A navigation method based on satellite positioning data and non-satellite positioning data includes the following steps of: computing a first reference navigation that is hybridised on the basis of non-satellite positioning data and satellite positioning data, the first reference navigation being reset on the satellite positioning data; performing a statistical analysis of the positional corrections provided by the first reference navigation and deducing therefrom the existence or the absence of a deception operation of the satellite signal receiver. A navigation system for implementing this method is disclosed.

An apparatus is disclosed for jammer detection. In example aspects, the apparatus includes a wireless transceiver configured to be connected to multiple antennas. The wireless transceiver is configured to transmit a radar transmit signal using a first antenna of the multiple antennas. The wireless transceiver is also configured to receive a radar receive signal via a second antenna of the multiple antennas, with the radar receive signal associated with the radar transmit signal and comprising a jamming signal component. The wireless transceiver is additionally configured to adjust at least one transmission parameter based on a detected presence of the jamming signal component. The wireless transceiver is further configured to transmit an uplink signal based on the adjusted at least one transmission parameter.

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 radio device for the transmission of information has a radio-device control unit, at least one antenna, an antenna switchover unit and at least one radio unit. The radio device provides a static radio unit and at least one dynamic radio unit, wherein at least two radio units are radio-ready, so that, by means of a switchover signal of the radio-device control unit, a switchover between the radio-ready radio units can be implemented in a real-time manner.

An apparatus and method for protecting a communication device of a railroad car is provided. The apparatus includes an antenna portion configured to include main antennas and an auxiliary antenna, a main receiver configured to check a magnitude of a received signal transferred through the main antennas of the antenna portion, an auxiliary receiver configured to check a magnitude of a received signal transferred through the auxiliary antenna of the antenna portion, and a controller configured to compare the magnitude of the signal received by the main receiver and the magnitude of the signal received by the auxiliary receiver, determine whether there is a jamming signal according to a comparison result, and take a preset countermeasure when it is determined that there is a jamming signal.

Techniques and apparatus for wake-up radio (WUR) operations are provided. One technique includes communicating with one or more wireless devices via a first radio operating on a first channel. A WUR is operated on a second channel different from the first channel. A wireless device may receive an indication of the second channel to use for monitoring for WUR transmission, and monitor for a WUR transmission on the second channel after receiving the indication.

Methods and apparatus for determining if a signal of interest, for example, a licensed signal having or exceeding a predetermined field strength, is present in a wireless spectrum and/or which facilitates such a determination are described. The signal of interest maybe, e.g., a television signal or a wireless microphone signal using licensed television spectrum. The predetermined field strength may be specified or by a government regulation or rule.

Various examples are provided for jamming avoidance response (JAR), and photonic implementations thereof. In one example, a method includes generating optical pulses that correspond to raising envelope of a beat signal associated with an interference signal and a reference signal; generating optical spikes that correspond to positive zero crossing points of the reference signal; and providing a phase output that indicates whether the beat signal is leading or lagging the reference signal, the phase output based at least in part upon the optical spikes. An adjustment to a reference frequency can be determined based at least in part upon the optical pulses and the phase output. In another example, a JAR system includes photonic circuitry to generate the optical pulses; photonic circuitry to generate the optical spikes; and photonic circuitry to provide the phase output. A logic unit can determine the adjustment to the reference frequency.

Method and apparatus are disclosed for detection and protection against jam intercept and replay attacks. An example disclosed key fob includes a first wireless transceiver tuned to communicate via a first frequency band, second wireless transceiver tuned to communicate via a second frequency band, and a communicator. The first frequency band is different than the second frequency band. The example communicator sends a first message via the first wireless transceiver in response to activation of a first button. Additionally, the example communicator, in response to not receiving a second message via the second wireless transceiver, provides an alert.

According to some embodiments, a method performed by a network node comprises receiving a plurality of radio signal samples; estimating parameters for a first hypothesis function, the first hypothesis function hypothesizing that that the plurality of radio signal samples only contains background noise; estimating parameters for a second hypothesis function, the second hypothesis function hypothesizing that that the plurality of radio signal samples contains background noise plus one or more radio pulses; performing a log-likelihood ratio test for the first hypothesis function and the second hypothesis function; and based on the log-likelihood ratio test, determining whether a radio pulse is present in the plurality of radio signal samples.