DC Block between antenna and a diode

Hello all,

I am working at 40 GHz and the circuit has a square patch antenna (40GHz) and a diode which is to be biased. Is it necessary to place a DC block between the diode and antenna. Even thou the antenna will not radiate DC , it can dissipate it?

I will measure the design without the cap but want to know the normal practise.

Thanks in advance.

If bias current through the diode is far higher then possible leakage from the patch to ground (think of contamination), an additional DC blocking capacitor isn't necessary.

When using a schottky diode, leakage current through diode will be factors higher then leakage current through RF laminate.

No, but there should be some series inductance between the top of the diode and the DC circuitry to keep the 40 GHz from going down the wrong path.