A new method for the reduction of crosstalk and echo in multiconductor interconnections

Crosstalk and echo can be reduced in multiconductor interconnections, using (truly) matched terminations and a different modal variable for each transmission channel. We first study a conventional technique for reducing reflections, using grounded linear two-terminal circuit elements. Using the concepts of modal voltages and modal currents, we define a new method for the reduction of crosstalk and echo, which involves specific terminations, specific transmitting circuits to send signals, and specific receiving circuits to receive signals. We establish the design equations and show that the new method is related to a particular choice of eigenvectors, called associated eigenvectors. Simulations of two examples of implementation of this method confirm that it provides reduced crosstalk and echo. We also discuss the implementation of the new method with an interconnection having identical propagation constants for all modes. Finally, we compare the new method with a different concept based on modal variables and unspecified terminations.