Switched power supply effect on PA

Due to power supply restrains, I have to raise the input voltage level (DC) to power a PA that's gonna be working in the UHF range.
What precautions should I look into before attempting this, such as maybe harmonics, some special kind of filter at the output, separated grounds, or stuff like that?
I know some of the theory, but don't have much practice in this area, so I don't know what to look for and what to avoid when mixing switched power supplies and UHF.
Any tips, references, links, etc. is welcome :D

The switching frequency of the power supply could affect the modulation of the transmitted signal. So, good filtering is required.
Also if the PA works in burst mode, some switching supplies requires careful design when intermittent high current load is present at the output.

The operation mode will be continuous wave, so there wont be intermittent high currents. As for the good filtering, do you have any example or reference design?
- Thanks