Systems, apparatuses, and methods are described for a privacy blocking device configured to prevent receipt, by a listening device, of video and/or audio data until a trigger occurs. A blocker may be configured to prevent receipt of video and/or audio data by one or more microphones and/or one or more cameras of a listening device. The blocker may use the one or more microphones, the one or more cameras, and/or one or more second microphones and/or one or more second cameras to monitor for a trigger. The blocker may process the data. Upon detecting the trigger, the blocker may transmit data to the listening device. For example, the blocker may transmit all or a part of a spoken phrase to the listening device.

In order to detect a replay attack in a speaker recognition system, at least one feature is identified in a detected magnetic field. It is then determined whether the at least one identified feature of the detected magnetic field is indicative of playback of speech through a loudspeaker. If so, it is determined that a replay attack may have taken place.

System and for signal re-transmission including a channelizer, a signal-effect-processor and a controller. The signal-ef-fect-processor includes a plurality of sub-band-processors and a summer. The channelizer receives a sampled Intermediate-Frequency signal exhibiting a first sampling-rate. The channelizer produces a plurality of sub-band-signals, each associated with a respective sub-band of the Intermediate-Frequency signal. Each sub-band-signal exhibit a second sampling-rate lower than the first sampling-rate. Each of at least one selected sub-band-processor receives a respective sub-band-signal, introduces at least one effect to the respective sub-band-signal, and increases the sampling-rate of the respective sub-band-signal to the first sampling-rate, thereby producing a respective affected sub-band re-transmit signal. Each selected sub-band-processor is further provides the respective affected sub-band re-transmit signal to a respective input of the summer. The summer sums the inputs thereof to produce a wideband affected re-transmit signal. The controller selects the selected sub-band processor and controls settings of the at least one effect.

This application relates to an apparatus and method for generating a jamming signal, and a communication system. In one aspect, the method may include converting binary bits of a first communication signal to be transmitted and obtaining at least one codeword matched previously to the binary bits. The method may also include generating a second communication signal by superimposing a first conversion signal being obtained by converting the first communication signal to an up-chirp signal and a second conversion signal being obtained by converting the first communication signal to a down-chirp signal. The method further include generating a pseudo jamming signal by computing the second communication signal and the codeword.

Systems, apparatuses, and methods are described for a privacy blocking device configured to prevent receipt, by a listening device, of video and/or audio data until a trigger occurs. A blocker may be configured to prevent receipt of video and/or audio data by one or more microphones and/or one or more cameras of a listening device. The blocker may use the one or more microphones, the one or more cameras, and/or one or more second microphones and/or one or more second cameras to monitor for a trigger. The blocker may process the data. Upon detecting the trigger, the blocker may transmit data to the listening device. For example, the blocker may transmit all or a part of a spoken phrase to the listening device.

A vehicle includes: receiver(s), a timer counting time, memory, and processor(s) configured to: receive a timestamped signal from a fob; compare the timestamp to a time window; reject the timestamp if the timestamp is outside the time window; expand the time window with the counted time; compute the time window as a trigonometric function of the counted time and a predetermined angle.

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.

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.

Systems, apparatuses, and methods are described for a privacy blocking device configured to prevent receipt, by a listening device, of video and/or audio data until a trigger occurs. A blocker may be configured to prevent receipt of video and/or audio data by one or more microphones and/or one or more cameras of a listening device. The blocker may use the one or more microphones, the one or more cameras, and/or one or more second microphones and/or one or more second cameras to monitor for a trigger. The blocker may process the data. Upon detecting the trigger, the blocker may transmit data to the listening device. For example, the blocker may transmit all or a part of a spoken phrase to the listening device.

Systems, apparatuses, and methods are described for a privacy blocking device configured to prevent receipt, by a listening device, of video and/or audio data until a trigger occurs. A blocker may be configured to prevent receipt of video and/or audio data by one or more microphones and/or one or more cameras of a listening device. The blocker may use the one or more microphones, the one or more cameras, and/or one or more second microphones and/or one or more second cameras to monitor for a trigger. The blocker may process the data. Upon detecting the trigger, the blocker may transmit data to the listening device. For example, the blocker may transmit all or a part of a spoken phrase to the listening device.