S. P. Kuksenko

New concept of critical infrastructure strengthening

Strengthening of critical infrastructure is considered. Modal reservation of electronics is proposed as a new concept of the strengthening. The concept combines a widely used cold backup and a recently proposed modal filtration. It makes electronics reliable as well as protected against electromagnetic interference, especially the ultra-wide band pulses. New printed circuit board structure is suggested for implementation of the proposed concept. Results of simulation in time and frequency domains are presented for the suggested structures. Considerable attenuation of dangerous excitations shows that the new concept and structure are promising.

Multiple solution of systems of linear algebraic equations by an iterative method with the adaptive recalculation of the preconditioner

The mean time needed to solve a series of systems of linear algebraic equations (SLAEs) as a function of the number of SLAEs is investigated. It is proved that this function has an extremum point. An algorithm for adaptively determining the time when the preconditioner matrix should be recalculated when a series of SLAEs is solved is developed. A numerical experiment with multiply solving a series of SLAEs using the proposed algorithm for computing 100 capacitance matrices with two different structures—microstrip when its thickness varies and a modal filter as the gap between the conductors varies—is carried out. The speedups turned out to be close to the optimal ones.

New results on EMC simulation for space projects of TUSUR University

The paper presents and summarizes theoretical and practical results of the UEM-TUSUR project which is focused on the development of approaches, technologies and software for EMC simulation of unified electronic modules of spaceborne equipment. Theoretical and practical results for quasi-static and electromagnetic analysis, solution of linear algebraic systems and modal filtration are presented briefly. Outlook for applications of the obtained results in the current SAN project is given.

Approximation of an initial matrix by a Toeplitz one for acceleration of iterative solution of dense linear algebraic systems in scattering problems

In iterative solution of linear algebraic systems, in order to accelerate matrix-vector multiplication by means of FFT usage, it is proposed to replace an initial matrix of a system with a Toeplitz matrix. Solution accuracy evaluation, relatively to the Gaussian elimination method, is presented. Results of usage of two BiCGStab method variants are demonstrated. The possibility to obtain up to 1.8 times speed-up (comparatively to the case without FFT acceleration) by the example of calculation of currents induced by external field in a conductive square plate is shown. An important trend of solution acceleration and accuracy increasing with increasing of N is revealed.

Modal distortions of pulse signal in multiconductor PCB structure

A problem of control and diagnostics of electrical connections is considered. A brief review of researches of modal phenomena in electrical connections along which only common and differential modes can propagate is given. A principle of modal phenomena usage for contactless detection, control and diagnostics of electrical connections is described. The results of quasi-static simulation of 9-trace structure, based on multilayer printed board, theoretically confirm the possibility of the implementation of this principle in the structures along which more than two modes can propagate. It is shown, that a method of the structure excitation can have a significant impact on both the form of modal distortions and the diagnostic capability of the electrical connections using modal probing.

Acceleration of multiple solution of a boundary value problem involving a linear algebraic system

Multiple solution of a boundary value problem that involves a linear algebraic system is considered. New approach to acceleration of the solution is proposed. The approach uses the structure of the linear system matrix. Particularly, location of entries in the right columns and low rows of the matrix, which undergo variation due to the computing in the range of parameters, is used to apply block LU decomposition. Application of the approach is considered on the example of multiple computing of the capacitance matrix by method of moments used in numerical electromagnetics. Expressions for analytic estimation of the acceleration are presented. Results of the numerical experiments for solution of 100 linear systems with matrix orders of 1000, 2000, 3000 and different relations of variated and constant entries of the matrix show that block LU decomposition can be effective for multiple solution of linear systems. The speed up compared to pointwise LU factorization increases (up to 15) for larger number and or...

Multiple solution of linear algebraic systems by an iterative method with recomputed preconditioner in the analysis of microstrip structures

A multiple solution of linear algebraic systems with dense matrix by iterative methods is considered. To accelerate the process, the recomputing of the preconditioning matrix is used. A priory condition of the recomputing based on change of the arithmetic mean of the current solution time during the multiple solution is proposed. To confirm the effectiveness of the proposed approach, the numerical experiments using iterative methods BiCGStab and CGS for four different sets of matrices on two examples of microstrip structures are carried out. For solution of 100 linear systems the acceleration up to 1.6 times, compared to the approach without recomputing, is obtained.