CPC Definition - Subclass H04K
This place covers:
This subclass covers secret line and radiation transmission systems in which the signal is modified at the transmitting station in such a way that the information cannot be intelligibly received without corresponding modification at the receiving station.
The signal can be modified using, for example, frequency scrambling or scrambling by combination with a second signal.
This subclass also covers the jamming of communications and counter-measures against jamming or against surveillance.
Systems using reduced bandwidth or suppressed carrier techniques, or using sub-carriers or spread spectrum techniques are classified in H04B. In particular, spread spectrum as counter-measure against jamming is classified in H04K 3/00 whereas spread spectrum communication as such is classified in H04B.
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Means for anti-jamming used in radar or analogous systems | |
Jamming means used in radar or analogous systems | |
Counter-measures or counter-counter-measures used in lidar or analogous systems | |
Counter-measures or counter-counter-measures used in sonar or analogous systems | |
Arrangements for the secret or secure communication of digital information, encryption of digital signals | |
Secrecy systems used in scanning, transmission or reproduction of documents | |
Analogue secrecy systems or analogue subscription systems for television |
Attention is drawn to the following places, which may be of interest for search:
Arrangements for protecting computers or computers systems | |
Ciphering or deciphering apparatus per se | |
Systems with reduced bandwidth or suppressed carrier | |
Spread spectrum techniques | |
Photonic quantum communication | |
Protection from unauthorised access for optical transmission, e.g. eavesdrop protection | |
Transmission systems characterised by the use of a sub-carrier | |
Arrangements for preventing the taking of data from a data transmission channel without authorisation | |
Selective content distribution, e.g. interactive television, VOD |
In this place, the following terms or expressions are used with the meaning indicated:
Secret communication | Secret line and radiation transmission systems, i.e., those in which the signal is modified at the transmitting station in such a way that the information cannot be intelligibly received without corresponding modification at the receiving station. |
Jamming of communication | Apparatus, circuits or systems purposefully trying to interfere with the physical transmission and reception of communication. |
Frequency scrambling | Transposing or inverting parts of the frequency band or by inverting the whole band |
Follower jammer | Jammer adapted to determine and follow the frequency of a jamming target signal that uses frequency hopping techniques |
Look-through mode | Operation mode wherein jamming and monitoring of the jamming target alternate |
Reactive jammer | Jammer wherein jamming is activated only when a target has been detected |
RCIED | Remote Controlled Improvised Explosive Device |
In patent documents, the following words/expressions are often used as synonyms:
- "confidential", "sensitive", "undercover", "private", "sneaky"
- "hidden", "scrambled", "blinded", "obscured", "obfuscated", "masked", "concealed", "covert", "coded"
This place covers:
Secret communication in the analogue domain for speech and non-speech data.
Secret communication in the analogue domain, or analogue scrambling, jamming or counter-measures are classifed in H01K 1/00 whereas transmission systems for the secret or secure communication of digital information are classified in H04L, with details of encryption in the digital domain most likely classified in H04L 9/00 and H04L 12/00.
Attention is drawn to the following places, which may be of interest for search:
Ciphering or deciphering apparatus per se | |
Systems with reduced bandwidth or suppressed carrier | |
Spread spectrum techniques in general | |
By using a sub-carrier | |
By multiplexing | |
Transmission systems for secret digital information, encryption of digital signals | |
Secret or subscription television systems |
This place covers:
"jamming", only when it means purposefully trying to interfere with the physical transmission and reception of communication.
Provided this condition is met, this group covers devices and methods for:
- countermeasures against jamming (H04K 3/20);
- countermeasures against undesired self-jamming resulting from jamming (H04K 3/28);
- countermeasures against surveillance, interception or detection (H04K 3/82);
- other electronic countermeasures using or against electromagnetic or acoustic waves (H04K 3/00);
- signal detection techniques used in relation to jamming for interception and monitoring of the jamming target signal (H04K 3/45);
- signal detection techniques used in relation to anti-jamming for jamming detection (H04K 3/22);
- signal detection techniques used in relation to anti-surveillance for surveillance detection (H04K 3/822)
In particular, this group covers:
- jamming for testing or assessing countermeasures (H04K 3/94);
- jamming used to prevent cellular phone communication (H04K 2203/16), e.g. in a vehicle during motion (H04K 3/415), in particular areas, including prisons, hospitals, planes, petrol stations, theatres (H04K 3/84), and to trigger RCIEDs (H04K 3/92 and H04K 2203/24);
- jamming used to prevent reception of positioning data using GPS (H04K 3/90);
- jamming used to prevent wireless communication in ad hoc networks or in sensor networks (H04K 2203/18);
- jamming used to prevent exchange of data between wirelessly connected devices or device units, on Bluetooth, infrared or near field links;
- jamming used to prevent unauthorized access to network, service or information (H04K 3/86), including access to a WLAN network (H04K 2203/18) and access to information stored in contactless carriers, including RFID carriers (H04K 2203/20);
- jamming used to prevent transmission of an alarm against burglary or vehicle theft (H04K 3/88);
- jamming used to prevent remote control of devices (H04K 3/92);
- jamming used to prevent surveillance (H04K 3/82), e.g. of speech in meeting rooms (H04K 2203/12), of electromagnetic emissions from a computer screen H04K 2203/14);
- jamming used to prevent interception or detection of a wirelessly transmitted signal (H04K 3/825).
Terminology
Jamming should be understood as meaning "intentional disturbance".
Interference should be understood as meaning "unintentional disturbance".
Anti-jamming
Jamming and anti-jamming techniques are covered by H04K 3/00 and lower.
Anti-interference techniques are covered by H04B.
Cancellation of "self-jamming"
- intentional self-jamming (e.g. self-jamming of receiver to counter interference; self-jamming of transmitter to counter surveillance): H04K;
- undesired self-jamming caused by transmitting: H04B 1/525;
- undesired self-jamming caused by transmitting a jamming signal intentionally: H04B 1/525 and H04K 3/28;
If the intentional self-jamming signal is known by the transmitter and the receiver of the jammed signal (and can therefore be regarded as a shared secret): H04K 1/00
Other cases of intentional self-jamming: H04K 3/00
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Counter-measures used in radar or analogous systems | |
Counter-measures used in radar | |
Counter-measures used in lidar | |
Counter-measures used in sonar |
Attention is drawn to the following places, which may be of interest for search:
Secret communication | |
Vehicle anti-theft relating to remote keyless entry | |
Vehicle anti-theft alarm transmission | |
Weapons | |
Defence devices | |
Radars and GPS | |
Counter-measures used in radar or analogous systems | |
Remote keyless entry | |
Alarm and surveillance | |
Acoustics | |
Aerials | |
Gain control | |
Automatic frequency control | |
Electric pulse generators | |
Transmission | |
Reducing, in transceivers, leakage of transmitter signal into the receiver | |
Spread spectrum techniques | |
Suppression or limitation of noise or interference | |
Monitoring or testing of receivers for locating or positioning the transmitter | |
Measuring or estimating channel quality parameters | |
Flow control or congestion control packet switching networks | |
Network architectures or network communication protocols for network security for supporting lawful interception, monitoring or retaining of communications or communication related information | |
Handfree telephone for vehicles | |
Television systems | |
Wireless communications networks | |
Wireless security | |
Cognitive radio | |
Wireless local area networks (WLAN) | |
Self-organizing networks, ad-hoc networks and sensor networks | |
Shielding |
A patent document should be classified in H04K 3/20 when the countered signal disturbance is:
- intentional (whether offensive or defensive) or
- used in a military, security or confidentiality context.
In this place, the following terms or expressions are used with the meaning indicated:
Jamming of communication | Purposefully trying to interfere with the physical transmission or reception of communication |
Self-jamming resulting from jamming | Undesired interference, caused by a jamming device, to the communication of the jamming device itself or of a friendly device, and resulting from intentionally interfering with the communication of adversary devices |
Follower jammer | Jammer adapted to determine and follow the frequency of a jamming target signal that uses frequency hopping techniques |
Look-through mode | Operation mode wherein jamming and monitoring of the jamming target alternate |
Reactive jammer | Jammer wherein jamming is activated only when a target has been detected |
In patent documents, the following abbreviations are often used:
(F)FH | (Fast) Frequency Hopping |
GPS | Global Positioning System |
NFC | Near Field Communication |
RCIED | Remote Controlled Improvised Explosive Device |
RFID | Radio Frequency IDentification |
WLAN | Wireless Local Area Network |
Attention is drawn to the following places, which may be of interest for search:
Arrangements for sensing record carriers including arrangements for protecting the interrogation against piracy attacks | |
Means for preventing undesired reading or writing from or onto record carriers by hindering electromagnetic reading or writing |