Antenna array pattern correlation and input type

When mutual coupling is present in an antenna array, the radiation patterns of the active elements as well as the pattern correlations depend on the representation of the input signal in terms of the input type. The pattern correlation is presented for different input types, i.e. for voltages, currents and voltage waves. It is shown for a microstrip array that a suitable choice of the reference plane of input voltages and currents can lead to a lower pattern correlation than for voltage waves.