Hi @cgbottenfield

Generally AWG devices serve as multiplexers, demultiplexers, filters, and add-drop

devices in optical WDM and DWDM applications. Figure 1 shows a schematic

representation of the MxN AWG. The device consists of two concave slab waveguide

star couplers (or free propagation zones/ranges, FSZ), connected by a dispersive

waveguide array with the equal length difference between adjacent array waveguides.

Generally, there are two kinds of AWG: 1xN (M=1) and NxN (M=N). The number of the wavelength channels N is selected with the exponent of 2 such as 16, 32, 64, and 128.

The number of the array waveguides P is not a dominant parameter in the AWG design

because the Δλ and N do not depend on it. Generally, P is selected so that the number of

array waveguides is sufficient to make the numerical aperture (NA), in which they form a

greater number than the input/output waveguides, such that almost all the light diffracted

into the free space region is collected by the array aperture. As a general rule, this number

should be bigger than four times the number of wavelength channels.

For example, you can have an AWG with M=1 (number of input ports), N=16 (number of output ports), P = 60 (number of array waveguides).

Best Regards

Konstantinos