60-GHz 64- and 256-Element Dual-Polarized Dual-Beam Wafer-Scale Phased-Array Transceivers With Reticle-to-Reticle Stitching

Abstract

This article presents 60-GHz $2\times 64$ - and $2 \times 256$ -element dual-polarized dual-beam wafer-scale phased-array transceivers with integrated up/downconverters. The $2\times 64$ -element phased array is built as a single reticle and occupies $21\times21$ mm2. It is based on RF beamforming transmit/receive (TRX) channels with 5-bit phase and 9-bit gain control, dual nested 1:64 distribution networks with Wilkinson divider/combiners, line amplifiers (LAs), and dual up/downconverters with a shared local-oscillator (LO) multiplier chain. The differential on-chip antenna feeds are electromagnetically (EM) coupled to a high-efficiency quartz superstrate dipole antenna array placed $\lambda $ /2 apart in the horizontal and vertical directions. Four $2\times 64$ -element phased-array reticles are then bondwire-stitched in the intermediate-frequency (IF)/LO domain to form a $2\times 256$ -element phased-array super-reticle that occupies $42\times42$ mm2. The $2\times 64$ - and $2\times 256$ -element phased arrays scan to ±50° in the elevation ( $E$ -plane) and azimuth ( $H$ -plane) planes. The equivalent isotropically radiated power (EIRP) of the $2\times 64$ -element array is 37–38 dBm with a 3-dB bandwidth of 60–64 GHz, while that of the $2\times 256$ -element array is 42–44 dBm with a 3-dB bandwidth of 61–63 GHz per polarization. A communication link using the $2\times 64$ -element array is demonstrated with quadrature phase-shift keying (QPSK), 16-quadrature amplitude modulation (QAM), and 64-QAM waveforms, reaching 12–16-Gb/s data rates per polarization at 1.3 m. To the best of our knowledge, this article presents the first fully polarimetric scalable wafer-scale phased-array transceivers using simple reticle-to-reticle stitching, resulting in the state-of-the-art functionality and complexity on a single chip.