A Demultiplexing Scheme Using an Arrayed- Waveguide Grating for a Dwdm Mm-wave Fiber- Radio System by Optical Frequency Interleaving

Introduction Recent progress in transmission capacity of dense wavelength-division multiplexed (DWDM) signals in a trunk optical fiber line now allows transmission of data beyond 10 Tbit/s over more than 100 km [1], [2]. The DWDM technology has to be applied to future millimeter-wave fiber-radio systems in order to take the capability to deal with the large amount of data capacity. There have been several reports to increase the spectral efficienty of such DWDM fiber-radio systems [3], [4]. Very recently, we proposed to use optical frequency interleaving to realize a DWDM mm-wave fiber-radio system. In this paper, we propose a possible demultiplexing scheme for the system. The scheme consists of a Fabry-Perot etalon, an optical circulator and a 2 x N arrayed-waveguide grating, which is designed to steer the input signals with the frequency difference equals to the millimeter-wave carrier frequency into the same output waveguide.