**4. Conclusion**

This book chapter reviews the application of multifunctional Semiconductor Optical Amplifier in microwave photonics optical communication links. The device shows proper performance during the theoretical and experimental study. The noise, the linearity, the bandwidth and the dispersion effect of the multifunctional SOA applied in an optical link are studied. SOAs are potential candidates for modulation and detection tasks in RoF systems as their capabilities for detection/modulation, and amplification at the same time. So, cost effective designs are possible only employing one device at the subscriber's unit. On the other hand, the multifunctional SOA can improve the performance of microwave photonic links thanks to its dispersion compensation function.
