Single Motion Gear System

Two Axes A and B interconnected by a gear box.
A-axis rotates in both directions between 300 a 20.000 rpms.
Axis B must always rotate in the same direction no matter which side Axis A rotates.
Axis B must rotate at the same speed as axis A rotates.
Develop the cx that allows these axes to rotate in this condition. Should be robust but not too big…