Coupling effects in an integrated beam-forming transmitter

In an integrated beam-forming transmitter the proximity and common silicon substrate will inevitably lead to coupling between the different antenna phases. Chain matrix representation of individual stages is used to model the different coupling effects. Analysis shows that with realistic component values the produced beam shape becomes distorted due to the coupling. Predistorting the array control vector is proposed as a means to compensate for the coupling effects. Assuming that the coupling effects are known, it is possible to calculate the predistortion matrix in advance. The actual predistortion then takes only a single matrix multiplication per beam direction.