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.

Some embodiments relate to a method for repelling a detectable drone, whose flight control and/or whose drone flight path can be influenced by repulsion measures, wherein a repulsion space is defined as a part of the airspace, and wherein the flight control and/or the drone flight path of a drone located in the repulsion space is influenced.

Disclosed are systems and methods for disabling a battery in an un-manned aerial vehicle. The system includes a battery containing lithium; a battery disable unit; and a processor configured to: receive a disable command; and transmit the disable command to the battery disable unit to activate the battery disable unit to cause the battery to malfunction.

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.

There is provided an apparatus comprising an antenna (105) configured to receive a signal from a global navigation satellite system, wherein the antenna includes a first feed and a second feed; a hybrid coupler (110) including a first hybrid input, a second hybrid input, a first hybrid output, a second hybrid output, and wherein the first hybrid output is shifted in phase by 90 degrees relative to the second hybrid output; a variable phase shifter (150) including a shifter input and a shifter output, hybrid output; and a combiner (155) including a first combiner input, a second combiner input, and a combiner output, wherein the first combiner input is coupled to the shifter output, and the second combiner input is coupled to the second hybrid output, and wherein the combiner output is provided to detection circuitry (197).

According to an example aspect of the present invention, there is provided a method, comprising: receiving, by a positioning information receiver, an authentication information element from a positioning information source, requesting verification of authenticity of the positioning information source on the basis of the authentication information element and a distributed ledger of verified positioning information sources, and establishing a cryptographic session with the positioning information source for receiving positioning information in response to receiving an indication of verification of authenticity of the positioning information source.

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 peak suppression monitor is coupled to a tracking channel. The peak suppression monitor facilitates receiving, from the tracking channel over a time period, real-time correlation data derived from a global navigation satellite system signal. The real-time correlation data having one or more peaks. Predicted correlation data corresponding to the real-time correlation data is determined based on historical correlation data. A presence of spoofing within the real-time correlation data is identified based on one or more peaks of residual correlation data. The residual correlation data including a comparison between the real-time correlation data and the predicted correlation data. Spoofing detecting data is generated based on the presence of spoofing and the residual correlation data. The generated spoofing detecting data to the tracking channel is provided for further mitigation or a notification identifying the presence of spoofing is provided to a user.

A circular grazing system for poultry and/or livestock. The circular grazing system including a center pivot structure installed at a field. The center pivot structure may have a center pivot axis. The field may be a poultry and/or livestock grazing field. The circular grazing system for poultry and/or livestock may include an enclosure for containing poultry and/or livestock. The enclosure may extend generally radially from the center pivot structure to a circumference of the field. The enclosure may be rotably coupled to the center pivot structure such that the enclosure rotates around the center pivot axis.

An aircraft flight control apparatus includes a flight track acquiring unit and a determining unit. The flight track acquiring unit is configured to measure a position of an aircraft to acquire a flight track of the aircraft. The determining unit is configured to determine, when an own-aircraft deviation amount gradually increases, whether the aircraft receives a spoofed signal as a satellite positioning system signal, on the basis of the own-aircraft deviation amount. The own-aircraft deviation amount is an amount of deviation of the flight track acquired by the flight track acquiring unit from a scheduled flight route of the aircraft.