A wireless sound-emitting device includes a housing adapted to be coupled to a wall at a source of electric power, a loudspeaker positioned at a periphery of the housing, a control module outputting an electric audio signal to the at least one loudspeaker, and a wireless communications module in electrical communication with the control module. The loudspeaker emits acoustic signals in a direction parallel to the wall, when the housing is coupled to the wall, with the acoustic signals reflecting off the wall. The device may produce a sound masking noise or play a sound recorded on an internal memory. The device may include an electric plug or be adapted to replace an electric outlet faceplate. The device may have electric pass-through outlets and may be powered by the source of electric power. The device may be controlled remotely, for example via an Internet of Things (IoT) platform.

A portable Electromagnetic Countermeasure (ECM) device is disclosed for military and civilian population protection from electromagnetic communications and attack, including cell phones, radios, radio-triggered explosive devices, and other personal and portable devices comprising transmitters and receivers. The portable ECM device is usable by a person such as a soldier or policeman to protect themselves and other people around them from spy, guerrilla, military and terrorist threats. The portable (ECM) device comprises a first antenna and a second antenna, both to communicate radio signals with a software defined radio (SDR), and a control pack having a microprocessor operable by remote network connection, or by a mode selector on board the device, to control the SDR according to a mode selected, to receive, produce, and classify radio signals.

Disclosed is a radio frequency communication and jamming device configured for physically secured friendly radio frequency communication and for jamming hostile radio frequency communication, the radio frequency communication and jamming device including: an antenna arrangement having a transmission section for transmitting outgoing signals and a receiving section for receiving incoming signals; a receiver device configured for extracting an incoming information signal from the incoming signals received via the receiving section of the antenna arrangement in a receiving frequency band; a jamming generator configured for generating at least one jamming signal for jamming at least one jamming frequency band, wherein the jamming signal is transmitted as one of the outgoing signals via the transmission section, wherein the at least one jamming frequency band includes the receiving frequency band; and a self-interference cancellation device configured for cancelling portions of the at least one jamming signal in the incoming signals received via the receiving section at least in the receiving frequency band.

A speech reproduction device for reproducing speech based on a received speech signal so that the reproduced speech is intelligible in a clear speech zone and unintelligible in a masked speech zone includes an audio processing module configured for receiving the speech signal; a set of speech loudspeakers configured for reproducing the speech based on one or more speech loudspeaker signals; and a set of masking sound loudspeakers configured for producing a masking sound based on one or more masking sound loudspeaker signals, wherein the masking sound masks the speech in the masked speech zone; wherein the audio processing module includes a speech signal analysis module configured for producing one or more analysis signals based on spectral and/or temporal characteristics of the speech signal; wherein the audio processing module includes a masking sound generator configured for producing one or more masking sound signals based on the one or more analysis signals.

A method improves an anti-eavesdropping (AE)-shelter that emits interference signals that protect communication between legitimate transmitters and legitimate receivers in the AE-shelter. The method includes determining a circular boundary for the AE-shelter; improving the AE-shelter by uniformly placing a number of jammers at the boundary; tuning emitting power of the jammers; and improving a coverage area of the interference signals.

A sound masking system includes a self-amplified loudspeaker emitter unit, with a driver and enlarged ported enclosure, sufficient to provide a frequency range down to a low frequency, such as about 125 Hz. To deliver the power, the power distribution architecture includes audio power amplifiers in the emitter housing of each loudspeaker. Raw power is delivered to each emitter unit through a cable and connectors, such as an Ethernet cable and connectors, in the same cable with the sound masking and audio signals. Inside the emitter units are electronics that efficiently convert the raw power and low level signal to drive the loudspeaker directly. The power comes from a typical desktop power supply, from which the power is combined with the sound masking and audio signals using a power injector unit that distributes the combined power and signals to loudspeakers. The loudspeakers can connect to an individually addressed sound masking network.

A system architecture for managing resources in a communication network comprises in combination at least the following elements: a plurality of radio equipments working in a given frequency band and with identical frequency hopping rules; the radio equipments are managed by a master device; and a radio equipment comprises at least: a radiocommunication module that carries the radiocommunications; a module suitable for tapping, monitoring and intercepting radio signals in the environment and for recording them locally in a database; a module suitable for disrupting non-authorized communications; and a local “3 in 1” management module receiving the orders emitted by the master device, the management module being suitable for controlling the various modules of the radio equipment; a radio-router module; and a tapping and monitoring module.

The disclosure provides a computer-implemented system for establishing a wireless mesh network resistant to degradation induced by deliberate jamming or other electromagnetic interference emanating from point sources within an operating area. The computer-implemented system provides WMN AP locations that minimize disruptions to client coverage caused by jammers, subject to constraints on network service. The computer-implemented system considers jammers placed by an intelligent adversary and identifies the AP locations λ through quantification of an objective function of the general form Z(λ,χ)=Z.sub.coverage(λ,χ)−w Z.sub.flow(λ,χ), where Z.sub.coverage(λ,χ) reflects resulting coverage shortfall, Z.sub.flow(λ,χ) reflects traffic flow within the WMN, and w is a scalar reflecting the relative weight of the two terms. The final set of AP locations λ identifies the locations of APs to create a WMN that is the most robust to the worst possible jamming attack. Such an attack could represent the actions of a rational human opponent, or the worst-case positioning of unintentional interference sources such as civilian radios, other RF devices, or high-voltage electrical devices.

A dynamically-reconfigurable multiband multiprotocol communications jamming system and method is provided that are particularly suited for the generation of effective radio-frequency waveforms/noise output that successively translates up and down the RF spectrum. The system and method are particularly suited for strategically targeting specific frequencies in order to disrupt a communications network or networks, and can be rapidly deployed via delivery platforms, such as artillery and other projectile mechanisms, remote operated vehicles (unmanned aerial, sea or land systems) or targeted air or land delivery via manned assets or automated or robotic support means, or manual delivery by personnel.

A system for near field communications is provided. The system can include a near field generator configured to generate a near field detectable signal comprising information. The system can include a near field detector configured to receive the near field detectable signal and output the information. The system can include an Electro-Magnetic (EM) shield surrounding the near field generator to block EM radio frequency (RF) signals in the vicinity of the near field generator from interfering with operations of the near field generator. The EM shield does not prevent communication of the near field detectable signal between the near field generator and the near field detector. The EM shield can be configured to reduce magnetic field loss from eddy currents in the EM shield as the near field detectable signal passes through the EM shield.