In the launch window for the transient solver, you can set an option for 'Simultaneous excitation' instead of 'All ports (all modes)'. Through this, you can specify the powers and phases to be used for each port.
Another option is to solve for each port excited separately, and then use the 'Combine 3D results' post-processing template.
In the launch window for the transient solver, option for 'Simultaneous excitation' instead of 'All ports (all modes)'. we can specify the powers and phases to be used for each port at just one frequency and I want it on broadband of frequency. and to use 'Combine 3D results', is it necessarily to excited each port separately at each frequency as well ???