Due to low intermodal dispersion, single-mode fiber can support longer transmission distances than multi-mode fibers, and can support transmission distances of more than 5km from 100Mbps Ethernet to 1G Gigabit networks. At present, single-mode optical fiber is still the mainstream application of optical fiber transmission. Follow the FIBCONET in this article to learn more.
Single Mode Fiber (SMF) is an optical fiber that can only transmit one mode in its operating wavelength. Due to the thin core of the fibre (approximately 10 μm) and the step-like distribution of the refractive index, when the normalised frequency V parameter is <2.4, theoretically, only single mode transmission is possible. In addition, SMF has no multimode dispersion, not only is the transmission bandwidth wider than multimode fibres, plus SMF material dispersion and structural dispersion add up to cancel, its synthetic properties form exactly zero dispersion characteristics, so that the transmission bandwidth is even broader. It is suitable for long distance, high capacity fiber optic communication systems, fiber optic local area networks and various fiber optic sensors.
Multimode fiber (MUlti Mode Fiber, MMF) is a fiber that can propagate more than one mode in the operating wavelength. With a core diameter of 50 μm, the transmission bandwidth is mainly governed by mode dispersion compared to SMF due to the transmission of up to several hundred modes, resulting in time delays and broadening of optical pulses after long distances. It is only suitable for smaller capacity fibre optic communications.
Then in addition to the differences in transmission modes, single-mode and multimode fibres also have differences in fibre diameter, protective jacket colour, transmission light source, transmission distance, bandwidth, price and application scenarios. These differences also determine that single-mode fibres are the mainstream application for fiber optic transmission, as they respond to the development of laser technology and people’s demand for long-distance, high-information communications.
But will single-mode fiber remain mainstream? The answer is not necessarily according to the latest market news, with the booming development of communication services, the global network traffic has increased sharply, the development of common single-core single-mode optical fiber transmission is limited in the next few years, the contradiction between the weak growth of optical network and the high bandwidth demand of the market is becoming increasingly sharp, becoming an important issue to be urgently solved in the optical communication industry .In order to solve the problem of optical communication capacity expansion in the future, the accepted technical solution to improve single-fiber capacity is to use space division multiplexing technology. Multi-core fiber 、multi-mode fiber or multi-core multi-mode fiber is the inevitable development trend of optical communication transmission