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.

Disclosed herein is an architecture for a Digital Capacity Centric Distributed Antenna System (DCC-DAS) that dynamically manages and distributes resources in different locations where there is demand for capacity. The DCC-DAS also allows for the routing of resources to other applications such as location finding devices, jamming devices, repeaters, etc.

The present invention is generally related to a device for providing wireless jamming signals in a delimited geographic area. The device is comprised of an on/off initiation module that allows the user to turn-on or turn-off the device, and initialize the jamming wireless signals device, a central controller module to distribute and analyze the information of the system, a signal transmitter device to transmit the jamming signals, a device to calculate distances to obtain the distances between the said signal transmitter and the objects in the delimited geographic area. The jamming device once is turned on calculates the distances and the power where to transmit the jamming signals to cover the required geographic area. This device will be capable of jamming one or more types of wireless signals at the same time such as Wi-Fi, cell phones and other wireless signals.

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.

The subject matter herein field is for multiple and complimentary systems in the structure of a cellular device case so as to provide sound jamming and/or sound insulation, and/or powered noise cancellation as means of restriction the entry of useful sound into the microphone(s) of cellular smartphone devices, as a means of citizen counter-action of the “constant surveillance” characteristics inherent in the “always on,” microphone systems as described under Background of the Subject matter, above.

In various embodiments, the present invention presents a physical layer (PHY) authentication technique for implantable medical devices (IMDs) that does not use existing methods of cryptology. Instead, a friendly jamming mechanism is established and malicious attempts by adversaries are prevented, without sharing any secured information, such as secret keys. In addition to ensuring authentication, the invention also provides advantages in terms of decreasing processing complexity of IMDs and enhances overall communications performance.

A security signal transmission method performed by a first communication node includes estimating a radio channel between the first communication node and a second communication node; classifying all subcarriers into a first subcarrier group for transmitting a data signal and a second subcarrier group for transmitting a jamming signal based on estimated channel information; generating data symbol(s) by allocating the data signal to subcarriers of the first subcarrier group; generating jamming symbol(s) by allocating the jamming signal to subcarriers of the second subcarrier group; generating a first control symbol to which a first control signal is mapped, the first control signal including a first reference value used to restore the data symbols at the second communication node; and transmitting the data symbol(s), the jamming symbol(s), and the first control symbol to the second communication node.

This application relates to a jamming signal generating apparatus. In one aspect, the jamming signal generating apparatus includes a signal analyzer configured to perform measurement and analysis of a radar reception signal, and a radio frequency (RF) source signal output device configured to receive the radar reception signal and to output a video signal by reflecting the measurement and the analysis. The jamming signal generating apparatus may also include a frequency up converter configured to output a jamming signal and a jamming transmission signal measurement device configured to receive the video signal and the jamming signal and to obtain a jamming to signal ratio (JSR).