Several different paths for future research exist for this model. Primarily, the cou-pling between the slot antenna elements is calculated using the voltage distribution across the slot. The model for the voltage distribution, derived in Section 2.1.2, is a modal analysis on the different waveforms that can exist on the slot antenna under a certain configuration. The weighting of the different modes is an approximation based on the relation between the modal propagation constants and the driven prop-agation constant on the slot antenna. This expression could be improved which
The design could also be made more robust and able to tolerate fabrication er-rors, allowing for smaller designs. By modifying the ring resonator end loads so that they could be physically larger, the margin for error in the fabrication process would increase and higher frequency designs could be created. The other parame-ters of the antenna, such as the length of the slot, would need to be changed as well to account for the shift in load impedance.
Future work also includes offset biasing by having different voltages on the end loads of the same element. This technique could account for a change in impedance of the media surrounding the antenna, such as when the antenna is set down or something is set on top of it that it was not initially designed for. Different loads could also be tested to provide a better impedance match or to improve the recon-figurable range of the antenna. Also, as mentioned in Section 5.1.2, if a method to control the coupling between the elements could be established, then the spacing between the elements would cease to become a limiting factor to the performance of the array. This work opens up several research topics that could be explored and would improve both the model presented here as well as future designs of dual reconfigurable antennas.
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