Quarterwave balun on PCB

hi, I want to design a quarterwave balun on pcb. The one side of balun is connected through SMA to VNA port and the other side is connected to the GS probe with SMA, means its a module on PCB and the frequency of interest is 860mhz-960mhz. Can you help?

hi, I have dropped the idea of quarterwave balun because of its accuracy.