A 24–30-GHz 256-Element Dual-Polarized 5G Phased Array Using Fast On-Chip Beam Calculators and Magnetoelectric Dipole Antennas
Abstract
We present a 24–30-GHz 256-element dual-polarization transceiver (TRX) phased array based on a 16-element beamformer integrated circuit (BF-IC), 2-element frequency conversion integrated circuit (FC-IC), liquid crystal polymer (LCP)-based combiners and filters, and a tileable package with 64 embedded dual-polarized (dual-pol) antennas. The phased array presented in this work overcomes three key challenges in current 5G millimeter-wave (mmWave) antenna arrays: 1) it supports a dramatic increase in the number of supported fast-access beams; 2) it offers improved power efficiency; and 3) it provides a path to lower solution cost. 1) We enable fast switching among <inline-formula> <tex-math notation="LaTeX">$>$</tex-math> </inline-formula>30 000 beams—orders of magnitude improvement over prior work—by employing an on-chip beam calculator in the BF-IC, achieving 200-ns beam setup and 8-ns over-the-air (OTA)-switching time. 2) We enable a module-level transmitter (TX) mode peak power added efficiency (PAE) of 20% using a modular architecture that preserves power amplifier (PA) linearity and efficiency as well as receiver (RX) mode low noise amplifier (LNA) noise figure (NF). The module achieves Psat effective isotropically radiated power (EIRP) of 68.5 dBm and BF-IC NF <inline-formula> <tex-math notation="LaTeX">$<$</tex-math> </inline-formula>3.9 dB. 3) We lower the solution cost by enabling a wider steering range to reduce the number of phased arrays required in a sectorized coverage scheme, by reducing the IC and package area, and by avoiding calibration. The wider steering range is enabled by using an in-package magnetoelectric dipole antenna (for the first time in silicon-based phased arrays), resulting in steering over <inline-formula> <tex-math notation="LaTeX">$\pm$</tex-math> </inline-formula>70<inline-formula> <tex-math notation="LaTeX">$^\circ$</tex-math> </inline-formula> in H-and V-pol in both E-and H-planes without requiring any calibration. Moreover, the module achieves <inline-formula> <tex-math notation="LaTeX">$>$</tex-math> </inline-formula>20-dB cross-polarization isolation across the entire <inline-formula> <tex-math notation="LaTeX">$\pm$</tex-math> </inline-formula>70<inline-formula> <tex-math notation="LaTeX">$^\circ$</tex-math> </inline-formula> beam steering range.