In previous proposed system, Radio frequency signal was transmitted through RF system. But the system had some disadvantages like non coherence and system was not efficient. Hence to overcome these drawbacks, RF over Fiber system is proposed. In the proposed system, RF signal is the message signal which is used to modulate the optical signal that has to be transmitted over the optical cable. Mach–Zhender Modulators (MZMs) are used to convert the RF signal to optical signal when the light cannot directly modulate for higher speed, the Lithium Niobate, Mach-Zhender Modulator (LN-MZM) is used, Continuous Wave Laser diode is used as the source and PIN diode is used as optical detector. To transmit the optical signal Polarization-Maintaining optical fiber (PMF or PM fiber) is used, this transmitted signal is detected at receiver by optical detector .Hence in RF over fiber system are small in size, these are flexible and is a very low loss technology using intensity modulation to transmit RF signal.