Also DWDM PON architectures are of high interest and are on the way to becoming commercially realized, the bandwidth can be substantially scaled up compared to common PON networks concepts. AWG based structures for MUX/DEMUX applications in WDM-PON networks are ideal, adapting perfectly to PON architectures, allowing cyclic character and are leveraging the state of the art PLC processing techniques. The recent progress of AWG design concepts for DWDM PON architectures and their athermal packaging techniques, now suitable for mass production in low cost manufacturing countries, are discussed. The state of the art reliability performance for industrial and in particular DWDM PON applications are demonstrated. AWG based DWDM PON network architectures are elaborated comparing other existing PON network concepts.
You may refer to this paper in this regard
http://ieeexplore.ieee.org/xpl/login.jsptp=&arnumber=4054038&url=http%3A%2F%2Fieeexplore.ieee.org%2Fstamp%2Fstamp.jsp%3Ftp%3D%26arnumbe