Evolvable hardware systems using programmable analogue devices

One way of exploring the use of evolution for design of analogue systems is to use an evolutionary algorithm to suggest circuits and a software simulator to test these candidates; this is usually called 'extrinsic' evolution. In our work we are looking at evolution as a method for obtaining the set of instructions to apply to programmable analogue devices. These are devices which have been designed to process analogue signals, but the nature of the analogue operations that are performed on the signals are specified by the contents of digital registers on the device. Hence candidate circuits can be implemented immediately and tested on real signals, providing what is called 'intrinsic' evolution. Using evolutionary methods to programme these new analogue devices has the advantage not only of providing a method of automating the design process but also allows candidate designs to be drawn from a wider repertoire of combinations than would be practical for a human designer. This may allow a given performance to be obtained from a system in a more efficient way than would otherwise have been discovered.