US 12,284,210 B2
Joint time-frequency measurement in optical communication
Bing Qi, Knoxville, TN (US)
Assigned to CISCO TECHNOLOGY, INC., San Jose, CA (US)
Filed by Cisco Technology, Inc., San Jose, CA (US)
Filed on Mar. 9, 2023, as Appl. No. 18/181,238.
Prior Publication US 2024/0305665 A1, Sep. 12, 2024
Int. Cl. H04L 9/40 (2022.01); H04B 10/075 (2013.01)
CPC H04L 63/1475 (2013.01) [H04B 10/075 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
receiving a photon signal jointly encoded in time and frequency as a time-frequency state;
separating the photon signal with a dispersive element to generate a plurality of frequency components;
delaying each corresponding frequency component of the plurality of frequency components by a corresponding time delay to generate a plurality of delayed frequency components;
combining the plurality of delayed frequency components to generate a frequency-separated signal; and
measuring the frequency-separated signal to determine the time-frequency state of the photon signal.