Compact K-Band Lange Coupler Based 2-Bit RF MEMS Reflection-Type Phase Shifter

Lange Coupler and low-loss shunt DC contact Microelectromechanical System (MEMS) switches have been implemented which in turn reduces the loss of the reflection-type MEMS phase shifter (RTPS) at K-band. ON-OFF mechanism of respective switches in both arms, changes the length of the short-ended stubs which introduces the respective phase changes double of the phase given by the path length. Simulated work of this 2-bit (135°) RTPS shows an average insertion loss of less than 1.1 dB with return loss better than 13.5 dB from 15 to 25 GHZ. The designed phase shifter occupies small area of 1.76 mm × 2.45 mm. The measured maximum phase error between 135° and 90° phase states is 1.15° about 20 GHz frequency.