Phase tuning beyond 180 degrees by injection-locked oscillators

A method to give phase tuning beyond 180 degrees using fundamental injection locking is presented in the paper. This is particularly useful for phased array antenna phase tuning which, previously, is limited to 180 degrees. It is shown that by phase shift accumulation in cascaded injection-locked oscillators, the phase tuning range can go beyond 180 degrees. Two injection-locked oscillators cascaded together are used to demonstrate the theoretical prediction, which theoretically can give 360 degrees phase shift. In addition, the effect on phase shift due to the locking regions is discussed.<>