The objectives of this book is to investigate the performance evaluation & optimization of WDM RoF link. In this book, WDM Radio over Fiber (RoF) system is introduced, which is one of the enabling technologies for 3G and beyond. The performance evaluation of WDM Radio over Fiber transmission system (RoF), based on various performance metrics such as Q-factor, BER and eye opening has been made at various data rates. The integration of the two systems is responding to the demands for high data rate applications and reasonable mobility for broadband communication. This work deals with the modeling, realization and characterization of WDM RoF systems providing data rates within the 100 to 3000 Mbps range. It has been investigated that system provides optimum results at data rate of 500 Mbps. The system is of low cost and can be scaled to higher data rates.