Can any one talk something about Butler Matrix design

Can any one talk something about Butler Matrix design, I'am wondering how to design a 4*4 Butler with unequal output port.

I once looked into this (for eight by eight arrays) for the purpose of tapering the array for reducing sidelobes. The problem is that the four input ports will then produce outputs with different antenna weightings. Some inputs will have low sidelobes, some will have higher ones.

One way is to have attenuators in the outputs but this ruins the array gain.

This is not to say that someone else cannot solve this problem.

Attached here examp.

pl

plasma

thank you