Methods, systems, and apparatus, including computer programs encoded on a storage device, for triggering an alarm during a sensor jamming attack. In one aspect, a monitoring system sensor unit is disclosed that includes a sensor, a communication unit configured to communicate with a monitoring system using a range of frequencies, and a jamming detection unit. The jamming detection unit may include a processor and a computer storage media storing instructions that, when executed by the processor, cause the processor to perform operations. The operations include detecting a sensor jamming event, selecting a different form of communication other than the range of radio frequencies for the communication unit to communicate with the monitoring system, and providing, to the communication unit, an instruction to communicate with the monitoring system using the form of communication, wherein the communication unit may communicate, to the monitoring system using the form of communication, the sensor data.

A communication system including an analog front end and an automatic gain controller. The analog front end includes at least one amplifier for amplifying a received analog signal and an analog to digital converter that converts the analog signal to digital samples. The automatic gain controller includes comparator circuitry, counter circuitry, and a gain controller. The comparator circuitry compares each of the digital samples with an upper threshold and a lower threshold. The counter circuitry counts a high count number of the digital samples having magnitudes that are greater than the upper threshold during each count window and counts a low count number of the digital samples having magnitudes that are less than the lower threshold during the count window. The gain controller adjusts a gain of the at least one amplifier by an amount based on the high count number and the low count number.

A secure wireless transceiver, such as a link 16 transceiver, receives signals using an antenna array having an SOC associated with each antenna element in the array. The SOC's digitize and channelize received data for transmission to a message nulling system that mitigates jamming. The antenna array can be conformal, and can replace an existing Link 16 blade. The disclosed transceiver can be a modified CMN-4 transceiver with digitizing and channelizing moved to the SoC's, and replaced by the nulling system. The transceiver uses applicable TRANSEC information to assign received data to the logical Link 16 channels before nulling, and embodiments apply nulling only to channels of interest, thereby improving the nulling and reducing side lobes. Embodiments distinguish between desired and unwanted signals based on known Link 16 signal features and/or situational awareness, rather than signal amplitudes, thereby enabling nulling of even weak jamming signals.

The system and method of global positioning system (GPS) anti-jam (AJ) AJ antennas utilizing a circular array of patch antennas. In some cases the circular array is conformal. The elements are single patch, dual band (L1/L2) and are linearly polarized. A mode former and progressive phase tapers are used.

A technology is described for mitigating global positioning system (GPS) spoofer signals. A potentially spoofed GPS signal received via an antenna coupled to a GPS receiver can be identified. The potentially spoofed GPS signal can be applied to a spoofer signal nulling loop to generate a set of spoofer nulling weights. The set of spoofer nulling weights can produce a direction vector associated with the potentially spoofed GPS signal. The direction vector can be compared to a beamsteering vector. The potentially spoofed GPS signal can be determined as being a spoofer GPS signal when a misalignment between the direction vector and the beamsteering vector is above a defined threshold. The spoofer GPS signal can be converted to a spoofer mitigation signal that is applied to satellite track channels of the GPS receiver. The spoofer mitigation signal can produce a spatial null in a direction of the spoofer GPS signal.

A system and method for nulling or suppressing interfering signals directed toward moving platforms based, at least in part, on dynamic motion data of the moveable platform is provided. The system may be an interference nulling system carried by a moveable platform and may include an antenna array including two or more antenna elements that generates at least one initial steerable null radiation pattern, dynamic motion data logic that determines dynamic motion data of the moveable platform; and update logic that updates the at least one initial steerable null radiation pattern based, at least in part, on the dynamic motion data. The at least one updated steerable null radiation pattern is directed toward a direction from which interfering signals are being transmitted from an interfering signal source.

Methods, systems, and apparatus, including computer programs encoded on a storage device, for triggering an alarm during a sensor jamming attack. In one aspect, a monitoring system sensor unit is disclosed that includes a sensor, a communication unit configured to communicate with a monitoring system using a range of frequencies, and a jamming detection unit. The jamming detection unit may include a processor and a computer storage media storing instructions that, when executed by the processor, cause the processor to perform operations. The operations include detecting a sensor jamming event, selecting a different form of communication other than the range of radio frequencies for the communication unit to communicate with the monitoring system, and providing, to the communication unit, an instruction to communicate with the monitoring system using the form of communication, wherein the communication unit may communicate, to the monitoring system using the form of communication, the sensor data.

A GNSS receiver comprises an input, at least one front end processor, and an interference mitigation unit. The input is configured to receive from a wireless communication module a control signal comprising timing information, the timing information indicating one or more transmission times during which the wireless communication module wirelessly transmits data. The at least one front end processor is configured to capture a set of data samples from a received GNSS signal and store the data samples in a memory, each sample captured at a corresponding sample time. The interference mitigation unit is configured to configured to identify data samples of the set of data samples that have a sample time that corresponds with one or more transmission times as candidate samples for interference.

A method is provided for controlling communication in wireless charging. The method comprises: controlling wireless power transfer with a device; receiving a communication signal from the device; generating a jamming signal based on the communication signal from the device; and applying the jamming signal to the communication signal to obtain a jammed communication signal. A device is also provided for controlling communication in wireless charging. The device is configured to control wireless power transfer and receive a communication signal. The device comprises: a jamming circuit configured to generate a jamming signal based on the received communication signal, wherein the device is further configured to apply the jamming signal to the received communication signal to obtain a jammed communication signal.

An access point in a wireless network communicates wirelessly with one or more client devices over a channel that includes a plurality of subchannels. Radar is detected on a first subchannel of the plurality of subchannels. It is determined to puncture the first subchannel, based on the detecting the radar on the first subchannel and based on one or more puncturing factors. The first subchannel is punctured, the puncturing comprising muting one or more subcarriers on the first subchannel.