Liu Jiangfan

Application of MW-FDTD to simulate EM wave propagation in plasma for long distance

To reduce the computational burden of normal finite-difference time-domain (FDTD) method, moving window technique was used here to predict the electromagnetic wave propagation in plasma slab. The stretched coordinate perfectly matched layer (SC-PML) with complex frequency shifted (CFS) equations was applied to absorb the backward reflection. This technique can save considerable computation resources for long propagation distance, and the high accuracy of MW-FDTD method is confirmed by compare these results to the analytical solution and full model FDTD method results.

Loran-C ground-wave propagation prediction based on the hybrid FDTD algorithm

The hybrid FDTD algorithm is proposed for long-range Loran-C ground-wave propagation prediction, especially for the complex path. In this paper, the computational domain is divided into two parts, the ordinary FDTD method with fine-grid and higher-order FDTD with coarse-grid are combined for the prediction. The subgrid technique is introduced to analyze and transfer the electromagnetic fields of different domain. The results show that the proposed algorithm improves computational efficiency greatly while maintaining comparable accuracy with the traditional FDTD using high-grid resolution.

Adaptive nulling array antenna using a new variable step size LMS-type algorithm

A adaptive array antenna system consisting of antenna array and adaptive processor can easily control directivity patterns, by enhance the desired signal and suppress interference signal. The classical LMS has a contradiction that fast convergence rate and low steady state error. In order to overcome this contradiction, this paper presents a new algorithm which uses gradient vector features to achieve iterative step. The software simulation results verify the effectiveness of the algorithm.