Abstract:In response to the application requirements of phase-shifting arrays in massive MIMO and wireless backhaul systems for the fifth-generation mobile communications, in this paper the topology of the reflection-type phase shifter ( RTPS ) is compared and analyzed, the design method of the four-element dual-adjustable (FEDA) load topology and the adjustment method of phase conversion are proposed, and the influence factors of phase shift step and insertion loss are analyzed. Moreover, the digital tunable capacitor (DTC) is used for RTPS tuning design. The experimental results show that the RTPS in this paper has a measured phase shift range greater than 360°, a phase shift step less than 12°, an insertion loss less than 1. 8 dB and the size only 10 mm× 8 mm in the full frequency range of 4. 4~ 5. 0 GHz. In summary, this RTPS has the advantages of low insertion loss, miniaturization, large bandwidth, high precision and easy control.