Efficient Solution of Integral-Equation Based Electromagnetic Problems With the Use of Macromodels

Abstract

Fig. 5. Comparison of the full-wave simulated patterns and the measured patterns in [10]: (a) f (1.56 GHz). (b) f + prf and f + 2prf. to the measured SLL of about 028:32 dB. Fig. 5(b) shows the full-wave simulated sideband patterns at the first and second sidebands, in comparison with the measured results in [10]. The simulated peak sideband levels are 012:19 and 017:81 dB at the first and second sidebands, close to the measured levels of 013:09 and 021:05 dB in [10], respectively. In general, the full-wave simulated sideband patterns are in reasonable agreement with the measured sideband patterns in [10]. IV. CONCLUSIONIn this communication, we have proposed a frequency-domain full wave approach to simulate the TM linear antenna arrays. By decomposing the time-domain excitations into frequency-domain amplitude and phase excitations at the central modulating frequency as well as the sideband frequencies, the TM linear arrays can be simulated using conventional frequency-domain full-wave simulation approach. Consequently, the space and frequency responses of the TM linear arrays can be obtained through combinations of the space patterns at the respective central modulating frequency and sideband frequencies. The proposed approach was applied to the full-wave simulations of L-band printed dipole TM linear arrays with VAS time modulation schemes.The full-wave simulation results are in reasonable agreement with reported measurement results, thus demonstrating the effectiveness of the proposed approach. suppression in time-modulated linear arrays by the differential evolution algorithm," "Design of a uniform amplitude time modulated linear array with optimized time sequences," IEEE Trans.Abstract-The idea of so-called macromodels is applied to problems of computational electromagnetics involving integral-equation/method-of-moments formulations. It is shown that with the use of equivalence principles, it is possible to exclude a part of the problem, calculate its wideband response without an a priori knowledge of the excitations, and then efficiently combine the result into the original situation. The idea is validated using examples involving slot-excited dielectric resonator antennas. Index Terms-Domain decomposition, integral equations, method of moments (MoM).

The Application of Macromodels to the Analysis of a Dielectric Resonator Antenna Excited by a Cavity Backed Slot

“…In this section, we will present how a combination of AWE with the Domain Decomposition Method (DDM), introduced by one of the authors in [10], can be used to solve the described problem very effectively. The outline of the procedure is as follows:…”

“…Then, we take the term in curly braces, namely: 3. And finally, we find the Padé approximation to the entries of Z M using the procedure given in [10].…”

“…2. In this case the final system of equations to be solved reduces to [10]: For consistency with the previous formulas, we have left in (9) superscript c describing the environment below the slot (although there is no cavity in this case). Also note the change of excitation to the magnetic type, as now it is the slot that is excited, not the metallization.…”

“…In the situations where the feeding system must be optimised such approach leads to an unacceptable computational burden, since every minor modification on the "cavity" side provokes long-lasting computations. In this paper we propose a remedy to the aforementioned drawback, and the main idea is based on the Integral Equation Macromodels (IEMs) [10], which combine the domaindecomposition method (DDM) with the fast frequency sweep technique, i.e. the asymptotic waveform evaluation method (AWE).…”