Patent ID: 6956993

Claim:
A method of increasing the transmission efficiency of a P×Q arrayed waveguide grating (AWG) comprising: arranging the spacing and position of the P input ports and the Q output ports of said arrayed waveguide grating so as to increase a signal transmission coefficient from each of the P input ports to the Q output ports, wherein said arranging comprises: initially positioning a first input port near the center of the AWG; initially positioning the Q output ports at positions defined by images of wavelengths dispersed by the first input port; initially positioning the remaining P−1 input ports of said AWG at positions defined by images of wavelengths dispersed by a substantially central output port of said AWG; determining an angular spread, Δ q , for each of the Q output ports, where Δ q is the angular spread of the images of wavelengths expected to converge on each of the output ports; determining a final position for the P input ports by varying the initial position of the input ports until a value of Δ MAX is minimized, where Δ MAX is a maximum one of the determined angular spreads, Δ q , for each of the output ports; and repositioning the output ports of said AWG such that each output port is positioned in substantially the center of its respective final angular spread, Δ q , wherein said respective final angular spreads are defined by the images of the wavelengths dispersed by the finally positioned input ports.