US 11,852,864 B1
Serial arrayed waveguide grating
Mark Stephen, Catonsville, MD (US); Renan Moreira, Santa Barbara, CA (US); and Fabrizio Gambini, Santa Barbara, CA (US)
Assigned to United States of America as represented by the Administrator of NASA, Washington, DC (US)
Filed by United States of America as represented by the Administrator of NASA, Washington, DC (US)
Filed on Mar. 1, 2022, as Appl. No. 17/684,016.
Int. Cl. G02B 6/12 (2006.01); G02B 6/122 (2006.01)
CPC G02B 6/12011 (2013.01) [G02B 6/122 (2013.01); G02B 2006/1215 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An arrayed waveguide apparatus comprising:
a microwave-based spectrometer;
a high power distributed feedback (DFB) Laser modulated by an input microwave signal received by an antenna with an electro-optic modulator for generating a broadened optical signal;
a filter for separating the broadened optical signal into a plurality of 4.5-GHz bandwidth channels;
a plurality of optical delay lines connected in series between an input light source and an output of the apparatus for individually receiving the plurality of the 4.5 Ghz signals connected to a plurality of directional couplers; wherein the input signal from the input waveguide is split in two optical paths using a corresponding directional coupler through an integrated conducting path above each delay line to minimizes the thermal crosstalk between the input waveguide and the output waveguide which is connected in series between an input light source and an output of the apparatus.