Extensions and variations to the microstrip antenna concept

The extensions and variations to the microstrip-antenna concept described are vastly different in application, and emphasise both the ingenuity that has already been experienced and the fund of innovative ideas that will continue to be created in future years. It was stated in Chapter 1 that the inspiration for innovation lies in the demands made by new systems, and this is well illustrated by the efforts on one hand to exert more control of radiation patterns, and on the other to increase bandwidth by an order. In each case one parameter is optimised at the expense of the others in a way which is compatible with the system constraints prevailing, but above all it is the microstrip technology that is diluted by other construction techniques to effect the desired optimisation. As already mentioned, it is a sign of maturity in a technology when a designer has learnt just how to exploit selectively its best features with confidence.