Abstract: In some example embodiments, there may be provided an apparatus. The apparatus may include a surface including at least one electro-magnetic reflective element programmed to provide a plurality of reflected signals, such that the plurality of reflected signals constructively adds at a location of a receiver of the plurality of reflected signals. Related systems, methods, and articles of manufacture are also described.

Abstract: Techniques for estimating one or more backscatter signals reflected from one or more objects are disclosed. In one example, a backscatter sensor includes, in part, a receiver for receiving a composite signal comprising one or more reflections of a transmitted signal, each reflection being reflected by one of a plurality of objects; and a processor configured to estimate at least a first backscatter component of the composite signal using a progressive interference cancellation technique. The first backscatter component of the composite signal corresponds to a reflection of the transmitted signal from a first object. In one embodiment, the backscatter sensor includes multiple receivers and/or one or more transmitters.

Abstract: A method, a system, and a computer program product for determining a location of a communication device. Data corresponding to a detected transmission of a data packet between a tag device and one or more communication devices is received on one or more communication channels. At least one of a channel state information and a signal strength associated with the detected transmission for each frequency band in a plurality of frequency bands are determined. Based on the determined channel state information, one or more lengths of signal paths corresponding to the detected transmission of the data packet are determined. A shortest length in across one or more communication devices is selected to determine a location of the tag device.

Abstract: A method, a system, and a computer program for executing high resolution spectrum monitoring. A sensor receives an input signal having a varying frequency content over time. One or more samples of the received input signal are sampled. The samples of the received input signal include one or more swept signal samples generated by sweeping, using a center frequency of the sensor, the received input signal across an entire frequency spectrum associated with the received input signal. Sampling of the samples of the received signal is performed while performing the sweeping. The signal samples are processed.

Abstract: A method, a system, and a computer program product for determining a location of a communication device. Data corresponding to a detected transmission of a data packet between a tag device and one or more communication devices is received on one or more communication channels. At least one of a channel state information and a signal strength associated with the detected transmission for each frequency band in a plurality of frequency bands are determined. Based on the determined channel state information, one or more lengths of signal paths corresponding to the detected transmission of the data packet are determined. A shortest length in across one or more communication devices is selected to determine a location of the tag device.

Abstract: A backscatter tag device includes, in part, a receiver configured to receive a packet conforming to a communication protocol defining a multitude of codewords, a codeword translator configured to translate at least a first subset of the multitude of codewords disposed in the packet to a second multitude of codewords defined by the protocol in response to a data the backscatter tag is invoked to transmit, and a transmitter configured to transmit the packet supplied by the codeword translator at a frequency different than the first frequency at which the packer is received. The communication protocol may optionally be the 802.11 g/n, ZigBee or the Bluetooth communication protocol.

Abstract: A backscatter tag communicate device includes, in part, a receiver configured to receive a WiFi packet conforming to a communication protocol defining a multitude of codewords, a mapper configured to map at least a first subset of the multitude of codewords disposed in the packet to a second multitude of codewords defined by the protocol, and a frequency shifter configured to shift a frequency of the second multitude of codewords such that the frequency shifted codewords are characterized by a single sideband spectrum. The communication protocol may be the 802.11b communication protocol. The mapper may optionally map the first subset of the multitude of codewords by changing phases of the first subset of the multitude of codewords.

Abstract: A wireless communication device includes, in part, an analog interference cancellation circuit and a controller. The analog cancellation circuit includes a multitude of delay paths each including a delay element and a variable attenuator. The controller dynamically varies the attenuation level of each of the variable attenuators in accordance with the frequency response characteristic of that attenuator to remove a portion of a self-interference signal present in a signal received by the device. The device measures the frequency response characteristic of the communication channel, used in determining the attenuation levels, via one or more preamble symbols. A second portion of the self-interference signal is removed by the device using a multitude of samples of a transmitted signal and a multitude of samples of a signal to be transmitted.

Abstract: A MIMO wireless communication device includes, in part, a first transmit path adapted to transmit a first transmit signal from a first antenna, a second transmit path adapted to transmit a second transmit signal from a second antenna, a first receive path adapted to receive a first receive signal, an interference cancellation circuit and a controller. The cancellation circuit includes a cascaded filter structure each filter including a multitude of filter taps each including a variable element. The controller dynamically varies a value applied to each of the plurality of variable elements in accordance with frequency response characteristics of the variable element to remove a portion of a self-interference and/or cross-talk interference signal present in a signal received by the device.

Abstract: A system for frequency isolation modified self-interference cancellation includes a transmit coupler, that samples an RF transmit signal; an RF self-interference canceller that transforms the sampled RF transmit signal to an RF self-interference cancellation signal; a receive coupler that combines the RF self-interference cancellation signal with the RF receive signal to form a reduced-interference receive signal; and a frequency shifter that frequency shifts only one of the RF transmit signal and the reduced-interference receive signal.

Abstract: In one aspect there is provided a method. The method may include receiving a first analog radio frequency signal including a signal of interest and an interference signal caused by a second analog radio frequency signal transmitted in full duplex over a channel from which the first analog transmission is received; adjusting at least one of the first analog radio frequency signal and a portion of the second analog radio frequency signal to enable at least one of a reduction or an elimination of the interference signal in an output analog radio frequency signal; combining the first analog radio frequency signal and the portion of the second analog radio frequency signal to generate the output analog radio frequency signal characterized by at least the reduction or the elimination of the interference signal included in the output analog radio frequency signal; and providing the output analog radio frequency signal. Related apparatus, systems, methods, and articles are also described.

Abstract: A system that incorporates the subject disclosure may include, for example, determining an interference based on a channel gain for each signal of a group of signals received at a receiver from a group of transmitters. A determination is made of an interference value based on a group of interference signals received at a receiver from a group of transmitters, wherein the interference value is based on channel gains that are estimated for the group of transmitters, and wherein a portion of the interference is self-interference generated from transmitting and receiving at a same time. One of an analog time domain cancellation, a digital time domain cancellation or both, is performed responsive to a determination that the interference value does not satisfy a threshold range of an analog-to-digital converter of the receiver. Other embodiments are disclosed.

Abstract: A backscatter tag communicate device includes, in part, a receiver configured to receive a WiFi packet conforming to a communication protocol defining a multitude of codewords, a mapper configured to map at least a first subset of the multitude of codewords disposed in the packet to a second multitude of codewords defined by the protocol, and a frequency shifter configured to shift a frequency of the second multitude of codewords such that the frequency shifted codewords are characterized by a single sideband spectrum. The communication protocol may be the 802.11b communication protocol. The mapper may optionally map the first subset of the multitude of codewords by changing phases of the first subset of the multitude of codewords.

Abstract: A system for frequency isolation modified self-interference cancellation includes a transmit coupler, that samples an RF transmit signal; an RF self-interference canceller that transforms the sampled RF transmit signal to an RF self-interference cancellation signal; a receive coupler that combines the RF self-interference cancellation signal with the RF receive signal to form a reduced-interference receive signal; and a frequency shifter that frequency shifts only one of the RF transmit signal and the reduced-interference receive signal.

Abstract: A system for self-interference canceller tuning includes a transmit coupler that creates a sampled analog transmit signal; an analog self-interference canceller that transforms the sampled analog transmit signal to an analog self-interference cancellation signal according to a set of tuning parameters, the set of tuning parameters comprising complex weights for a set of taps of the analog self-interference canceller; a tuning circuit that calculates the set of tuning parameters, and applies the set of tuning parameters to the analog self-interference canceller based on component calibration data of the analog self-interference canceller; and a receive coupler that combines the analog self-interference cancellation signal with the analog receive signal to reduce self-interference in the analog receive signal.

Abstract: A system for frequency-isolated self-interference cancellation includes a transmit coupler, that samples an RF transmit signal to create a sampled RF transmit signal having a first RF carrier frequency, an RF self-interference canceller that transforms the sampled RF transmit signal to an RF self-interference cancellation signal, a receive coupler, that combines the RF self-interference cancellation signal with an RF receive signal to form a reduced-interference receive signal, and a frequency shifter.

Abstract: A system for self-interference canceller tuning includes a transmit coupler that creates a sampled analog transmit signal; an analog self-interference canceller that transforms the sampled analog transmit signal to an analog self-interference cancellation signal according to a set of tuning parameters, the set of tuning parameters comprising complex weights for a set of taps of the analog self-interference canceller; a tuning circuit that calculates the set of tuning parameters, and applies the set of tuning parameters to the analog self-interference canceller based on component calibration data of the analog self-interference canceller; and a receive coupler that combines the analog self-interference cancellation signal with the analog receive signal to reduce self-interference in the analog receive signal.

Abstract: A system that incorporates the subject disclosure may include, for example, determining an interference based on a channel gain for each signal of a group of signals received at a receiver from a group of transmitters. A determination is made of an interference value based on a group of interference signals received at a receiver from a group of transmitters, wherein the interference value is based on channel gains that are estimated for the group of transmitters, and wherein a portion of the interference is self-interference generated from transmitting and receiving at a same time. One of an analog time domain cancellation, a digital time domain cancellation or both, is performed responsive to a determination that the interference value does not satisfy a threshold range of an analog-to-digital converter of the receiver. Other embodiments are disclosed.

Abstract: A method for self-interference canceller tuning for a near band radio includes receiving, in a first frequency band, an RF transmit signal of the near band radio; receiving, in a second frequency band, an RF receive signal of the near band radio; generating a self-interference cancellation signal from the RF transmit signal based on a set of configuration parameters; combining the self-interference cancellation signal with the RF receive signal to create a composite receive signal; and adapting the set of configuration parameters based on the compo-site receive signal.

Abstract: A method for tuning an analog self-interference canceller includes detecting a tuning trigger, calculating a set of tuning parameters (the tuning parameters including complex weights for a set of taps of the analog self-interference canceller) in response to the tuning trigger, and applying the set of tuning parameters based on component calibration data.