This paper presents a passive vector-modulated phase shifter (VMPS). The passive X-type attenuator consisting of digitally controlled transistor-array units is employed to perform the phase-invertible gain tuning, and thus enables phase shift in all four quadrants. The Wilkinson-like power combiner is utilized to sum up the quadrature signals and avoid impedance mismatches. Analysis proves that the proposed passive VMPS can provide consistent phase-shift performance for bidirectional operation. The proof-of-concept VMPS is implemented in 40-nm CMOS technology and occupies a core chip area of 0.15 mm2. Measured results prove that it can provide consistent bidirectional 6-bit phase-shift operation, with accurate phase tuning (i.e., RMS phase error <; 24°) and low gain error (i.e., ±0.6 dB) over the whole 70-90 GHz band.

Large-scale millimeter-wave (mm-Wave) integrated phased array is the key technology to enable broadband 5G and satellite communications. This paper details the design considerations, challenges and trade-offs of mm-Wave integrated phased arrays based on bulk CMOS and multi-layer hybrid PCB technologies. Both technologies attain high yield and low cost for mass production. Important beamforming building blocks are addressed and compared in detail. Demonstrators of integrated phased arrays are presented from circuit to board levels. The 1024- and 4096-element integrated phased arrays achieve the EIRP of 72.5 and 84.0 dBm respectively. Finally, relevant phased-array transceivers and antennas from the recent literature are discussed.

In this paper, system considerations and circuit implementations for 5G millimeter-wave (mm-Wave) phased-array transceiver are presented. High data-rate and medium-range communications pose challenges for the design of phased-array transceiver circuits operating at the mm-Wave band. A possible solution is that the core chip for digital, mixed-signal and RF processing blocks are integrated in advanced CMOS, while power amplifier (PA), low-noise amplifier (LNA) and RF switch are implemented in III-V technologies (i.e., GaAs or GaN). To show the feasibility of such system architecture, key building blocks include high power amplifier (HPA), broadband LNA, amplitude-invariant phase shifter and phase-invariant variable gain amplifier (VGA) are reviewed. The proposed techniques make the mm-Wave phased-array transceiver systems suitable for 5G fixed wireless access (FWA) applications.