Modern Signal Processing

Underlying many of the current mathematical opportunities in digital signal processing are unsolved analog signal processing problems. For instance, digital signals for communication or sensing must map into an analog format for transmission through a physical layer. In this layer we meet a canonical example of analog signal processing: the electrical engineer’s impedance matching problem. Impedance matching is the design of analog signal processing circuits to minimize loss and distortion as the signal moves from its source into the propagation medium. This paper
works the matching problem from theory to sampled data, exploiting links between H1 theory, hyperbolic geometry, and matching circuits. We apply J. W. Helton’s significant extensions of operator theory, convex analysis, and optimization theory to demonstrate new approaches and research pportunities in this fundamental problem.