ADC/DACs Antenna Array 1 Antenna Array 2 48 FALL 2021 IEEE SOLID-STATE CIRCUITS MAGAZINE Stream LNA Phase Shifter PA Amplifier Tx IF 1-4 5-8 13-16 9-12 (a) LNA Phase Shifter PA Amplifier Tx IF 1-4 5-8 13-16 9-12 Tx RF Mixer ×5 ×4 ÷2 5−6 GHz Fractional-N PLL (b) (c) I Q 90/270° ÷2 I Q 90/270° Tx I/Q Mixer 0/180° Amplifier Rx RF Mixer Stream 2 Rx IF Rx I/Q Mixer 0/180° Tx RF Mixer ×5 ×4 ÷ 2 I Q 90/270° ÷ 2 I Q 90/270° Tx I/Q Mixer 0/180° Amplifier Rx RF Mixer 1 Rx IF 0/180° Rx I/Q Mixer FIGURE 5: A 5G NR base station consists of RF/IF transceiver chipsets with dual-stream antenna arrays [8]. (a) Phased-array IC 1. (b) Phased-array IC 2. (c) A single-chip, dual-stream IF transceiver. ADC: analog-to-digital converter; DAC: digital-to-analog converter.