2D systems theory-a common approach to problems in circuits, control and signal processing

The main aim of the paper is to give an overview of 2D systems theory, with particular emphasis on its role in control, circuits and signal processing applications. The article: (i) highlights the key differences between standard (1D) and nD systems with particular emphasis on the mathematical tools required; (ii) surveys progress in a number of key areas which stretch across the general areas of circuits, control and signal processing; and (iii) identifies some key currently open research problems.