Evaluating the performance of virtual sensors

The term virtual sensor refers to a mechanism used for reconstructing missing, or difficult to obtain, measurements from available data. Typically, a signal model is employed as an integral part of all virtual sensors. Virtual sensors are core building blocks in a wide range of technological systems including control, communications, biomedical, radar and environmental. In this paper, we review design trade-offs for virtual sensors. We show that there are fundamental and unavoidable limitations associated with their performance. The results can be utilized to assess the desirability, or otherwise, of using a virtual sensor in a given application. The implications of the results in feedback control are also briefly explored