Fixed Attenuators: How to reduce port VSWR?

Problem:
If several 50 Ohm RF components are combined in series, the VSWR of each component adds together resulting in much higher output VSWR.  Often is the case when cabling together components such as power splitters, RF switches and directional couplers.

Solution:
Use a 50 Ohm fixed attenuator at the output port to mask the high series VSWR.

3.0:1 → reduced by 1dB attenuator → 2.318:1
3.0:1 → reduced by 2dB attenuator → 1.922:1
3.0:1 → reduced by 3dB attenuator → 1.669:1
3.0:1 → reduced by 4dB attenuator → 1.497:1
3.0:1 → reduced by 5dB attenuator → 1.376:1
3.0:1 → reduced by 6dB attenuator → 1.287:1
3.0:1 → reduced by 7dB attenuator → 1.222:1
3.0:1 → reduced by 8dB attenuator → 1.172:1
3.0:1 → reduced by 9dB attenuator → 1.134:1

Selection Chart:
The selection chart lists VSWR reduction levels for standard attenuator dB values.

Calculation:
The easy way to determine the fixed attenuator value needed to reduce your port VSWR is to think of it in terms of return loss.  Your port return loss is improved by double the fixed attenuator value.

-10dB return loss → 1dB attenuator → return loss reduced to -12dB
-10dB return loss → 2dB attenuator → return loss reduced to -14dB
-10dB return loss → 3dB attenuator → return loss reduced to -16dB
-10dB return loss → 4dB attenuator → return loss reduced to -18dB
-10dB return loss → 5dB attenuator → return loss reduced to -20dB