A Time-Varying Communications Approach to Decentralized Fixed Modes

A simple approach to eliminating fixed modes in linear decentralized systems is presented and evaluated. The method uses complex exponential time-varying gains that are not in the form of feedback. These gains perform the same function as a modulator in a communication system. An example demonstrates these concepts and points out the need to choose the gain parameter carefully. These ideas should also prove useful in measurement and control applications on systems that are in some sense close to possessing a fixed mode. A pressure transducer example illustrates this point. This paper deals only with the case of 2×2 transfer functions and simple fixed modes.