We design and implement a cost-effective and compact 100-Gb/s (2 × 50 Gb/s) PAM-4 receiver optical sub-assembly (ROSA) by using a TOcan package instead of an - expensive box-type package. It consists of an optical demultiplexer, two PIN-PDs and a 2-channel linear. The Pulse Amplitude Modulation 4-level (PAM4) optical transceiver market is poised for substantial expansion, driven by escalating demand for high-bandwidth, long-haul data transmission across critical applications. Key growth catalysts include the rapid proliferation of cloud computing, the. We distinguish the PAM4 bit rate from its symbol rate, refer ling, but the formal description is 2-level pulse amplitude modulation, or PAM2. Since PAM4 signal do not return-to-zero after each symbol, they are also an NRZ signaling scheme. In this paper, we'll refer to the two schemes as PAM2-NRZ. Optical Network Research Group, Electronics and Telecommunications Research Institute, 218 Gajeongno, Yuseonggu, Daejeo, 34129, South Korea *skkang35@etri. So what is PAM4 modulation and how is it transforming optical networking?high-reliability Dynamic Connectivity Platform for long-distance, high bandwidth applications. It is composed of. Operating Principle, OSNR Sensitivity, DSP Requirements, and the Boundary Between PAM4 and Coherent QAM in Modern Data Centre Networks The relentless growth of data centre traffic, driven by cloud computing, artificial intelligence workloads, and high-performance computing, has steadily eroded the.