IP Library › Granted Patent US 12,706,678
Granted Patent B2
US 12,706,678 · App. 18/427,682 · Granted Aug 11, 2026

Optical signal processing

Inventors: Olga I Vassilieva (Plano, TX); Inwoong Kim (Allen, TX); Paparao Palacharla (Richardson, TX)
Assignee: 1FINITY Inc.
H04B10/6971H04J14/02762
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Quick Facts
Patent No.
US 12,706,678
App. No.
18/427,682
Filed
Jan 30, 2024
Granted
Aug 11, 2026
Kind
B2
Art Unit
2634
USPC
398/26
Abstract

Operations include generating an optical signal having a plurality of subcarriers. The operations further include performing a signal-to-noise ratio (SNR) equalization process with respect to the plurality of subcarriers based on an SNR factor associated with propagation of the optical signal along an optical signal path, the SNR equalization process including respectively adjusting, for one or more individual subcarriers of the plurality of subcarriers, one or more of: a forward-error-correction rate respectively corresponding to the one or more individual subcarriers; or a symbol rate respectively corresponding to the one or more individual subcarriers.

Claims (33)

1 . A system comprising:

an optical transponder configured to perform operations, the operations including:

generating an optical signal including a plurality of subcarriers; and

performing a signal-to-noise ratio (SNR) equalization process with respect to the plurality of subcarriers based on an SNR factor associated with propagation of the optical signal along an optical signal path, the SNR equalization process including respectively adjusting, for one or more individual subcarriers of the plurality of subcarriers:

a forward-error-correction (FEC) rate respectively corresponding to the one or more individual subcarriers; and

a symbol rate respectively corresponding to the one or more individual subcarriers,

wherein the symbol rate and the FEC rate are balanced to preserve a data rate for each individual subcarrier of the one or more individual subcarriers.

2 . The system of claim 1 , wherein the optical transponder is further configured to adjust a symbol rate of the one or more individual subcarriers.

3 . The system of claim 1 , wherein the optical transponder is further configured to adjust a bandwidth of the one or more individual subcarriers without changing an overall bandwidth of the optical signal.

4 . The system of claim 1 , wherein the optical transponder is further configured to adjust an overall bandwidth of the optical signal by adjusting a bandwidth of the one or more individual subcarriers.

5 . The system of claim 1 , wherein the one or more individual subcarriers is an edge subcarrier of the optical signal and the optical transponder is configured to adjust the one or more individual subcarriers to reduce an impact of passband narrowing.

6 . The system of claim 1 , wherein the one or more individual subcarriers is a center subcarrier of the optical signal and the optical transponder is configured to adjust the one or more individual subcarriers to reduce an impact of non-linear interference.

7 . A method comprising:

generating an optical signal including a plurality of subcarriers; and

performing a signal-to-noise ratio (SNR) equalization process with respect to the plurality of subcarriers based on an SNR factor associated with propagation of the optical signal along an optical signal path, the SNR equalization process including respectively adjusting, for one or more individual subcarriers of the plurality of subcarriers:

a forward-error-correction (FEC) rate respectively corresponding to the one or more individual subcarriers; and

a symbol rate respectively corresponding to the one or more individual subcarriers,

wherein the symbol rate and the FEC rate are balanced to preserve a data rate for each individual subcarrier of the one or more individual subcarriers.

8 . The method of claim 7 , further comprising increasing a symbol rate of the one or more individual subcarriers.

9 . The method of claim 7 , further comprising adjusting a bandwidth of the one or more individual subcarriers without changing an overall bandwidth of the optical signal.

10 . The method of claim 7 , further comprising adjusting an overall bandwidth of the optical signal by adjusting a bandwidth of the one or more individual subcarriers.

11 . The method of claim 7 , wherein the optical signal path is a metro signal path having passband narrowing affecting an edge subcarrier of the one or more individual subcarriers.

12 . The method of claim 7 , wherein the optical signal path is a long-haul path having non-linear interference affecting a center subcarrier of the one or more individual subcarriers.

13 . A non-transitory computer-readable storage medium configured to store instruction that, in response to being executed, causes a system to perform operations, the operations comprising:

generating an optical signal including a plurality of subcarriers; and

performing a signal-to-noise ratio (SNR) equalization process with respect to the plurality of subcarriers based on an SNR factor associated with propagation of the optical signal along an optical signal path, the SNR equalization process including respectively adjusting, for one or more individual subcarriers of the plurality of subcarriers, one or more of:

a forward-error-correction (FEC) rate respectively corresponding to the one or more individual subcarriers; and

a symbol rate respectively corresponding to the one or more individual subcarriers,

wherein the symbol rate and the FEC rate are balanced to preserve a data rate for each individual subcarrier of the one or more individual subcarriers.

14 . The operations of claim 13 , further comprising increasing a symbol rate of the one or more individual subcarriers.

15 . The operations of claim 13 , further comprising adjusting a bandwidth of the one or more individual subcarriers without changing an overall bandwidth of the optical signal.

16 . The operations of claim 13 , further comprising adjusting an overall bandwidth of the optical signal by adjusting a bandwidth of the one or more individual subcarriers.

17 . The operations of claim 13 , wherein the optical signal path comprises a metro transmission path in which passband narrowing affects an edge subcarrier of the one or more individual subcarriers or a long-haul path in which cross-modulation affects a center subcarrier of the one or more individual subcarriers.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 29, 2025
From: FUJITSU LIMITED
To: 1FINITY INC.
Reel/Frame 072717/0753 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 6, 2024
From: VASSILIEVA, OLGA I.; KIM, INWOONG; PALACHARLA, PAPARAO
To: FUJITSU LIMITED
Reel/Frame 066397/0351 →
Continuity (1)
Related Publication 20250247157A1 · Jul 31, 2025
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