A method for first path acceptance for secure ranging includes determining a Channel Impulse Response (CIR) of a communication channel for a plurality of channel taps. Each channel tap corresponds to a respective one of a plurality of time slots of the CIR, wherein the CIR includes a plurality of estimated CIR values. A statistical characteristic is extracted from the estimated CIR values within a temporal range of the channel taps. The statistical characteristic is compared to a reference value to detect a distance decreasing attack.

A system (1) is configured to cause a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and/or a first reception characteristic, e.g. by lighting devices (31-37), detect whether changes in said first set of radio frequency signals are caused by a human (49) presence, detect whether the changes in the first set of radio frequency signals have a further cause, and cause a second set of one or more radio frequency signals to be transmitted with a second transmission characteristic and/or received with a second reception characteristic upon detecting that the changes in the first set of radio frequency signals have a further cause. The system is further configured to identify the further cause based on changes in the second set of radio frequency signals and provide output comprising the further cause or in dependence on the further cause.

A system and a method are provided for achieving long range, over the horizon (OTH), persistent surveillance, alerting, tracking and situational awareness against small, low radar cross section moving targets. The system and method use one or more tethered unmanned arial systems, or unmanned arial vehicles, to lift components including a radar antenna to a height above nearby obstacles or much higher. The system and method can also be used for subsurface radar detection and tracking applications, as well as communications with submarines.

A monitoring system for monitoring a monitoring area according to one or more embodiments may include a first sensor for detecting movement of a moving object in the monitoring area, a second sensor for determining entry and exit of a person in the monitoring area, and a control device connected to the first sensor and the second sensor. When the first sensor detects movement of the moving object, the control device is configured to determine entry and exit of a person in the monitoring area by referring to a detection result by the second sensor.

The disclosed FMCW radar system is configured to achieve a wide synthetic bandwidth of operation and a high range resolution. The disclosed FMCW radar system includes a receiver that combines the intermediate frequency (IF) components of multiple narrowband receivers to achieve the millimeter-scale range resolution. The disclosed FMCW radar system can be easily scaled, which enables it to be deployed in large arrays of antennas in order to attain high angular resolution. Additionally, the operation frequency of the disclosed FMCW radar system enables millimeter level cross-range resolution. In this manner, accurate estimation of the location and/or velocity of the objects within the local-sensing range (and potentially beyond) can be achieved.

Methods, apparatus and systems for periodic or transient motion detection, e.g. fall event detection, based on wireless signals are described. In one example, a described system comprises: a transmitter configured for transmitting a first wireless signal through a wireless multipath channel of a venue; a receiver configured for receiving a second wireless signal through the wireless multipath channel; and a processor. The second wireless signal differs from the first wireless signal due to the wireless multipath channel that is impacted by a target motion of an object in the venue. The processor is configured for: obtaining a time series of channel information (TSCI) of the wireless multipath channel based on the second wireless signal, computing a time series of spatial-temporal information (STI) of the object based on the TSCI, and detecting the target motion of the object based on the time series of STI (TSSTI).

The present invention relates to a security surveillance microwave sensor having a reduced false report rate by means of biological signal detection, which monitors and determines a malfunction state or a false alarm generated by environmental factors by detecting humans, animals or objects approaching within a predetermined distance using a microwave signal. The present invention may extend the monitoring distance of security surveillance, set an IF frequency band disturbed by a human body, amplify the IF frequency or use a change in the voltage level to extend the monitoring distance, manage a monitoring state by double-checking transmission and reception of security signals, and reduce the false report rate by distinguishing the false alarms or the malfunction state of the sensor.

A fall detection system includes a radar that generates emitting radio waves and receives reflected radio waves from a person under detection, a data generator that generates a point cloud according to the reflected radio waves, an area determining device that determines a sub-area of a detecting area in which the person under detection lies, and a classifier that determines whether the person under detection falls according to the point cloud. The classifier adaptively processes the point cloud with different methods according to sub-areas as determined by the area determining device respectively to determine whether the person under detection falls.

System, methods, and other embodiments described herein relate to sensing interactions of a passenger with components within a vehicle. In one embodiment, a method includes acquiring, from a radar of a vehicle, radar data about a passenger cabin of the vehicle. The method includes determining a current state of the passenger cabin according to the radar data. The method includes, responsive to identifying that the current state indicates that a passenger satisfies a threshold in relation to an unpermitted action, generating a response that counters the unpermitted action.

A vehicle-interior monitoring apparatus for a vehicle includes a sensor and a determiner. The sensor is configured to output a millimeter radio wave toward a vehicle cabin of the vehicle and detect a millimeter reflection wave from an in-vehicle object including an occupant in the vehicle cabin of the vehicle and baggage in the vehicle cabin of the vehicle. The determiner is configured to determine a type of the in-vehicle object in the vehicle cabin of the vehicle based on a detection level of the millimeter reflection wave detected by the sensor. The determiner is configured to perform a determination, the determination including determining that the in-vehicle object is either one of a child as the occupant or the baggage based on a tendency of a change in the detection level of the millimeter reflection wave detected by the sensor.