A Sub-6-GHz 5G New Radio RF Transceiver Supporting EN-DC With 3.15-Gb/s DL and 1.27-Gb/s UL in 14-nm FinFET CMOS

Abstract

The world’s first single-chip RF transceiver to support 5G sub-6-GHz new radio (NR) and long-term evolution (LTE) E-UTRA New Radio-Dual Connectivity (EN-DC) in 14-nm FinFET CMOS technology is presented. The single-chip transceiver integrates identical primary and diversity receivers (RXs) with seven pipelines for supporting four inter-band carrier aggregation (CA) with three 4 $\times $ 4 MIMO, two independent transmitter (TX) chains, eight frequency synthesizers for RX and TX, and on-chip digitally controlled crystal oscillator (DCXO) to reduce the phase noise and bill of material (BOM) cost. The receiver features 12 single-ended low-noise amplifiers (LNAs) with wideband characteristics. With the help of the proposed pipeline structure and frequency-band switchable transformer, the die size can be reduced despite covering the whole frequency range from 2G to sub-6-GHz 5G NR. It achieves the noise figure (NF) from 6.5 to 9.3 dB, +3-dBm out-of-band (OOB) IIP3, more than +70-dBm OOB IIP2 after calibration. For the transmitter, low RX-band noise and harmonic suppression technique are applied to support surface acoustic wave (SAW)-less architecture, and the bandwidth control of the baseband filter is implemented for the digital pre-distortion (DPD) operation of 100-MHz BW in NR transmit data. The measured error vector magnitudes (EVMs) in 4G and 5G bands of n79 are −39.5 dB at +4-dBm output power and −33.9 dB at +3.06-dBm output power, respectively, and the measured RX-band noise of 2G is −163 dBc at 20-MHz offset. The RX consumes 18 mW at LTE 1-CA mode and the TX consumes 350 mW at n79.