Inverse methods for branched ducts and transmission lines

Whereas time-domain approaches to one-dimensional inverse scattering can be said to be well understood, many conceptual difficulties remain for more than one dimension, except in situations where elementary echo-location ideas apply. Algorithms appropriate for inverse problems involving branched ducts and transmission lines are presented here; such problems can be thought of as being intermediate in difficulty between one-dimensional and many-dimensional problems. Data processing procedures that can handle noisy measurements are described. The effects of finite signal bandwidth are taken into account. Results are presented of the inversion of ideal data (generated in a computer) and data derived from actual measurements.