Digital-Controlled High-Linearity Phase Shifter Using Vernier Ladder Network for Beyond 5G Phased Array Antenna

This paper presents linear phase shifter using Vernier ladder network. The linear phase control was achieved by vector modulator with pseudo-sine-cosine generator using folding circuits and proposed Vernier ladder network. The Vernier ladder network provides useful functions of digital control and linear phase control while having tolerance to PVT variations. A prototype phase shifter exhibits linear phase shift characteristics of over 360° at 2.5 GHz and 5 GHz. The measured RMS phase errors are 4.3° for 2.5 GHz and 4.6° for 5 GHz without any digital pre-calculation or calibration.