{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-9847818","patent":{"patent_number":"US-9847818","title":"Channel state information (CSI) feedback and subsampling","assignee":null,"inventors":[],"filing_date":"2014-06-04T00:00:00.000Z","publication_date":"2017-12-19T00:00:00.000Z","cpc_codes":["H04B","H04B","H04B","H04B","H04B","H04B","H04B","H04B","H04B","H04B","H04L","H04L"],"num_claims":8,"abstract":"A method implemented in a base station used in a wireless communications system is disclosed. The method comprises receiving, from a user equipment, rank indication (RI), a first precoding matrix indicator (PMI), and a second PMI (codebook index i2), wherein values 0-15 are assigned to the second PMI IPMI2 for RI=1 and values 0-3 are assigned to the second PMI IPMI2 for each of RI=2, RI=3, and RI=4, and wherein codebook index i2 comprises IPMI2 for RI=1. Other methods, apparatuses, and systems also are disclosed."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Channel state information (CSI) feedback and subsampling","description":"A method implemented in a base station used in a wireless communications system is disclosed. The method comprises receiving, from a user equipment, rank indication (RI), a first precoding matrix indi","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-9847818","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-9847818","citation_suggestion":"Patentable. \"Channel state information (CSI) feedback and subsampling\" (US-9847818). https://patentable.app/patents/US-9847818","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-9847818","json":"https://patentable.app/api/llm-context/US-9847818","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-06-06T10:17:11.502Z"}