help me I swim

I want to design a double-balanced Gilbert cell in 180nm CMOS, but I do not know anything about the type of FET and the resistance value uses; help me I swim

Read this tutorial http://www.odyseus.nildram.co.uk/RFI...Cell_Mixer.pdf

how I polarizes Transistors:FET_Lo and FET_ RF ?
plise help me !