Macrobending Loss Analysis of Singlemode-Multimode-Singlemode (SMS) Optical Fiber Structures on Variation of Macro Bend and Multimode

This research aims to (1) analyze the effect of Singlemode Multimode Singlemode (SMS) optical fiber on the variation of diameter, the number of coils, wavelength, and length of multimode at wavelengths of 1310 nm and 1550 nm, and (2) compare the losses of SMS optical fiber structure with and without macrobending. The optical fibers use singlemode G.652D type and multimode OM1 type. The macrobending variation model uses helical and S-shaped with a variation of 1-5 coils. In the helical, the radius of curvature constant (R=10 mm), the diameter of coils obtains from the variation of the helical radius, r=5 mm-9 mm. Whereas, for the S-shaped model variation of radius are, r=3 mm-12.5 mm. The total length of the SMS structure is 240 cm, with variations in the length of the multimode fiber 80 cm, 90 cm, and 100 cm relative to the length of singlemode fiber. The results showed that the smaller indentation diameter (1 cm and 0.6 cm) and the larger number of turns (5 turns) gave greater losses. Furthermore, multimode fiber with a length of 100 cm tends to have high light intensity. It was also found that the SMS structure with macrobending provides greater losses that the straight one. At the indentation diameter of 1 cm and 1.5 cm, the S-shaped model gives higher losses than the helical model at wavelengths of 1310 nm and 1550 nm.