Issue regarding distance between a stripline and power via-hole

Hello everyone,
in our project there is a stripline close to a via-hole trought which we bring a 3.3V voltage to board.
The via-hole is 3.5 mm far from stripline.
On stripline there is an analogue carrier at 390 MHz that has a rms power minor than 0 dBm.

Can the distance between stripline and via create a problematic cross-talk?

Best regards.

Antonio

3.5mm is quite far already. But you can still place a GND via between to further reduce crosstalk.

You don't state the impedance of your stripline, but assuming it is 50 ohms, make the power line as high impedance as is practical, ie, make it thick enough to carry the proper current, but thin enough to be higher impedance. Strive to make this impedance at least 200 ohms at 390MHz. Where the via holes pokes to an exposed layer, placing bypass caps of 220pF and 0.1uF to ground will shunt out most of the crosstalk.

thats 140 mils. THAT is pretty far, AND your frequency is very low. I would say there is probably -70 dB of coupling to that via hole.