Systems and methods for extracting polarized sub-signals from a dual-polarized signal includes isolating the polarized sub-signals using one or more filters. When a single filter is used to derive a first sub-signal, analog interference cancellation may be used to derive the second sub-signal. When two filters are used, the first and second sub-signals may each be derived using a corresponding filter.

Portable communication device and method for mitigating interference. One example portable communication device includes a frequency-modulated (FM) communication subsystem, a cellular communication subsystem, a first electronic processor, and a second electronic processor. The FM communication subsystem includes an FM modem and at least one FM antenna. The cellular communication subsystem includes a plurality of cellular antennas, a plurality of antenna tuners, and a cellular modem. The first electronic processor is configured to generate an alert signal responsive to detecting one of an audio signal reception by the FM communication subsystem and an audio signal transmission by the FM communication subsystem. The second electronic processor is configured to receive the alert signal from the first electronic processor. The second electronic processor is also configured to responsively cause the cellular communication subsystem to set substantially constant impedances for the plurality of cellular antennas.

A method and system for selecting a sub-band in a television white space frequency band may include configuring an antenna matching circuit based on the selected sub-band and configuring a bandpass filter based on the selected sub-band. The method may include receiving a first signal through a radio-frequency path including the antenna matching circuit and not including the bandpass filter, measuring a parameter of received first signal, and determining whether the selected sub-band is usable based on the measured parameter of the received first signal. The method may include receiving a second signal through radio-frequency path including the antenna matching circuit and the bandpass filter, measuring a parameter of the received second signal, and determining whether the selected sub-band is usable based on the measured parameter of the received second signal.

A signaling circuit having a selectable-tap equalizer. The signaling circuit includes a buffer, a select circuit and an equalizing circuit. The buffer is used to store a plurality of data values that correspond to data signals transmitted on a signaling path during a first time interval. The select circuit is coupled to the buffer to select a subset of data values from the plurality of data values according to a select value. The equalizing circuit is coupled to receive the subset of data values from the select circuit and is adapted to adjust, according to the subset of data values, a signal level that corresponds to a data signal transmitted on the signaling path during a second time interval.

Examples of backscatter systems, device, and techniques are described herein. Example backscatter devices may utilize CSS modulation to provide backscatter signals including CSS signals (e.g., LoRa packets). Utilizing CSS modulation may advantageously allow for backscatter communication over wide areas. Examples of backscatter devices described herein may toggle the impedance of the backscatter device between multiple (e.g., eight) impedances to reduce and/or eliminate higher order harmonic components in the backscatter signal (e.g., third and fifth harmonic components).

An antenna device includes an antenna unit and reflecting units. The antenna unit is arranged on a substrate. The reflecting units are arranged separately from each other on the substrate and surrounding the antenna unit. The reflecting units are configured to adjust a radiation pattern of the antenna unit, and each of the reflecting units includes a first portion and a second portion. The first portion has an upper side and a lower side, and the lower side of the first portion is coupled to the substrate. The second portion has a lower side connected to the upper side of the first portion. A width of the lower side of the first portion is smaller than a width of the lower side of the second portion.

A waveform shaping device that includes an adaptable surface, a controller, and a receiving device which measures a secondary wave following the reception of a primary wave by a receiver, the primary wave having been transmitted by a transmitter. Based on the measurement of the secondary wave, the controller determines an estimated value for optimization of the adaptable surface, without any connection to the receiver.

A discrete-time delay (TD) technique in a baseband receiver array is disclosed for canceling wide modulated bandwidth spatial interference and reducing the Analog-to-Digital Conversion (ADC) dynamic range requirements. In particular, the discrete-time delay (TD) technique first aligns the interference using non-uniform sampled phases followed by uniform cancellation using a cancellation matrix, such as, for example, a Truncated Hadamard Transform implemented with antipodal binary coefficients.

The present invention teaches the implementation for a system of networked heterogenous signal capture and analysis sensor-enabled devices tethered in a cooperative multi-protocol wireless local area network (WLAN) providing an automated safety monitoring and response services during an active shooter situation. The present invention describes a method to leverage the standard sensors on most smartphones into a real-time swarming of localized tracking, monitoring and guidance networked to direct people to identified safe zones in the covered build and public venues. The system utilizes multi-device real-time two-way positioning/ranging with acoustic based source geo-location algorithm to pinpoint danger regions within the coverage area. The response system described in this invention activates automatically upon detection of discharge of any firearm in the protected area without manual intervention.

A signaling circuit having a selectable-tap equalizer. The signaling circuit includes a buffer, a select circuit and an equalizing circuit. The buffer is used to store a plurality of data values that correspond to data signals transmitted on a signaling path during a first time interval. The select circuit is coupled to the buffer to select a subset of data values from the plurality of data values according to a select value. The equalizing circuit is coupled to receive the subset of data values from the select circuit and is adapted to adjust, according to the subset of data values, a signal level that corresponds to a data signal transmitted on the signaling path during a second time interval.