Furukawa Electric Review No.56An Ultra-Compact VCSEL-based Transceiver for Co-Packaged Optics and Testing Station Employing a High-Density Electrically Pluggable Interface

Wataru Yoshida, Kazuya Nagashima, Kensho Nishizaki, Sho Yoneyama, Hideyuki Nasu

This paper describes design and characteristics of a Vertical Cavity Surface Emitting Laser (VCSEL)-based transceiver for Co-Packaged Optics under the National Institute of Information and Communications Technology (NICT) Beyond 5G BRIGHTEN project. To decrease the mechanical size, we adopt the record narrowest 0.3-mm pitch Land Grid Array (LGA) for the electrical interface of the transceiver. Consequently, a footprint is as narrow as 7.7 mm × 15.9 mm. We also design and fabricate an electrical pluggable interface for 0.3-mm pitch LGA. To characterize the electrical pluggable interface, we designed and fabricated a testing station which is employing the electrical pluggable interface. A 3-dB bandwidth of the testing station is as wide as ≧ 14 GHz, which is equivalent to the Nyquist frequency of 28 Gbaud operation. We attach the VCSEL transceiver to the testing station and evaluate the optical link characteristics. When operating 8 channel simultaneously with 56-Gb/s PAM4 signal, we achieve enough bit error rate to build a 400-Gb/s optical link.