基于阵列波导光栅的单纤三重波分复用器

A Novel Triplexer Design Based on Arrayed Waveguide Grating

利用阵列波导光栅实现单纤三重波分复用器是一种具有很多优点的方法.ITU G.983标准规定了无源光网络的三个波长为1310,1490和1550nm,由于这三个波长的间距相差很大,光谱范围也大,用普通的AWG设计方法不能达到理想的效果.文中提出了一种基于阵列波导光栅的单纤三重波分复用器的新型设计,利用衍射光栅的频谱周期性,使离第二、三波长较远的第一波长工作在不同的衍射级次,并将第一波长映射到与第二、三波长形成几乎等间距信道的第四波长,从而减小了对光栅自由光谱范围的要求,同时使对应这三个工作信道的输入/输出波导几乎等间距,解决了传统设计方法导致的衍射级次小、器件尺寸大、制作困难等问题.

An arrayed waveguide grating （AWG） based triplexer has many advantages including small size and low cost. The commonly used wavelengths in passive optical network （PON） are 1310nm, 1490nm and 1550nm, according to ITU G. 983 standard. Because of the wide spectral range and very unequal channel spacings, a conventional AWG design cannot produce a satisfactory result. In this paper, a novel triplexer design based on AWG is presented. The spectral periodicity of the grating is utilized in the design so that the first wavelength works at a different diffraction order,and it is mapped to a wavelength that is approximately in the middle of the second and third wavelength channels. This results in a reduced free spectral range （FSR） requirement and almost equal distances between the input/output waveguides. Consequently, the AWG can operate at a higher diffraction order with a smaller device size,compared to the one designed by conventional methods.