Direct-detection optical receiver capable of signal-to-signal beat interference cancellation
US11309959B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 2, 2020 |
| Grant date | Apr 19, 2022 |
| Priority date | — |
| Expiry date | Jun 2, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/60
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A direct-detection optical data receiver capable of low-latency SSBI cancellation using one or more FIR filters in the chain of digital signal processing thereof. In an example embodiment, a DSP of the receiver may have first and second serially connected FIR filters whose filter coefficients are updated based on a same feedback signal. An SSBI-cancellation circuit of the DSP is configured to estimate the SSBI by summing a scaled square of the filtered signal generated by the first FIR filter and a scaled square of the filtered signal generated by the second FIR filter. In some embodiments, the SSBI-cancellation circuit may have two or more serially connected stages, each of which incrementally improves the accuracy of the SSBI estimate. In some embodiments, the need for dedicated and/or specialized filter-calibration procedures may beneficially be circumvented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.