Sensors within systems

The introduction of powerful and compact electronic systems which can be located within a sensor housing means that the sensor must now be treated as a sub-system of potentially great behavioural complexity. The author discusses the enabling technologies which permit the hardware and software realisation of such sub-systems and proceeds to a consideration of the relationship between the sub-system and its host system. Factors which have to be taken into account are the physical connections over which signals are passed, the high-level protocols by which information is exchange and the degree to which the variability of programmed operation can be exploited.