HS anlog switch layout and Desing issue

[b4bb4ge]

I am designing a high speed switch network for my company and no one here has done any board layout I have this question:

Several of the 3 - 8GHz switches that are out there (GaAs Switches) have demo boards and all the demo boards are laid out using the CPW method.

I am wondering if it is possible to use a microstrip for this type of circuit (several switches on one board) or if you really need CPW to lay out this circuit properly?

If you need CPW do you not use a back side ground on your PCB or do you use the CPW Ground Method?

thanks for your help,
Zach

 

[spminn]

I have (unsuccessfully) used IC-based high-speed switches upto 3.5 GHz on board. I think microstrip simply does not work well in such cases. I had to put a few RF switches on one board and the results turned out to be terrible. The signals were getting attenuated by more than 15-20dB. Finally, we resorted to using RF switches from Mini-circuits, which are quite costly as compared to the IC-based switches, but did not require board (they were SMA switches).

 

[b4bb4ge]

thanks you would not know inside the mini-circuits switches if they were microstrip or CPW would you?