‐static‐based configuration. Prior to portal‐based architecture, this able reconstruct three‐dimensional (3D) image whole body and detect concealed weapon secret while passenger walking through hallway or intersection, potential realising reconfigurable...

The simulation of the millimeter wave imaging system for whole body screening before a safety inspection manufactured is challenging work. conventional physical optics (PO) method proper high-frequency approximation to solve forward problem imaging. In this letter, modified PO used calculate not only metal scatterer but also nonmetal dielectric medium. A ray tracing and its modification are proposed further fast estimate performance multiple-input-multiple-output (MIMO) system. radiation...

Millimeter wave radar has the advantage of all-day and all-weather capability for detection, speed measurement. It plays an important role in urban traffic flow monitoring safety monitoring. The conventional 2-dimensional Fast Fourier Transform (2DFFT) algorithm is performed target detection range-Doppler domain. However, motion will induce range walk phenomenon, which leads to a decrease energy performance To solve above problems, this paper proposes moving vehicle based on Keystone-2DFFT...

The extremely low frequency (ELF) electromagnetic (EM) wave propagation parameters are obtained and studied based on the simulated Schumann resonances (SRs). To obtain SRs, ELF EM environment of Earth-ionosphere (E-I) system rigorously using geodesic finite-difference time-domain (FDTD) method. Prony's method is introduced to analyze simulation results for obtaining SR parameters. After that, analytical methods combined with SRs applied including attenuation rate phase velocity. Using above...

Recent research on implantable system provides available technology to the retinal prosthesis. Via penetrating microelectrodes into brain and stimulating optic nerve, device could evoke visual percepts in humans, which can use restoring lost vision. However, how employ component control process of data energy produce innocent efficient bioelectric signal finally is rather difficult task. The technique wireless communication programmed current source give a feasible way. particular design for...

An auxiliary differential equation (ADE) finite-difference time-domain (FDTD) method is applied to analyze the effect of ionospheric high frequency (HF) heating on electromagnetic (EM) wave propagation. First ionosphere background parameters in East China generated from IRI are introduced study model and nonlinear phenomenon during process at low altitude between 60 120km simulated. Then vertical distribution electron temperature initial saturation condition used simulate EM propagation...

The propagation of a sinusoidal wave is simulated in simplified model two-dimensional (2-D) local ionosphere using novel implicit auxiliary differential equation (ADE) finite-difference time-domain (FDTD) method combined with layer smoothing (LS) technique. Impacts both the diurnal variation and natural geomagnetic field on are taken into account. It found that this FDTD has same stability condition as free space regardless plasma parameters, which flexible wide variety simulation applications.

An independent sideband (ISB) is a promising scheme for short-reach and metro applications because of its high spectral efficiency, low complexity, tolerance to chromatic dispersion. Here, we develop signal synthesis further reduce the complexity ISB direct-detection (DD) systems. Two lower-order quadrature amplitude modulation (QAM) signals are generated digitally, then left (LSB) right (RSB) modulated with regular phase shift keying (QPSK) geometrically shaped shifted QPSK (GS-S-QPSK),...

Driven by the "double carbon" goal, security of wind power integrated system is importance and highlighted. The open circuit fault in switch PMSG drive often occurs, with high concealment obvious load characteristics. Generally, data-driven diagnosis method needs try many times to find feature parameters, choose several them obtain large sample size distinguish fault. To solve these shortages, a based on cluster analysis proposed this paper. features are projected into 3-D space. These...

Ground-based synthetic aperture radar (GBSAR) is widely used in mountains, mines, and other areas because it can get the sub-millimeter deformation information of monitoring scenes. This technology plays a vital role safeguarding production operations, providing accurate disaster projections, facilitating timely early warning dissemination. However, moving target’s defocus/displaced signal will mask image GBSAR, which affects accuracy inversion. Hence, detection targets GBSAR imagery...

Electrical stimulation of the optic nerve has been identified as a form visual prosthesis to restore lost vision in blind patients affected by retinitis pigmentosa and age-related macular degeneration, through many studies experiments. Magnetic transcutaneous coupling is frequently used for power transfer implanted electronic devices. In such prosthetic device, how improve efficiency we can get precise DC voltage output are two most challengeable elements whole system design. This paper...

This paper presents a MIMO imaging system, which has good effect and higher resolution. The equations for the position of antennas are deduced in detail. proposed algorithm is used to carry out inverse scattering microwave image through near-field scattered electric field obtained by simulation software. formulas resolution antenna array presented this paper. main factors influence quality analyzed, accuracy feasibility formula verified complex object, provides valuable reference method...

The millimeter wave imaging has become an efficient way to detect threat object concealed under cloth by whole-body screening. However, noise due sparse antenna arrays deteriorates the quality of reconstructed image. How alleviate this problem is a challenging work. In paper, idea called K-means clustering which usually presented in machine learning field introduced reduce simply kicking off irrelevant section apart from main body domain. Such method straightforward and easy implement. Its...