Linearized Electro-Optical Modulation for Analog Radio over Fiber

Intermodulation distortion (IMD) in Analog Radio-over-Fiber (a-RoF) poses a severe limitation to achievable error-free transmission. In this work, an optical feed-forward linearization scheme is presented and compared to an electrical pre-distortion solution. Both techniques show identical performance for intermodulation compensation of neighboring frequencies. The former suits wideband multi-carrier transmission better because it does not present limited operational bandwidth. Proof-of-concept experiments for reducing intermodulation and distortions are offered. A 5-dB improvement in the Error Vector Magnitude (EVM) distortion floor level is achieved. Trade-off between compensating for second and third harmonics was verified. Results indicate the solution allows maximal exploitation in a-RoF capacity.