Zhaoneng Jiang

Meshed ground microstrip antennas with low radar cross section

It is proposed that the radar cross section (RCS) of a microstrip antenna can be effectively reduced over a broad frequency band by utilizing a well-designed meshed ground plane. The radiation characteristic of the microstrip antenna is only slightly influenced by cutting slots on the ground plane. The calculated results suggest that the meshed microstrip ground antenna has much lower RCS than the solid ground one over a band 1–18GHz, with a maximum reduction of 15dB, while the radiation performance of the microstrip antenna, such as gain, impedance bandwidth and so on, remains almost the same as that of the solid antenna.

Efficient analysis of multilayer microstrip structures by matrix decomposition algorithm — Singular value decomposition

In order to efficiently and accurately analyze the scattering of multilayer microstrip structures, the matrix decomposition algorithm — singular value decomposition (MDA-SVD) is used to accelerate the matrix-vector multiplication operations. MDA-SVD is purely algebraic; hence, its formulation and implementation are integral equation kernel independent. It utilizes the SVD algorithm to reduce the memory requirement and solution time of the matrix decomposition algorithm. The numerical results demonstrate the efficiency of the proposed method.

Combined MDA-SVD-MLFMA for analysis of the EM scattering from complex objects

The multilevel fast multipole algorithm (MLFMA) is very efficient for solving the three-dimensional problems, but for the small size of the complex objects, the memory usage of the multilevel fast multipole algorithm is very large. To overcome this problem, the matrix decomposition algorithm — singular value decomposition (MDA-SVD) is used to alleviate the pressure of the “strong” interaction portion of the impedance matrix of the MLFMA. So a new hybrid method named combined MDA-SVD-MLFMA is proposed. It also overcomes the problem that the matrix filling time of the far field of MDA-SVD is a little long. The numerical results demonstrate the efficiency of this method.

Matrix interpolation of the adaptive cross approximation matrix for multilayer structures problems

In order to efficiently analyze the scattering and radiation of the multilayer structures, the adaptive cross approximation (ACA) is applied to accelerate the matrix-vector multiplication operations. Although ACA is efficient compared with the direct method, the setup time of ACA is very long for the broadband problems. An efficient version of ACA is proposed in this paper. The method applies an efficient matrix interpolation technique to the matrices of ACA. Using the matrix interpolation technique, a much less setup time representation of the far field matrix is obtained. The numerical results of the multilayer structures are used to demonstrate that the efficiency of the proposed method.