The analysis of medium-sized arrays of complex elements using a combination of FDTD and reaction matching

The analysis of medium-sized arrays of complex antenna elements by means of a full-wave technique often requires impractical amounts of computer power. Nevertheless, it is essential that all the mutual couplings between elements are taken into account. A technique is presented in which the individual element is characterized using the FDTD method and, using the information this provides, the behavior of the complete array is predicted using a method based on reaction matching. Results using this method are compared to measurement and to results obtained using a complete full-wave analysis for three- and five-element arrays of printed dipoles. The error introduced by the approximation is shown to be small in most cases. For arrays of between 10 and 50 elements, savings in computer time of several orders of magnitude can be achieved and, in addition, changes in array geometry do not always necessitate all the results being recalculated.