Patent classifications
H04K3/224
Radio frequency interference mitigation with adaptive local oscillator
Various schemes for mitigating radio frequency (RF) interference are described, wherein an adaptive local oscillator (LO) is utilized. A receiver measures a jamming indicator which indicates a total power within a receiving band of the receiver. If the jamming indicator indicates a presence of substantial in-band interference, the receiver may program the LO to a different frequency and/or adjust a bandwidth of a filter accordingly to reject or reduce the interference. The receiver may adjust the LO and/or the filter repeatedly until the interference is rejected to a point that de-sense to the signal intended to be received is satisfactorily mitigated. The receiver may restore the LO and the filter to a default setting when the jamming indicator indicates that the interference is no longer present.
WIRELESS COMMUNICATION SYSTEM WITH DISCRIMINATION BETWEEN EXTRANEOUS RECEIVED SIGNALS
A wireless communication system having base stations and remotely located terminal units. The base stations and the remotely located terminal units communicate data over operational wireless communication links assigned to respective sub-channels having tiles separated by frequency and time. Detectors for analysing extraneous received signals in unassigned tiles of the communication links discriminate between a first type of extraneous signals detected in unassigned tiles of one sub-frame and also detected in other unassigned tiles, and a second type of extraneous signals detected in the unassigned tiles but not detected in other unassigned tiles. The reaction of the base stations is different based on the type of extraneous signals.
Selective Jamming Detection Based on Comparing Two Or More Signal Measurement Quantities
Methods implemented by a processor in a wireless device for detecting the presence in a network of a jammer or non-benign entity that targets physical layer channels in a communication network are disclosed. Various embodiments may determine a first signal measurement quantity based on a first physical layer communication, determine a second signal measurement quantity based on a second physical layer communication, determine a difference between the first signal measurement quantity and the second signal measurement quantity, determine whether the difference between the first signal measurement quantity and the second signal measurement quantity satisfies a threshold, determine whether a jammer or non-benign entity is present in the network in response to determining that the difference between the first signal measurement quantity and the second signal measurement quantity satisfies the threshold, and perform a mitigation operation in response to determining that a jammer or non-benign entity is present in the network.
Jammer Detection and Mitigation
Methods for detecting and responding to detecting a non-benign network entity (e.g., jammer, etc.) that targets physical layer channels in a communication network. A wireless device may receive a physical downlink control channel (PDCCH) and a demodulation reference signal (DMRS) from a network entity, determine radio signal strength indicator (RSSI) for the received PDCCH, determine a signal to noise ratio (SNR) for the DMRS, determine whether the RSSI satisfies a first threshold, and determine whether the DMRS SNR satisfies a second threshold.
Automatic External RF Gain Calibration and Continuous Jamming Measurement
A system and method provide automatic RF path gain calibration independent of RF interference levels to preserve solution trust capabilities. After a system is powered ON, or a new antenna is attached (hot swap), a smart antenna assembly combined with a jammer power estimator within an RF receiver functions to autonomously measure internal gains within the RF path, calibrate the new antenna installation, and thereby measure a level of interference associated with the external environment from that point forward. A controller commands the antenna calibration retrieving antenna details and RF path gain calibration while measuring local jamming at the receiver input. Should the controller determine a level of jamming effectiveness is present, it offers a user a display of the local jamming levels enabling the user accurate theater decision making regarding the accuracy and availability of desirable signal.
SYSTEM AND METHOD FOR TRIGGERING AN ALARM DURING A SENSOR JAMMING ATTACK
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.
Closed-loop transmission rate control
Transmitting a signal from a transmitter. A method includes identifying a threshold spectral flux density for a given physical location. The method further includes, as a result of identifying the threshold spectral flux density, transmitting a signal at a power level causing the signal to be below the spectral flux density at the given physical location, the signal being transmitted at a data rate. The method further includes receiving feedback from a receiver indicating the signal-to-noise ratio of the signal at the receiver. The method further includes adjusting the data rate of the signal based on the feedback. The method further includes continuing transmitting the signal at the adjusted data rate and power level.
Spread spectrum signature reduction
A system and method for secure communications is disclosed which includes a processor(s) of a first appliqu spreading an uplink signal of a user from user equipment, where the first appliqu is coupled to the user equipment, and where the user equipment is connected to a mobile network. The processor(s) frequency shifts the spread uplink signal to maintain orthogonality over the mobile network.
CLOSED-LOOP TRANSMISSION RATE CONTROL
Transmitting a signal from a transmitter. A method includes identifying a threshold spectral flux density for a given physical location. The method further includes, as a result of identifying the threshold spectral flux density, transmitting a signal at a power level causing the signal to be below the spectral flux density at the given physical location, the signal being transmitted at a data rate. The method further includes receiving feedback from a receiver indicating the signal-to-noise ratio of the signal at the receiver. The method further includes adjusting the data rate of the signal based on the feedback. The method further includes continuing transmitting the signal at the adjusted data rate and power level.
Blocking jamming signals intended to disrupt communications
Jamming systems uses wireless signals (e.g., radio waves) to deliberately prevent a target from accurately receiving desired wireless signals. The examples herein disclose an anti-jamming system that mitigates an effect that jamming signals have on a radio receiver. To do so, the anti-jamming system generates a plasma shield in a region of space between the target and the jamming system. Plasma is opaque to electromagnetic energy meaning that radio signals, lasers, microwave energy, and the like are unable to pass through the plasma, and instead, are absorbed by the plasma. As such, the jamming signals emitted by the jamming system are absorbed by the plasma shield and do not interfere with the target's radio receiver.