In a system for physical-layer security, a sender may encode a message word using a secrecy-code encoding, an error-propagation encoding, and an error-correction encoding, and transmit the encoded message word on a data transmission medium. An intended recipient may receive a word having errors from the noise on the intended recipient's channel, and may decode the received word using an error-correction decoder, an error-propagation decoder, and a secrecy-code decoder. If an eavesdropper's channel is noisier than the intended recipient's channel, the system may be tuned to correct all errors on the intended recipient's channel, but leave, on the eavesdropper's channel, errors that will be propagated and amplified into noise. In an alternate embodiment, a sender and an intended recipient may share a secret key and may use the shared secret key, or values generated by the shared secret key, to populate frozen bits in a polar coding scheme.channel.

In a system for physical-layer security, a sender may encode a message word using a secrecy-code encoding, an error-propagation encoding, and an error-correction encoding, and transmit the encoded message word on a data transmission medium. An intended recipient may receive a word having errors from the noise on the intended recipient's channel, and may decode the received word using an error-correction decoder, an error-propagation decoder, and a secrecy-code decoder. If an eavesdropper's channel is noisier than the intended recipient's channel, the system may be tuned to correct all errors on the intended recipient's channel, but leave, on the eavesdropper's channel, errors that will be propagated and amplified into noise. In an alternate embodiment, a sender and an intended recipient may share a secret key and may use the shared secret key, or values generated by the shared secret key, to populate frozen bits in a polar coding scheme.channel.

In some examples, methods and systems may process one or more payment transactions between a merchant and a buyer by registering a communication device as an authorization instrument to the payment transaction. To this end, the method includes detecting at least one transaction activity associated with a payment system, establishing a communication channel between the POS terminal an RF communication device in proximity to the POS terminal. Then obtaining at least one device characteristic of the communication device, wherein the device characteristic is related to the operational or physical features of the communication device; generating a digital fingerprint based in part on the obtained device characteristic and the information related to received payment object; determining whether the digital fingerprint substantially compares to an existing fingerprint in a database and if the existing fingerprint is substantially similar to the digital fingerprint, authorizing the payment transaction through presence of the communication device.

A system and method are provided for generating a Short Term Key Message (STKM) for protection of a broadcast service being broadcasted to a terminal in a mobile broadcast system. The method includes transmitting, by a Broadcast Service Subscription Management (BSM) for managing subscription information, at least one key information for authentication of the broadcast service to a Broadcast Service Distribution/Adaptation (BSD/A) for transmitting the broadcast service, generating, by the BSD/A, a Traffic Encryption Key (TEK) for deciphering of the broadcast service in the terminal and inserting the TEK into a partially created STKM, and performing, by the BSD/A, Message Authentication Code (MAC) processing on the TEK-inserted STKM using the at least one key information, thereby generating a completed STKM.

Methods and apparatus for distribution of keys are disclosed. An optical signal for carrying encoded information in accordance with a quantum key distribution scheme is generated. The generated optical signal has a wavelength which is changed to another wavelength prior to transmission of the optical signal. The optical signal carrying the encoded information and having the changed wavelength is received, where after decoding of the information takes place by means of detector apparatus operating in the changed wavelength.

A multi-protocol RFID interrogating system employs a synchronization technique (step-lock) for a backscatter RFID system that allows simultaneous operation of closely spaced interrogators. The multi-protocol RFID interrogating system can communicate with backscatter transponders having different output protocols and with active transponders including: Title 21 compliant RFID backscatter transponders; IT2000 RFID backscatter transponders that provide an extended mode capability beyond Title 21; EGO™ RFID backscatter transponders, SEGO™ RFID backscatter transponders; ATA, ISO, ANSI AAR compliant RFID backscatter transponders; and IAG compliant active technology transponders. The system implements a step-lock operation, whereby adjacent interrogators are synchronized to ensure that all downlinks operate within the same time frame and all uplinks operate within the same time frame, to eliminate downlink on uplink interference.

Controlling access to position information at a receiver, or at another device external to the receiver. Various considerations, including a requested service type, a user type, a device type, a software application type, a payment, and/or other characteristics associated with a particular software application or distributor of that software application, may be used to control access to position information.

An optical security method for object authentication using photon-counting encryption implemented with phase encoded QR codes. By combining the full phase double-random-phase encryption with photon-counting imaging method and applying an iterative Huffman coding technique, encryption and compression of an image containing primary information about the object is achieved. This data can then be stored inside of an optically phase-encoded QR code for robust read out, decryption, and authentication. The optically encoded QR code is verified by examining the speckle signature of the optical masks using statistical analysis.

The positioning signals broadcast by the GNSS constellations on civilian frequencies are likely to be counterfeited, while the use of authentic signals is becoming increasingly critical for certain applications. According to the invention, the authentication of GNSS signals is performed by analysis of consistency between the measurements of parameters characteristic of the signals (direction of arrival, amplitude, phase) and their state model, said state model taking account of an emulation by software and electronic means of displacements of the phase centre of the antenna and/or of the main lobe of the radiation pattern. Advantageously, these displacements are generated by a pseudo-random code. Advantageously, the analysis of consistency between measurements and models is a multiple-criterion analysis, the combination of criteria being chosen as a function of a reception quality indicator and/or of a presumed location.

A device for sound wave communication, including: a hardware correction table for setting a correction frequency band; a sound wave transmission unit for generating data frequencies at a predetermined base decibel level, generating separate reception filter frequencies at the base decibel level for receiving data carried by a sound wave transmitted from the nearest location when sound waves are received, and generating the correction reference frequency at the base decibel level for correcting hardware transmission; and a sound wave reception unit for receiving a sound wave signal transmitted from the sound wave transmission unit, extracting decibel levels at each of the data frequencies to form an array of decibel levels, correcting the array by shifting the array by a correction value extracted using the hardware correction table, and reconstructing data.