H04J
Multiplex communication
Official title: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S)
H04J (Multiplex communication) appears on 37,042 US grants and 33,492 published applications in this corpus.
Search patents in H04J- Granted patents
- 37,042
- Published applications
- 33,492
- Assignees
- 4,984
- Inventors
- 42,574
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 86 | 0 |
| 1977 | 83 | 0 |
| 1978 | 81 | 0 |
| 1979 | 61 | 0 |
| 1980 | 73 | 0 |
| 1981 | 68 | 0 |
| 1982 | 92 | 0 |
| 1983 | 73 | 0 |
| 1984 | 72 | 0 |
| 1985 | 82 | 0 |
| 1986 | 82 | 0 |
| 1987 | 107 | 0 |
| 1988 | 141 | 0 |
| 1989 | 172 | 0 |
| 1990 | 163 | 0 |
| 1991 | 184 | 0 |
| 1992 | 208 | 0 |
| 1993 | 219 | 0 |
| 1994 | 342 | 0 |
| 1995 | 336 | 0 |
| 1996 | 451 | 0 |
| 1997 | 417 | 0 |
| 1998 | 641 | 0 |
| 1999 | 613 | 0 |
| 2000 | 584 | 0 |
| 2001 | 708 | 319 |
| 2002 | 697 | 1225 |
| 2003 | 839 | 1147 |
| 2004 | 791 | 1177 |
| 2005 | 747 | 1016 |
| 2006 | 1073 | 986 |
| 2007 | 871 | 1120 |
| 2008 | 907 | 1035 |
| 2009 | 918 | 1210 |
| 2010 | 1048 | 1363 |
| 2011 | 1020 | 1184 |
| 2012 | 1210 | 1287 |
| 2013 | 1389 | 1536 |
| 2014 | 1614 | 1674 |
| 2015 | 1808 | 1940 |
| 2016 | 1862 | 1851 |
| 2017 | 1919 | 1648 |
| 2018 | 1660 | 1775 |
| 2019 | 1898 | 1689 |
| 2020 | 1808 | 1717 |
| 2021 | 1507 | 1406 |
| 2022 | 1386 | 1270 |
| 2023 | 1249 | 1314 |
| 2024 | 1174 | 1086 |
| 2025 | 926 | 926 |
| 2026 | 582 | 591 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Main groups
Granted patents with any code in the group
- H04J 3/00Time-division multiplex systems14,734
- H04J 14/00Optical multiplex systems10,432
- H04J 11/00Orthogonal multiplex systems6,786
- H04J 13/00Code division multiplex systems5,346
- H04J 2203/00Aspects of optical multiplex systems other than those covered by h04j14/05 andIndexing code2,423
- H04J 1/00Frequency-division multiplex systems903
- H04J 4/00Combined time-division and frequency-division multiplex systems289
- H04J 2211/00Orthogonal indexing scheme relating to orthogonal multiplex systemsIndexing code256
Recent patents
- Methods and systems for decentralized rail signaling and positive train control6 Oct 2026US 12,752,823 B2Metrom Rail, LLC
- Technologies for optical demultiplexing with backwards compatibility6 Oct 2026US 12,754,364 B2Intel Corporation
- Optical time domain reflectometer (OTDR)-based fiber monitoring optimization6 Oct 2026US 12,756,459 B2Viavi Solutions Inc.
- Optical transmitter including splitting elements, external modulators, and wavelength multiplexers, and optical transceiver including polarization separation elements, wavelength demultiplexers, polarization rotation elements, and photodetectors6 Oct 2026US 12,756,476 B2Mitsubishi Electric Corporation
- Systems and methods for synchronizing device clocks6 Oct 2026US 12,756,491 B2Bose Corporation
- Bistatic radar sensing in the presence of synchronization signals8 Oct 2026US 2026/0309854 A1Telefonaktiebolaget LM Ericsson (publ)
- Communication method and apparatus8 Oct 2026US 2026/0312710 A1Huawei Technologies Co., Ltd.
- Time synchronization techniques8 Oct 2026US 2026/0312711 A1Dell Products L. P.
- Otn device, service management system, and automatic connection method of otn sub-device8 Oct 2026US 2026/0312712 A1Zte Corporation
- Clock forwarding in packaged optics links8 Oct 2026US 2026/0312713 A1Lightmatter, Inc.
Most cited
By later US patents
- System and method for synchronizing operations among a plurality of independently clocked digital data processing devices1,949US 8,234,395 B2Sonos, Inc. · 2012
- Multimedia wired/wireless content synchronization system and method1,810US 6,631,410 B1Sharp Laboratories of America, Inc. · 2003
- System for synchronizing a plurality of nodes to concurrently generate output signals by adjusting relative timelags based on a maximum estimated timelag1,773US 5,923,902 AYamaha Corporation · 1999
- System and method for generating signal waveforms in a CDMA cellular telephone system1,721US 5,103,459 AQUALCOMM Incorporated · 1992
- Method and apparatus for demodulating signals in a pulse oximetry system1,090US 6,229,856 B1Masimo Corporation · 2001