Design of DC bias network in GHz range

Hi, everyone. I am wondering how to design the DC bias network for varactor in GHz range. I saw many literatures using the radial stub with a very narrow microstrip line as the bias pads. Anyone has some recommendation references of this type of DC bias network and any other topologies? Thanks.

How many GHz and bandwidth are we talking about here? Did you consider a simple 0603 10-47k resistor?

Hi, rfmw.
The desired frequency is about 2GHz.
Can you give me some layout/circuit example for using the 0603 resistor?

I think the most difficult part is the RF choke for the DC bias, I tried the 0804 440nH inductor as the RF choke, but it seems the isolation between the DC feed to the RF port is still too low.

If your application is sufficiently narrowband, you can use quarter wave lines
to form a bias tee. See the example given in http://www.microwaves101.com/encyclo...ve.cfm#biastee

One quarter wave line is used as an RF choke to keep RF out of the bias network.
The other line prevents the bias network from loading the RF signal.