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CPC Main Group Additional Only
H04S 2420/00

Techniques used stereophonic systems covered by H04S but not provided for in its groups

6 direct subcodes

Child Classifications

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  • H04S 2420/01 Enhancing the perception of the sound image or of the spatial distribution using head related transfer functions [HRTF's] or equivalents thereof, e.g. interaural time difference [ITD] or interaural level difference [ILD]
  • H04S 2420/03 Application of parametric coding in stereophonic audio systems
  • H04S 2420/05 Application of the precedence or Haas effect, i.e. the effect of first wavefront, in order to improve sound-source localisation
  • H04S 2420/07 Synergistic effects of band splitting and sub-band processing
  • H04S 2420/11 Application of ambisonics in stereophonic audio systems
  • H04S 2420/13 Application of wave-field synthesis in stereophonic audio systems

Top Applicants

Top 10 applicants by patent filingsfor class H04, 2013–2023, worldwide · Source: EPO PATSTAT

  1. HUAWEI TECHNOLOGIES COMPANY CN 101,476
  2. QUALCOMM US 101,139
  3. SAMSUNG ELECTRONICS COMPANY KR 96,655
  4. TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) SE 57,744
  5. LG ELECTRONICS KR 55,253
  6. HUAWEI TECHNOLOGIES COMPANY 54,181
  7. SONY CORPORATION JP 35,309
  8. ZTE CORPORATION CN 32,950
  9. INTEL CORPORATION US 27,533
  10. GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORPORATION CN 27,498