Prediction of patch antenna element interaction using the transmission line matrix method

Abstract

The ability of the transmission line matrix or TLM method to model the microstrip patch antennas is investigated. The simple geometry of the patch antennas enables the TLM method to be applied easily. In theory, TLM should give good results for closely spaced elements as it does not make simplifying assumptions concerning the field distributions at the patch edges, as do some other theoretical methods. It is dependent on the coarseness error, and this can be improved by increasing the mesh resolution - a relatively simple procedure from the user's point of view. This is the motivation of this research. The thesis presents the development of simulation models, development of hardware and practical measurements, and software modifications. The development of the TLM models for the single antenna, mutually coupled two-element antennas and a broadband antenna will be described. The predicted results from these models are compared with results from another theoretical approach and published literature; specifically, the scattering parameters (i.e. reflection coefficent/return loss and the coupling coefficient) will be assessed.