Advantages of Radio over Fiber | disadvantages of Radio over Fiber
This page covers advantages and disadvantages of Radio over Fiber (RoF). It mentions benefits or advantages of Radio over Fiber and drawbacks or disadvantages of Radio over Fiber.
What is Radio Frequency over Fiber (RoF)?
RoF is the short form of Radio over Fiber. There is adundance of data over the internet. It requires huge bandwidth to support increased data requirements without much of the interference to achieve end to end data integrity. Radio over Fiber system fulfils these requirements.
The figure depicts RoF (Radio over fiber) system block diagram. CO (Central Office)/CS (Control Station) units are used for signal generation. Appropriate modulation/signal processing is employed at CO/CS to generate baseband signal. Here RF signal is transferred with the help of fiber link. The signal is received by BS (Base Station). At the base station E/O and O/E conversion have been carried out. "E" stands for Electrial and "O" stands for Optical. The communication between BSU and Mobile wireless units is carried by Radio frequency waves using antennas. Base Station Unit communicate with CS using optical signal.
Benefits or advantages of Radio over Fiber (RoF)
Following are the benefits or advantages of Radio over Fiber (RoF):
➨It uses optical fiber cables to transmit data in the wireless network. Optical fiber uses carrier frequencies in 200 THz range in contrast to microwave with upto 1 GHz. The huge bandwidth supported by fiber makes it best option to carry radio frequency waves. Fiber uses WDM and OTDM techniques to support increased bandwidth.
➨Optical fiber offers very low attenuation. In RoF system, they are used between CO and BS to leverage benefits compare to free space and copper cable transmission. RF signal transmission in free space leads to absorption and reflection of RF signals. Moreover RF signal distribution in electrical form has many drawbacks such as absorption, reflection, impedance rise etc. Hence RoF offers low attenuation loss.
➨RoF system is easy to install and maintain.
➨In RoF, RF signal is carried by optical fibers which offer immunity against EM (electromagnetic) interference. This property provides security and privacy. As a result integrity of information is preserved since eavesdropping is not possible.
➨Switching and modulation equipments used at CS offer dynamic allocation of capacity based on demand.
➨Complex equipments are used at CS side to reduce power consumption. Moreover BSs are switched to passive mode to save power.
Drawbacks or disadvantages of Radio over Fiber (RoF)
Following are the drawbacks or disadvantages of Radio over Fiber (RoF):
➨RoF is analog transmission system and hence it is prone to signal impairments such as noise and distortion.
➨Nonlinear effects such as dispersion is possible in optical fiber.
➨It requires expensive special tools for maintenance and repair. Moreover initial cost of installation is also higher.
➨It is difficult to splice than wires at start/end joints. Moreover it requires expensive connectors and interfacing tools.
➨E/O and O/E conversions are required in RoF system. This adds complexity and increases cost of the RoF system.
Conclusion: Some method or modulation technique can be developed to minimise effects of impairments and dispersion observed in optical fiber. Hence RoF can be used as reliable system for users to achieve communication with minimal degradation of wireless range.