H04K 1/02
Secret communication: by adding a second signal to make the desired signal
Official title: by adding a second signal to make the desired signal unintelligible
H04K1/02 (Secret communication: by adding a second signal to make the desired signal) appears on 305 US grants and 232 published applications in this corpus.
Search patents in H04K- Granted patents
- 305
- Published applications
- 232
- Assignees
- 198
- Inventors
- 627
- Latest grant
- 24 Mar 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 12 | 0 |
| 1977 | 4 | 0 |
| 1978 | 2 | 0 |
| 1979 | 6 | 0 |
| 1980 | 3 | 0 |
| 1981 | 3 | 0 |
| 1982 | 2 | 0 |
| 1983 | 4 | 0 |
| 1984 | 2 | 0 |
| 1985 | 2 | 0 |
| 1986 | 6 | 0 |
| 1987 | 4 | 0 |
| 1988 | 4 | 0 |
| 1989 | 2 | 0 |
| 1990 | 3 | 0 |
| 1991 | 5 | 0 |
| 1992 | 7 | 0 |
| 1993 | 6 | 0 |
| 1994 | 9 | 0 |
| 1995 | 2 | 0 |
| 1996 | 2 | 0 |
| 1997 | 4 | 0 |
| 1998 | 2 | 0 |
| 1999 | 2 | 0 |
| 2000 | 3 | 0 |
| 2001 | 3 | 1 |
| 2002 | 5 | 9 |
| 2003 | 3 | 11 |
| 2004 | 3 | 7 |
| 2005 | 4 | 5 |
| 2006 | 5 | 13 |
| 2007 | 3 | 9 |
| 2008 | 8 | 16 |
| 2009 | 6 | 8 |
| 2010 | 11 | 13 |
| 2011 | 12 | 11 |
| 2012 | 12 | 4 |
| 2013 | 13 | 9 |
| 2014 | 10 | 5 |
| 2015 | 12 | 11 |
| 2016 | 5 | 10 |
| 2017 | 10 | 11 |
| 2018 | 6 | 3 |
| 2019 | 10 | 7 |
| 2020 | 8 | 19 |
| 2021 | 10 | 9 |
| 2022 | 11 | 12 |
| 2023 | 13 | 9 |
| 2024 | 10 | 8 |
| 2025 | 9 | 10 |
| 2026 | 2 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Injectable hardware and software attestation of sensory input data24 Mar 2026US 12,585,828 B2Red Balloon Security, Inc.
- Lane scrambling over network communication channels3 Mar 2026US 12,567,921 B1Mellanox Technologies, Ltd.
- Joint random subcarrier selection and channel-based artificial signal design aided pls9 Dec 2025US 12,494,862 B2
- Systems and methods for subscription and identity authentication management19 Aug 2025US 12,395,480 B2Nic.Kl Inc.
- Secure short-range communications link for medical devices29 Jul 2025US 12,375,925 B2Impulse Dynamics NV
- Covert transmission method against active and passive cooperative attacks in cognitive radio network20 Aug 2026US 2026/0246557 A1China Three Gorges University
- Lane scrambling over network communication channels5 Mar 2026US 2026/0067020 A1Mellanox Technologies, Ltd.
- Secure short-range communications link for medical devices20 Nov 2025US 2025/0358619 A1Impulse Dynamics NV
- Multi-transmission artificial noise (an) cancellation11 Sep 2025US 2025/0286645 A1QUALCOMM Incorporated
- Communication method, first device, and second device11 Sep 2025US 2025/0286755 A1Guangdong Oppo Mobile Telecommunications Corp., Ltd.
Most cited
By later US patents
- Disruption of speech understanding by adding a privacy sound thereto233US 7,363,227 B2Herman Miller, Inc. · 2008
- Secure open-air communication system utilizing multi-channel decoyed transmission229US 7,848,517 B2AT&T Intellectual Property II, L. P. · 2010
- Authentication system for digital cellular communications227US 5,091,942 AEricsson GE Mobile Communications Holding, Inc. · 1992
- Apparatus and methods for including codes in audio signals202US 6,421,445 B1Arbitron Inc. · 2002
- Digital data cryptographic system187US 5,406,627 ANEC Home Electronics Ltd. · 1995