Frequency Selective Surfaces (FSSs) consist of two dimensional arrays of conductive
elements mounted on a dielectric substrate. FSSs act as passive filters to microwave
radiation. The frequency response of the filter is primarily controlled by the dimensions
and shape of the elements. The frequency selective propeny of a conventional FSS
cannot be altered once it is installed.
By positioning two FSSs so they are parallel and closely coupled to each other a double
layer FSS is created. If one FSS is moved across the plane of the other the frequency
response of the double layer FSS alters. A method of moving the FSS using piezoelectric
materials has been investigated. This allows the frequency response of the double layer
FSS to be altered, or reconfigured, after it has been installed.
Suitable piezoelectric materials were studied and methods of utilising them in a
Reconfigurable FSS (RFSS) were considered. Computer models and frequency response
measurements of conventional FSSs were used to establish the design criteria necessary
to maximise the variation in frequency response of the RFSS.
RFSSs were designed, modelled, and manufactured. Their frequency responses were then
measured. The results of the computer models and measurements were compared and
used along with knowledge of manufacturing problems to reiterate the design criteria and
produce an RFSS with greater reconfigurability.
A Master's Thesis. Submitted in partial fulfilment of the requirements for the award of Master of Philosophy of Loughborough University.