Capacitive cross coupled injection locked frequency dividers ILFDs have the merits of low power and wide locking range This book introduces the design of wide locking range ILFDs based on capacitive cross coupled oscillators and using multi resonance RLC resonator The merits are shown experimentally and by simulation Many designed divide by 2 and divide by 3 ILFD examples using RLC capacitive cross coupled oscillators are used to verify the usefulness of the design method The design method is also a sensitive technique to find the distributed effect of on chip inductors