Interference Matrix Definition

An interference matrix is a way to illustrate the cross-coupling between ports of a multiport system. Example applications are antenna arrays, feed networks or power dividers.

The off-diagonal components of a multiport S-parameter matrix contain all the required information to create an interference matrix. The user sets the maximum and minimum thresholds and the colours indicate if the cross-coupling between the ports are within the acceptable range. The rows represent the transmitting ports and the columns the receiving ports. Green boxes indicate that interference between the ports is below the threshold minimum. The diagonal elements contain no cross-coupling information since it is the power measured at the port from exciting the port itself.

Figure 1. Example of an interference matrix with a threshold range between -15 and -20 dB.