{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-8477877","patent":{"patent_number":"US-8477877","title":"Feed-forward carrier phase recovery for optical communications","assignee":null,"inventors":[],"filing_date":"2010-06-23T00:00:00.000Z","publication_date":"2013-07-02T00:00:00.000Z","cpc_codes":["H04B","H04B","H04B","H04L","H04L","H04L","H04Q","H04L","H04L","H04Q"],"num_claims":16,"abstract":"The carrier phase of a carrier wave modulated with information symbols is recovered with a multi-stage, feed-forward carrier phase recovery method. A series of digital signals corresponding to the information signals is received. For each digital signal, a coarse phase recovery is performed to determine a first phase angle which provides a first best estimate of the information symbol corresponding to the digital signal. Using the first best estimate as input, a second stage of estimation is then performed to determine a second phase angle which provides an improved (second) best estimate of the information symbol. Additional stages of estimation can be performed. The multi-stage, feed-forward carrier phase recovery method retains the same linewidth tolerance as a single-stage full blind phase search method; however, the required computational power is substantially reduced. The multi-stage, feed-forward carrier phase recovery method is highly efficient for M-QAM optical signals."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Feed-forward carrier phase recovery for optical communications","description":"The carrier phase of a carrier wave modulated with information symbols is recovered with a multi-stage, feed-forward carrier phase recovery method. A series of digital signals corresponding to the inf","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-8477877","license":"CC-BY-4.0-like","license_terms":"AI-generated analysis on this page (summary, layman_explanation, technical_analysis, business_analysis, faqs) may be reused with attribution and a visible link back to the canonical URL above. Patent abstracts, claims, and bibliographic data are USPTO public domain.","required_link":"https://patentable.app/patents/US-8477877","citation_suggestion":"Patentable. \"Feed-forward carrier phase recovery for optical communications\" (US-8477877). https://patentable.app/patents/US-8477877","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-8477877","json":"https://patentable.app/api/llm-context/US-8477877","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-05-30T14:58:21.798Z"}