Abstract: A diversity channel for data transmission is obtained by communication equipment. The diversity channel indicates communication resources that are assigned to the communication equipment, and is from a set of diversity channels that are consistent with codewords of a linear code. The communication equipment also transmits a data transmission using the communication resources indicated by the diversity channel. The diversity channel assignment could be determined, by network equipment for example, and information that identifies the diversity channel could be transmitting to the communication equipment. Such information could be explicitly or implicitly signaled to the communication equipment. A set of diversity channels could be generated directly as codewords of one or more linear codes, or additional operations could be applied to such codewords, and possibly other information that is not generated using a code, to provide a diversity channel set.

Abstract: A method and apparatus for (a) operating a first full-duplex transceiver to exchange radio-frequency signals with a second full-duplex transceiver, (b) determining at the first full-duplex transceiver that a residual self-interference signal exceeds a threshold, (c) in response to the determination that the residual self-interference signal exceeds the threshold, performing a self-training operation.

Abstract: Embodiments are directed to a method for encrypting data communications, including performing a stochastic procedure between a plurality of nodes, including at least a first node and a second node; collecting a measured outcome of the stochastic procedure, the measured outcome of the stochastic procedure providing a dependent random variable pair; and constructing an encryption key based on one or more correlations identified between at least a first random variable and a second random variable, the first and second random variables forming the dependent random variable pair.

Abstract: Embodiments include a method for secure data storage including constructing an encryption key from a plurality of key elements, the constructing including distributing the plurality of key elements to a plurality of key maintenance entities, each of the plurality of key maintenance entities employing a plurality of independent safe guards for their respective key elements of the plurality of key elements; and requiring access to the plurality of key elements to construct the encryption key. The method includes receiving a subset of the plurality of key elements via a twice-encrypted communications channel; and regenerating the encryption key at the client node; and after encrypting data, deleting the subset of the plurality of key elements received over the twice-encrypted communications channel, retaining any of the plurality of key elements previously stored at the client node.

Abstract: Embodiments include method for authentication including interacting with a user by a server in real time to collect verification data for authentication by requiring the user to take an action in real time; comparing a detected reaction by the user in response to the requirement to take the action to a predetermined metric; and determining based on the comparison to the predetermined metric, whether to authenticate the user.

Abstract: An apparatus includes a first transceiver, at least two antennas coupled to the first transceiver to exchange one or more keys and phase data with a second transceiver via a plurality of rounds of phase data exchange, each round including: a first pilot signal sent from a first of the antennas of the first transceiver to the second transceiver, a second pilot signal received from the second transceiver, the second pilot signal modulated using a measured first phase of the first pilot signal, a third pilot signal received from the second transceiver; a fourth pilot signal sent from a second of the antennas of the first transceiver to the second transceiver, the fourth pilot signal modulated using a measured second phase of the third pilot signal, and wherein between the plurality of rounds of phase exchange, the first transceiver perturbs a radio frequency (RF) environment surrounding the at least two antennas.

Abstract: A method and apparatus for (a) operating a first full-duplex transceiver to exchange radio-frequency signals with a second full-duplex transceiver, (b) determining at the first full-duplex transceiver that a residual self-interference signal exceeds a threshold, (c) in response to the determination that the residual self-interference signal exceeds the threshold, performing a self-training operation.

Abstract: A full-duplex transceiver is provided with componentry and methods for cancellation of nonlinear self-interference signals. The transceiver is capable of receiving an incoming radio-frequency signal that includes both a desired radio-frequency signal component and a self-interference component caused by the transceiver's own radio-frequency transmission. The transceiver demodulates the incoming radio-frequency signal to generate a first demodulated signal. The transceiver combines an analog corrective signal with the first demodulated signal to generate a second demodulated signal with reduced self-interference. The transceiver processes the first and second demodulated signals to determine a desired incoming baseband signal and to determine nonlinear components of the self-interference signal, such as nonlinearities introduced by the transceiver's power amplifier.

Abstract: The methods and systems for amplify-and-forward (in-band) relaying relate to beamforming techniques including receive and transmit beamforming for reducing self-interference, and improving Signal-to-Noise Ratio (SNR), or Signal to Interference plus Noise Ratio (SINR), of an incoming signal (to be relayed). The incoming signal is amplified and retransmitted simultaneously with the incoming signal, and over the same frequency band as that of an incoming signal.

Abstract: A full-duplex transceiver is provided with componentry and methods for cancellation of nonlinear self-interference signals. The transceiver is capable of receiving an incoming radio-frequency signal that includes both a desired radio-frequency signal component and a self-interference component caused by the transceiver's own radio-frequency transmission. The transceiver demodulates the incoming radio-frequency signal to generate a first demodulated signal. The transceiver combines an analog corrective signal with the first demodulated signal to generate a second demodulated signal with reduced self-interference. The transceiver processes the first and second demodulated signals to determine a desired incoming baseband signal and to determine nonlinear components of the self-interference signal, such as nonlinearities introduced by the transceiver's power amplifier.

Abstract: An antenna assembly includes a first active antenna element and a second active antenna element, each of which may be a dipole. A first set of independently-switchable radio-frequency reflectors are positioned around at least the first active antenna element. These first switchable radio-frequency reflectors may also be positioned around the second active antenna element. Alternatively, a second set of independently-switchable radio-frequency reflectors may be positioned around the second active antenna element. The switchable reflectors enable controlled perturbation of the communication channel between the antenna assembly and a remote communications node, enabling securely encrypted communications.

Abstract: An apparatus includes a first transceiver, at least two antennas coupled to the first transceiver to exchange one or more keys and phase data with a second transceiver via a plurality of rounds of phase data exchange, each round including: a first pilot signal sent from a first of the antennas of the first transceiver to the second transceiver, a second pilot signal received from the second transceiver, the second pilot signal modulated using a measured first phase of the first pilot signal, a third pilot signal received from the second transceiver; a fourth pilot signal sent from a second of the antennas of the first transceiver to the second transceiver, the fourth pilot signal modulated using a measured second phase of the third pilot signal, and wherein between the plurality of rounds of phase exchange, the first transceiver perturbs a radio frequency (RF) environment surrounding the at least two antennas.

Abstract: A method comprising: at a first transceiver, transmitting a plurality of signals to a second transceiver and receiving corresponding receive signals from the second transceiver, wherein each transmitted signal is sent using a channel perturbation; measuring a plurality of phase values, wherein each phase value is a phase difference between one of the plurality of transmitted signals and corresponding receive signal; masking a subsequent phase modulated signal employing phase rotation at the first transceiver using the plurality of phase values.

Abstract: An apparatus is described, along with methods, the apparatus including a half-duplex transceiver including one or more half-duplex antenna terminals, a full-duplex transceiver including one or more full-duplex antennas, and an interface coupled between the half-duplex transceiver and the full duplex transceiver, the interface enabling the one or more half-duplex antenna terminals and the one or more full-duplex antennas to send and receive radio-frequency (RF) signals over a same frequency band simultaneously.

Abstract: Two-way (full-duplex) wireless links in facilitating network management and improve network performance. Once aspect includes methods for network management using a high-throughput channel and a low-throughput channel. Other aspects include methods to facilitate practical realization and improve performance of some of the network information theoretic configurations, such as Space-Division Multiple Access (SDMA) in uplink and downlink, Interference Channel, and other forms of distributed collaborative signaling schemes. Another aspect includes methods to support cognitive wireless networks.

Abstract: Two-way (full-duplex) wireless communications. Various embodiments measure interference channels and provide for interference cancellation in both analog and digital domains to mitigate self-interference. The system supports multiple clients wherein new clients can join the network asynchronously, and also supports Multiple-Input Multiple-Output (MIMO) antennas.

Abstract: An adapter for enabling full-duplex wireless communications is described, along with methods for operating the adapter. The adapter operates as an intermediary between a transmit antenna and receive antenna on the one hand, and a transceiver on the other hand. The adapter communicates with the transceiver using different frequencies for outbound and inbound radio-frequency signals. However, with respect to the transmit antenna and receive antenna, the adapter transmits outbound and receives inbound radio frequency signals using the same frequency. The adapter includes cancellation circuitry to reduce the self-interference cause by transmitting and receiving on the same frequency.

Abstract: A communication system where a central node (base-station or access point) communicates with multiple clients in its neighbourhood using transparent immediate beam-forming. Resource allocation and channel access is such that the central node does not necessarily know when each client starts its transmission. Receive beam-forming in such a system is not possible, as beam-forming coefficients for each client should be selected according to the particular channel realization from that client to the central node. Each client is detected early in its transmission cycle, based on either a signature that is part of the physical characteristics unique to that client, or based on a signature that is intentionally inserted in the clients' signal, and accordingly adjusts its beam-forming coefficients.

Abstract: Methods and apparatuses are described for communicating primary signals over a high-speed primary channel, the primary signals having a beam pattern having a full lobe at a center of an axis of propagation and communicating auxiliary signals over a low-speed auxiliary channel, the auxiliary signals having a decoupled beam pattern having a null at the center of axis of propagation, the high-speed primary channel and low-speed auxiliary channel operating in full duplex.

Abstract: Two-way (full-duplex) wireless links in facilitating network management and improve network performance. Once aspect includes methods for network management using an overlaid network for control signaling. Another aspects include methods to facilitate practical realization and improve performance of some of the network information theoretic configurations, such as Space-Division Multiple Access (SDMA) in uplink and downlink, Interference Channel, and other forms of distributed collaborative signaling schemes. Another aspect includes methods to support cognitive wireless networks.