A 25.78-Gbit/s × 4-ch Active Optical Cable with Ultra-Compact Form Factor for High-Density Optical Interconnects

A 25.78-Gbit/s × 4-ch active optical cable (AOC) with an ultra-compact form factor is proposed. The size of the proposed AOC is 5.2 cm3, which is 55% smaller than the standard form factor of Quad Small Form-factor Pluggable (QSFP28), and 45% smaller than that of Micro Quad Small Form-factor Pluggable (μQSFP). As a result of utilizing a high-efficiency heat-dissipation structure and optimizing signal transmission lines and ground vias, the proposed AOC achieves high-heat dissipation and low-crosstalk characteristics. Furthermore, the proposed AOC demonstrated 25.78-Gbit/s error-free optical transmission over a 100-m Optical Multimode 3 (OM3) multimode fiber under all-channels (4-ch) operation and case temperature (Tc) of 70 ◦C.