Single-mode and Multimode Optical Fibers: Theoretical Comparison and Performance Analysis

This research presents a theoretical and numerical comparison of single-mode and multimode optical fibers to evaluate their transmission performance under different operating conditions. The study is based on the fundamental equations of optical propagation, including numerical aperture, normalized frequency, number of guided modes, attenuation, dispersion, and maximum transmission distance. A MATLAB-based simulation is used to analyze a G.652 single-mode fiber operating at 1310 and 1550 nm and a 50/125 µm OM3 multimode fiber operating at 850 nm. The results show that, at a data rate of 10 Gb/s, the OM3 multimode fiber achieves a maximum transmission distance of approximately 0.28 km, compared with 31 km at 1310 nm and 36 km at 1550 nm for the single-mode fiber. The analysis also demonstrates that attenuation and dispersion play complementary roles in limiting transmission performance, depending on the operating wavelength and data rate. While single-mode fibers are better suited for long-distance and high-capacity communication systems, multimode fibers remain advantageous for short-distance links where installation cost and connection simplicity are important. These findings provide a quantitative basis for selecting the appropriate optical fiber architecture according to transmission requirements.