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 numerical modelling technique often requires impractical amounts of computer power. Nevertheless, it is essential that all the mutual couplings between elements are taken into account. In this contribution, a technique is presented in which the individual element is characterised using the FDTD method and, using the information this provides, the behaviour 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 and are shown to be in good agreement. 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.