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).

A radio frequency (RF) jamming device includes a differential segmented aperture (DSA), a jammer source outputting a jamming signal at one or more frequencies or frequency bands to be jammed, and RF electronics that amplify and feed the jamming signal to the DSA so as to emit a jamming beam. The DSA includes an array of electrically conductive tapered projections, and the RF electronics comprise power splitters configured to split the jamming signal to aperture pixels of the DSA. The aperture pixels comprise pairs of electrically conductive tapered projections of the array of electrically conductive tapered projections. The RF electronics further comprise pixel power amplifiers, each connected to amplify the jamming signal fed to a single corresponding aperture pixel of the DSA. The RF jamming device may include a rifle-shaped housing, with the DSA mounted at a distal end of the barrel of the rifle-shaped housing.

A technique for tamper protection of incoming data signal to an electronic device is disclosed. An intentional interference signal is generated and modulated onto the incoming data signal as one composite input signal, to prevent unauthorized acquisition of valid data from the incoming data signal. The magnitude of the interference signal is adjusted to correspond to the magnitude of the incoming data signal, thereby preventing an attacker from properly differentiating the two different signals and/or decoding the valid data from the composite input signal. Once the composite input signal is safely received within the device, the interference signal can be filtered out in either analog mode or digital mode.

Methods, systems, and devices for wireless communications are described. A base station may transmit, to a user equipment (UE), a control message that includes an identification of a set of protection levels corresponding to different degrees of physical layer security for securing communications between the UE and the base station. The base station may transmit, to the UE, an indication of an identified protection level of the set of protection levels to be used by the UE for securing the communications between the UE and the base station. The UE may communicate with the base station in accordance with the identified protection level.

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.

The invention concerns a vehicle tracking network including a plurality of subscriber vehicles and a control-center; and systems and methods for tracking vehicles, which are subscribers to such vehicle tracking network. In certain implementations, the method for tracking a subscriber vehicle includes the following operations carried out at the subscriber vehicle: monitoring operation of one or more services related to at least one of a wireless network communication service and positioning service associated with the subscriber vehicle; upon detecting a failure in at least one of said services, generating a corresponding distress signal encoded to be identifiable by other subscriber vehicle(s) of the vehicle tracking network; and broadcasting the encoded distress signal such that it is detectable by one or more of the other subscriber vehicles of the vehicle tracking network, which are located in the vicinity of the subscriber vehicle broadcasting the distress signal. Another subscriber vehicle(s), which receive the distress signal, may thereby initiate automatic notification of the condition of the vehicle broadcasting the distress signal to the control center.

A method of phrase extraction for ASR models includes obtaining audio data characterizing an utterance and a corresponding ground-truth transcription of the utterance and modifying the audio data to obfuscate a particular phrase recited in the utterance. The method also includes processing, using a trained ASR model, the modified audio data to generate a predicted transcription of the utterance, and determining whether the predicted transcription includes the particular phrase by comparing the predicted transcription of the utterance to the ground-truth transcription of the utterance. When the predicted transcription includes the particular phrase, the method includes generating an output indicating that the trained ASR model leaked the particular phrase from a training data set used to train the ASR model.

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 system and method to prevent eavesdropping by a device. An anti-eavesdrop component is installed on the device. The anti-eavesdrop component is configured to actively prevent the device from capturing audio from the environment. In response to installing the anti-eavesdrop component, the device recognizes the anti-eavesdrop component as a primary audio input for the device. The anti-eavesdrop component then proceeds to block the device from capturing outside audio by injecting noise or otherwise interfering with the primary audio input.

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.