{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-9769004","patent":{"patent_number":"US-9769004","title":"Data transmission via multi-path channels using orthogonal multi-frequency signals with differential phase shift keying modulation","assignee":null,"inventors":[],"filing_date":"2015-11-23T00:00:00.000Z","publication_date":"2017-09-19T00:00:00.000Z","cpc_codes":["H04L","H04B","H04L","H04L","H04L","H04L","H04L","H04L"],"num_claims":18,"abstract":"A method and an apparatus relating to an OFDM data communications system where the sub-carriers are modulated using differential quadrature phase-shift keying (DQPSK). The multi-carrier transmitted signal is directly generated by means of summation of pre-computed sample points. As part of the multi-carrier signal generation, a signal for the guard interval is established. In an acoustic application of this approach, direct radiation of the sub-carrier approach is facilitated. Symbol synchronization in the receiver is based on signal correlation with the missed sub-carrier. Separation of the sub-carriers in the receiver by means of correlation of the received signal and reference signals that are derived from a table of pre-computed values. Optimal non-coherent processing of the sub-carriers without any phase tracking procedures is achieved."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Data transmission via multi-path channels using orthogonal multi-frequency signals with differential phase shift keying modulation","description":"A method and an apparatus relating to an OFDM data communications system where the sub-carriers are modulated using differential quadrature phase-shift keying (DQPSK). The multi-carrier transmitted si","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-9769004","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-9769004","citation_suggestion":"Patentable. \"Data transmission via multi-path channels using orthogonal multi-frequency signals with differential phase shift keying modulation\" (US-9769004). https://patentable.app/patents/US-9769004","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-9769004","json":"https://patentable.app/api/llm-context/US-9769004","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-06-06T08:21:29.463Z"}