Monolithically Integrated Optical Phased Array for Optical Wireless Communication

• Published in: Journal of lightwave technology 2024-12, Vol.42 (23), p.8181-8190
• Main Authors: Kim, Youngin, Kulmer, Laurenz, Keller, Killian, Park, Jeongsoo, Abdelmagid, Basem Abdelaziz, Choi, Kyung-Sik, Lee, Dongwon, Liu, Yuqi, Leuthold, Juerg, Wang, Hua
• Format: Article
• Language: English
• Subjects: Beam steering; Broadband antennas; CMOS; High-speed optical techniques; Monolithic integration; Optical modulation; optical phased array (OPA); Optical transmitters; optical wireless communication (OWC); Phase shifters; Phased arrays; silicon photonics; silicon-on-insulator (SOI); Wireless communication; wireless data transmission
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2024.3425521

This paper presents a compact and power efficient one-chip optical phased array (OPA) transmitter (TX) for optical wireless communication (OWC). A traveling-wave-electrode Mach-Zehnder modulator (TWE-MZM) and mm-Wave driver, which would traditionally be implemented by bulky off-the-shelf components, are monolithically integrated with a silicon-based 1 × 64 OPA onto a single chip, reducing an active area of the entire system down to 6.4 mm 2 . Moreover, a co-design and integration of TWE-MZM and mm-Wave driver largely minimizes the parasitics and mismatches of an interface between the TWE and mm-Wave driver. The 64-element optical antenna achieves beam divergence of 0.77° and 4.23° over transversal and longitudinal direction, respectively. The two-sided beam-steering angles of the array antenna in transversal and longitudinal direction are ±14.3° and 6.1°, respectively, while the side-lobe suppression ratio is 7.81 dB. The co-integrated TWE-MZM and driver support a measured data rate up to 15 Gbps and consume 210 mW. To the best of our knowledge, our proposed electronic-photonic integrated circuit is the first OWC-application OPA TX, which monolithically integrates TWE-MZM, CMOS driver, and OPA all in one-chip.