All-optical microwave filter has been a topic of interest for over two decades because of the many advantageous features such as large time-bandwidth product, wide tunability, high Q-factor, low loss, light weight, and immunity to electromagnetic interference offered by photonic devices. All-optical microwave photonic filter is a system used to implement microwave filtering in the optical domain, which can provide a large tunability and a high Q factor which are usually difficult to realize through conventional electronic methods. In addition, since the microwave signal is processed directly in the optical domain without additional optical-electrical and electrical-optical conversions, the photonic microwave filters are particularly suitable for applications such as optically controlled phased-array antennas, radio-over-fiber (RoF) systems, and other microwave-photonic links (MPLs). For these reasons, photonic microwave filters have attracted considerable interest for a few years.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.