Abstract: Methods, apparatus and systems for wirelessly monitoring a micro motion of an object 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 and a motion of an object in the venue.

Abstract: Methods, systems, and computer program products for lane detection. An image processing module is trained by machine learning, and used to generate correspondence mapping data based on an image pair of a first and second images. The correspondence mapping data defines correspondence between a first lane boundary group of the first image and a second lane boundary group of the second image. An image space data block of image space detection pairs is then generated based on the correspondence mapping data, and a three-dimensional lane detection data block generated using triangulation based on first and second parts of the image space data block corresponding to respective first and second members of the image space detection pairs.

Abstract: Various embodiments utilize application-based processing parameters to dynamically configure a radar-based detection system based upon an operating context of an associated device. A first application with execution priority on a device dynamically configures the radar-based detection system to emit a radar field suitable for a first operating context associated with the first application. The first application can also dynamically configure processing parameters of the radar-based detection system, such as digital signal processing parameters and machine-learning parameters. In some cases, a second application assumes execution priority over the first application, and dynamically reconfigures the radar-based detection system to emit a radar field suitable to a second operating context associated with the second application.

Abstract: Techniques are generally described for controlling a camera to capture video based on one or more auxiliary motion sensors. First data indicative of motion may be received from a first motion sensor at a camera. In some examples, the first motion sensor may have a first field-of-view. Second data indicative of motion may be received from a second motion sensor at the camera device. In some examples, the second motion sensor may have a second field-of-view different than the first field-of-view. A determination may be made that the first data temporally corresponds to the second data. In some examples, an image sensor of the camera may capture first image data in response to the first data indicative of motion and the second data indicative of motion.

Abstract: An apparatus for protecting an entrance to a protected area comprises a magnetic sensor to measure an ambient magnetic field or gradient within a first zone of sensitivity at a non-magnetic sensor means adapted to detect the presence of objects within a primary detection zone, a signal processing circuit arranged in communication with the magnetic sensor apparatus and nonmagnetic sensor apparatus, and a warning device operable by an output signal from the signal processing circuit, the warning device adapted to provide an alarm. The signal processing circuit identifies temporal variations due to the movement of a ferromagnetic object within the ambient magnetic field and correlates them with instances in which the non-magnetic sensor means detects the presence of an object in its detection zone, and causes the alarm to operate in the event that the correlation is indicative of the presence of a ferromagnetic object in the primary detection zone.

Abstract: An apparatus for protecting an entrance to a protected area comprises a magnetic sensor to measure an ambient magnetic field or gradient within a first zone of sensitivity at a non-magnetic sensor means adapted to detect the presence of objects within a primary detection zone, a signal processing circuit arranged in communication with the magnetic sensor apparatus and non-magnetic sensor apparatus, and a warning device operable by an output signal from the signal processing circuit, the warning device adapted to provide an alarm. The signal processing circuit identifies temporal variations due to the movement of a ferromagnetic object within the ambient magnetic field and correlates them with instances in which the non-magnetic sensor means detects the presence of an object in its detection zone, and causes the alarm to operate in the event that the correlation is indicative of the presence of a ferromagnetic object in the primary detection zone.

Abstract: A motion detector and a method for operating the motion detector including a radio frequency (RF) transmission circuit, an RF reception circuit, and a controller that is electrically coupled to the RF transmission circuit and the RF reception circuit. The controller is configured to control the RF transmission circuit to generate an RF signal and control the RF reception circuit to receive a reflected RF signal from a target object in a predetermined time for reception after transmission of the RF signal. The controller is further configured to control the RF reception circuit to generate a Doppler signal indicative of a distance between the target object and the motion detection system based on the reflected RF signal. The controller is further configured to adjust a sensitivity of the RF reception circuit during the predetermined time for reception and activate an indicator based on the magnitude of the Doppler signal.

Abstract: An ultrasonic probe includes, a transducer transmitting and receiving ultrasonic waves, and converting ultrasonic signals into voltage signals and vice versa, a first circuit configured to transmit pulse voltage signals to the transducer and receive the voltage signals from the transducer, a second circuit configured to convert the voltage signals received from the first circuit into digital values from analog values, a battery unit configured to supply electric power to the first circuit and the second circuit, and a substrate being provided with the transducer, the first circuit and the second circuit, the first circuit being disposed on a first surface of the substrate, and the second circuit being disposed on a second surface opposite to the first surface of the substrate.

Abstract: Disclosed herein, among other things, are methods and apparatus for wireless electronics using a MEMS switch for a hearing assistance device. The present application relates to a hearing assistance device configured to be worn by a wearer. The hearing assistance device includes a housing for electronics of the hearing assistance device, including wireless electronics. The wireless electronics include a plurality of radio frequency (RF) MEMS switches, in various embodiments. A hearing assistance processor is adapted to process signals for the wearer of the hearing assistance device. In various embodiments, the hearing assistance device includes an antenna, and a switchable capacitor bank configured for tuning the antenna, the switchable capacitor bank including one or more of the plurality of RF MEMS switches. The plurality of RF MEMS switches include an electrostatically deformed RF MEMS membrane, in an embodiment. Different configurations and approaches are provided.

Abstract: According to an exemplary embodiment, an ultrasound apparatus for beamforming with a plane wave transmission may comprise a transceiver connected to a transducer array having at least one transducer element, and at least one processor. The transceiver transmits at least one substantially planar ultrasonic wave into a target region at one or more angles relative to the transducer array, and receives one or more signals responsive from the transducer array. The at least one processor applies a fast Fourier transform (FFT) to the one or more signals from each of the at least one transducer element and calculates at least one frequency within a frequency region, and applies an inverse FFT to at least one produced frequency data.

Abstract: A radar system includes a transmitter configured to generate a series of electromagnetic pulses, and a receiver configured to receive return signals reflected by an object of interest from the series of electromagnetic pulses. A phase processor is operatively connected to the output of the receiver and configured to extract phase data as a function of time from the received return signals, convert the extracted phase data to the frequency domain, and analyze the phase data to identify phase changes indicative of one or more types of motion, such as complex or simple dynamic motion of the object of interest.

Abstract: A vehicle detection system includes a sensor mounted to establish a light curtain along a portion of a roadway, and a control unit operatively coupled with the sensor to detect a vehicle on the roadway. The light curtain defines a first zone and a second zone within the first zone such that detection of the vehicle in the first zone followed by detection of the vehicle in the second zone indicates a correct direction of travel of the vehicle, and detection of the vehicle in the second zone prior to detection of the vehicle in the first zone indicates a wrong direction of travel of the vehicle.

Abstract: An object detection method using ultrasonic waves includes: emitting a plurality of ultrasonic signals sequentially according to a time interval; sensing a sound wave formed by each of the ultrasonic signals to generate a reflected signal; and analyzing the reflected signal to detect at least one reflection object. It can be clearly known whether a reflection object is appearing, moving and the moving direction by the method.

Abstract: Described herein is a passive wireless resonating non-linear sensor that is typically based on a ferroelectric varactor. The sensor replies its data at an intermodulation frequency when a reader device illuminates it at two closely-located frequencies. Furthermore, described herein is a general intermodulation read-out principle for passive wireless sensors. A sensor utilizes a mixing element, such as a varactor and it can be equipped with a capacitive, inductive, or resistive sensor element. When the sensor is illuminated with signals with two frequencies it replies the sensor data at an intermodulation frequency.

Abstract: Methods, apparatus and systems for implementing link training for next-generation high-speed Ethernet links including a 100 Gbps Ethernet link. Training frames are transmitted from a transmit port to be received at a receive port, with each training frame comprising a frame marker portion, a control channel portion, and a training pattern portion. Four-level signaling including a low level signal, first and second intermediate level signals, and a high level signal is implemented for the training pattern portion of the training frame using a pseudo-random bit pattern, while only the low and high level signals are employed for the frame marker and control channel portions of the training frame. The four-level signaling may employ PAM4 encoding. Examples of apparatus and systems in which the link training techniques may be implemented include blade servers and network routers and switches.

Abstract: A doppler sensor includes a doppler signal generation unit and a determining unit. The doppler signal generation unit serves to transmit an electric wave to a detection range and receiving electric waves from a detection range, and generating a doppler signal based on a transmission signal used in transmitting the electric wave and a reception signal obtained from the received electric waves, and the determining unit serves to determine whether or not there exists a human body in the detection range through a spectrum analysis using a peak frequency, which is a frequency having the highest intensity in a difference spectrum obtained by subtracting a background spectrum from the spectrum of the doppler signal.

Abstract: The object is to appropriately control a frequency of performing the link process. A link device detects a movement of a user based on a result of a link process for linking an outlet and an electronic appliance used by the user. The link device also detects a scheduled event from a schedule of the user. In case an event is detected, the link device calculates a difference between a scheduled time when the event will occur and the current time, and increases a frequency of performing the link process as the calculated difference gets smaller. In case the movement detection unit does not detect a movement of the user by the scheduled event time, the link device increases the frequency of performing the link process larger than a current frequency being used.

Abstract: An LED-based light can be installed in a conventional light fixture. The LED-based light can include a sensor operable to output a first signal indicative of whether an area of one or more of the rooms is in an occupied state or a non-occupied state, and the LED-based light can also include an LED controller operable to control at least one LED in the light in response to the first signal. Additionally, the LED-based light can include a transmitter operable to output a second signal indicative of whether the area is in the occupied state or the non-occupied state to a building environment regulator.

Abstract: The present invention provides a new non-invasive technique for organ, e.g., heart and lung, monitoring. In at least one embodiment of the invention, a subject is radiated with a non-harmful and relatively low power electromagnetic source diagnostic signal normally associated with a communications protocol such as, but not limited to a version of the IEEE 802.11(x) family of protocols in the 2.4, 3.6, or 5 GHz spectrum bands. After passing through the patient, a return signal is acquired from the patient and compared to the original source signal. The differences between the source and modified signals are then analyzed to monitor the heart, e.g., measure heart rate and detect defects within the heart, and the lung. For example, using Doppler Effect principles, heart rate and motion can be measured from the differences in frequency, phase, and/or wavelength between the source signal and the modified signal reflected back from the heart moving within the patient.

Abstract: An ultrasonic occupancy sensor for detecting presence or absence of an occupant in a space includes an ultrasonic receiving circuit having a synchronous rectifier that allows the circuit to detect small-magnitude ultrasonic waves having a Doppler shift. The sensor comprises an ultrasonic transmitter for transmitting ultrasonic waves at an ultrasonic operating frequency, and a controller that drives the transmitting circuit with complementary drive signals to control the ultrasonic operating frequency. The synchronous rectifier receives the drive signals from the controller and rectifies an amplified input signal to generate a rectified signal, which is filtered by a filter to generate a filtered signal. The controller receives the filtered signal and determines that the space is occupied if the magnitude of the filtered signal exceeds a threshold.

Abstract: The present invention provides a new non-invasive technique for organ, e.g., heart and lung, monitoring. In at least one embodiment of the invention, a subject is radiated with a non-harmful and relatively low power electromagnetic source diagnostic signal normally associated with a communications protocol such as, but not limited to a version of the IEEE 802.11(x) family of protocols in the 2.4, 3.6, or 5 GHz spectrum bands. After passing through the patient, a return signal is acquired from the patient and compared to the original source signal. The differences between the source and modified signals are then analyzed to monitor the heart, e.g., measure heart rate and detect defects within the heart, and the lung. For example, using Doppler Effect principles, heart rate and motion can be measured from the differences in frequency, phase, and/or wavelength between the source signal and the modified signal reflected back from the heart moving within the patient.

Abstract: A system capable of monitoring an area and detecting a disturbance with the area. The system has a plurality of ultra-wide band radio frequency tags, each of the tags including a digital signal processing module configured to monitor changes in radio frequency multipath properties of received packets transmitted by at least one other of the tags. Changes in the radio frequency multipath properties may be caused by a disturbance indicative of an object in the vicinity of the tags. A corresponding method is also disclosed.

Abstract: The invention relates to a method for monitoring the integrity of a Doppler transceiver, where a Doppler transceiver comprises a transmitter unit, a receiver unit and a mixer unit, where a signal is transmitted from the transmitter characterized in that the transmitted signal is at least partially coupled into a modulation unit, where the coupled signal is modulated according to certain parameters, and the modulated signal is transmitted to the receiver unit. The invention also relates to a Doppler transceiver comprising a transmitter unit and a receiver unit having at least one antenna (34, 54, 66, 74, 90, 96) and a mixer unit (38, 64), characterized in that it also comprises a modulation unit (48, 70, 86, 106) which is electrically disconnected to the antenna (34, 54, 66, 74, 90, 96).

Abstract: A mobile object detecting apparatus includes first radiation detecting means; and second radiation detecting means for radiating an electromagnetic wave having the same frequency as the electromagnetic wave radiated by the first radiation detecting means such that the radiated electromagnetic wave passes near a point in the first radiation detecting means from which the electromagnetic wave is radiated, and detecting a standing wave which is generated due to reflection of the radiated electromagnetic wave at an object; wherein a distance, over which the electromagnetic wave radiated by the first radiation detecting means travels until it reaches near the first radiation detecting means, corresponds to a distance of an integral multiple of a wave length of a half cycle of the electromagnetic waves radiated by the radiation detecting means plus a wave length of a predetermined period which is smaller than the half cycle.

Abstract: A sensor system for a host vehicle may detect whether another in-path vehicle is turning. The sensor system may include a transmitter, a receiver and a controller. Signals may be emitted by the transmitter over a detection area. The emitted signals may reflect off an object vehicle in the detection area and be received by the receiver. The receiver may include a number of channels, each corresponding to a different region of the detection area. The sensor system may determine whether the in-path vehicle is turning and in what direction based on the reflected signals received at each channel.

Abstract: In an example embodiment, an access point (AP) uses out-of-band signaling on a single non-DFS (Dynamic Frequency Selection) frequency band radio in an N-radio system to synchronize information with neighboring APs and to learn about their radio interfaces. This enables the AP to be able to acquire information about neighbor APs on different frequency bands and to build and maintain mesh routing structures while minimizing backhaul down-time.

Abstract: Systems and methods to determine motion parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, a method implemented in a radio frequency identification (RFID) system includes determining a motion parameter of the RFID tag based on detecting a Doppler frequency shift in a radio frequency signal received from the RFID tag.

Abstract: A moving object detection system is provided with an existence detection part, an integrating part and an existence judgment part. Based on first and second detection signals, the existence detection part calculates a rotation angle of each transition factor that is obtained from the first and second detection signals and rotates around the origin in a two-dimensional coordinate system. The existence detection part is configured so that the rotation angle becomes less than 90 degrees. The integrating part integrates each rotation angle to obtain an integrated angle. The existence judgment part judges whether or not a moving object approaching or leaving a receiver of the device exists in a detection area based on the integrated angle and a threshold angle.

Abstract: A method and apparatus are provided for automatically testing microwave instruction detection modules of a security system. The method includes the steps of detecting intruders within a protected space by monitoring a Doppler output of a signal extraction circuit coupled to a microwave transceiver module, varying a frequency of direct current power pulses applied to the microwave transceiver module, detecting a difference in magnitude of the Doppler output of the signal extraction circuit over the varied frequency and comparing the detected difference with a fault threshold level.

Abstract: A motion detector system includes the ability to detect motion through the use of a Doppler radar sensor or a combination of PIR sensors and a Doppler radar sensor. The system includes an outdoor light fixture having one or more lamps and a housing coupled to the outdoor light fixture. The housing includes a Doppler radar sensor and a microprocessor for analyzing the signals received by the Doppler radar sensor. Alternatively, the housing includes a combination of PIR sensors and a Doppler radar sensor and a microprocessor for analyzing the signals received from these sensors. The lamps in the light fixture are activated when either the PIR sensor or the Doppler radar sensor generates a signal indicating motion within the monitored area. Alternatively, the lamps can be activated when either the PIR sensor or the Doppler radar sensor senses predetermined number of motion activities over a limited time period.

Abstract: An ultrasonic occupancy sensor for detecting presence or absence of an occupant in a space includes an ultrasonic receiving circuit having a synchronous rectifier that allows the circuit to detect small-magnitude ultrasonic waves having a Doppler shift. The sensor comprises an ultrasonic transmitter for transmitting ultrasonic waves at an ultrasonic operating frequency, and a controller that drives the transmitting circuit with complementary drive signals to control the ultrasonic operating frequency. The synchronous rectifier receives the drive signals from the controller and rectifies an amplified input signal to generate a rectified signal, which is filtered by a filter to generate a filtered signal. The controller receives the filtered signal and determines that the space is occupied if the magnitude of the filtered signal exceeds a threshold.

Abstract: A method for localizing a person in surroundings equipped with fixed electrical appliances includes measuring an electromagnetic field radiated by one or more of these fixed electrical appliances with a magnetometer carried by the person, identifying a fixed appliance operating near the magnetometer by comparing the measured field with pre-recorded magnetic signatures. Each pre-recorded magnetic signature is associated with an electrical appliance present in the surroundings. The person is then localized at least in part based on pre-recorded items of information that correspond to localization, in the surroundings, of the fixed electrical appliance as identified by its magnetic signature.

Abstract: A intrusion detection system includes a first sensor device having a first transmission circuit unit that transmits a modulation wave of a first transmission spectrum diffusion signal to a first transmission leakage transfer passage and a second sensor device having a second transmission circuit unit that transmits a modulation wave of a second transmission spectrum diffusion signal to a second transmission leakage transfer passage. The signal interval of the first transmission spectrum diffusion signal is the same as the signal interval of the second transmission spectrum diffusion signal. The first transmission spectrum diffusion signal and the second transmission spectrum diffusion signal are shifted in frequency so that the first transmission spectrum diffusion signal does not overlap with the second transmission spectrum diffusion signal.

Abstract: The described method characterizes scattering objects in a wireless channel. The present invention determines non-equally spaced path delays and Doppler parameters for a plurality of scattering objects in a wireless channel. More particularly, a frequency-to-time transform applied to a plurality of OFDM pilot samples received over a plurality of OFDM symbol periods generates a set of non-equally spaced path delays and a set of associated complex delay coefficients. Further, a time-to-frequency transform applied to the complex delay coefficients determined for one path delay over multiple OFDM symbol periods generates a set of Doppler parameters comprising a plurality of non-equally spaced Doppler frequencies and their corresponding scattering coefficients for that path delay.

Abstract: Slaves are respectively provided corresponding to electric devices, measure, in real time, power usage states and disposed positions of the electric devices to transmit to a master. The master detects operational states of electric devices on operation based on power usage states received from the slaves, and detects a positional relation between electric devices on operation based on disposed positions of the electric devices. Then, the master estimates the number of residents in the house by determining achievability of operational states of electric devices based on the detected operational states and positional relation of electric devices.

Abstract: A motion detector system includes the ability to detect motion through the use of a Doppler radar sensor or a combination of PIR sensors and a Doppler radar sensor. The system includes an outdoor light fixture having one or more lamps and a housing coupled to the outdoor light fixture. The housing includes a Doppler radar sensor and a microprocessor for analyzing the signals received by the Doppler radar sensor. Alternatively, the housing includes a combination of PIR sensors and a Doppler radar sensor and a microprocessor for analyzing the signals received from these sensors. The lamps in the light fixture are activated when either the PIR sensor or the Doppler radar sensor generates a signal indicating motion within the monitored area. Alternatively, the lamps can be activated when either the PIR sensor or the Doppler radar sensor senses predetermined number of motion activities over a limited time period.

Abstract: An apparatus for checking for the presence of objects and in particular containers, comprising a transmitting device which has a sound signal generation unit for emitting a sound signal, and a receiving device which is arranged relative to the transmitting device in such a way that a sound signal emitted by the transmitting device and transmitted through air can be received by the receiving device. According to the invention, at least the transmitting device or the receiving device has a housing, wherein at least one region of this housing is suitable for emitting or for receiving sound signals.

Abstract: A method and apparatus are provided for detecting an intruder. The method includes the steps of receiving an echo from opposing sides of a curtain line extending through the secure area, determining a difference between the received echoes, determining a phase difference of the signal and generating an alarm when the determined phase changes sign between successively received echoes.

Abstract: A method and apparatus are provided for automatically testing microwave instruction detection modules of a security system. The method includes the steps of detecting intruders within a protected space by monitoring a Doppler output of a signal extraction circuit coupled to a microwave transceiver module, varying a frequency of direct current power pulses applied to the microwave transceiver module, detecting a difference in magnitude of the Doppler output of the signal extraction circuit over the varied frequency and comparing the detected difference with a fault threshold level.

Abstract: A motion sensing method and apparatus includes a housing enclosing a microwave motion sensor including an antenna, and a security system. The antenna may be a patch antenna which includes microwave radiating elements for transmitting and receiving a microwave signal for sensing motion. A reflector is attached to the housing and positioned above the antenna for downward shaping of the microwave signal. The microwave radiating elements together with the reflector provide a radiation pattern where a main beam is transmitted in a direction orthogonal to a surface of the antenna and a sided lobe is transmitted downward in amplitude below the microwave motion sensor. An alarm circuit indicates when the microwave sensor detects motion in armed mode, and a masking circuit indicates when the microwave sensor detects motion in a mask zone when the security system is unarmed. A second sensor may be positioned beneath the microwave motion sensor.

Abstract: A method of detecting a moving target within a predefined protected region with a microwave motion detector, by transmitting microwave frequency signals and receiving the microwave frequency signals reflected by a target. A target distance is then determined from the received microwave frequency signals, and a target angle is determined from the received microwave frequency signals. Then, a target location is determined from the target distance and the target angle, and an alarm condition is set if the target location is within the predefined protected region.

Abstract: A method for detecting an intruder in a protected space that uses a microwave frequency sensor to determine an accurate distance measurement to the intruder. The accurate distance measurement reduces the false alarms typically associated with microwave frequency sensors due to motion outside the protected space and vibration within the protected space. The motion detector transmits three microwave frequency signals of different frequencies in order to eliminate an ambiguity problem when determining the accurate distance measurement. The accuracy of the intruder distance measurement may be determined with greater resolution by reiteratively transmitting and evaluating microwave frequency signals of different frequencies. The motion detector of the present invention may include a PIR sensor.

Abstract: In a CW radar system for detecting motion behind a wall involving modulation of the radar transmission, means are provided to interrupt the CW wave when motion is detected and to use the same radar transmitter to transmit a serial digital message to a remote monitoring receiver. The encoding can include a receiver wakeup message to turn on the receiver only when motion has been detected. In one embodiment, a microprocessor is used to detect when motion exists behind a wall and to provide a tailorable message to modulate the radar's transmitter in the period when the CW signal from the radar is turned off after motion detection.

Abstract: The present invention is an alarm system that includes a dual technology motion sensor. The dual technology sensor includes a PIR sensor with a PIR detection pattern and a Doppler microwave frequency motion detector with a detection pattern wider than that of the PIR sensor. The microwave detector's processing circuitry distinguishes motion beyond the PIR detection pattern, and limits the microwave detector's field of view to match the PIR detector's detection pattern. The microwave detector has a transmitting antenna, two receiving antennas, and processing circuitry for processing received signals. The microwave detector's processing circuitry uses phase information from the two receiving antennas to distinguish motion beyond the PIR detection pattern.

Abstract: An alarm filter (22) for use in a security system (14) to reduce the occurrence of nuisance alarms receives sensor signals (S1-Sn, Sv) from a plurality of sensors (18, 20) included in the security system (14). The alarm filter (22) produces an opinion output as a function of the sensor signals and selectively modifies the sensor signals as a function of the opinion output to produce verified sensor signals (S1?-Sn?).

Abstract: A motion detector utilizing a low microwave frequency that penetrates dry, non-metallic barriers and detects motion by sensing a Doppler shift in the received signal that has been reflected off of aqueous or metallic objects is disclosed. It is a battery powered hand-held pocket-sized device that includes a microwave motion sensing module that preferably operates continuously at a single frequency, with a single antenna for both transmitting and receiving microwave signals. Circuitry converts the Doppler shift in the received signal into a voltage that is then modified so that it can be immediately displayed to the user on an indicator meter. It is also contemplated that the device include a data logging module for storing the modified signal, another type of data, or both. The device can also include a means for charging the batteries and an on-off switch to conserve power while the device is not in use.

Abstract: A method of automatically calibrating a motion detector and a motion detector adapted for calibration using the method. The method comprises setting the motion detector to a calibration mode, waiting a preset period of time for the installer to walk to the furthest distance, receiving a Doppler signal generated by motion at the furthest distance from the microwave motion detector within the protected area, measuring an amplitude of the Doppler signal and storing a motion detection threshold for the microwave motion detector. The motion detection threshold is a proportional to the measured amplitude.

Abstract: A microwave direction of travel detector and method of detecting the direction of an intruder in a protected region. The microwave direction of travel detector transmits and receives, by a microwave transceiver a microwave signal directed toward a protected area. The microwave return signal is modulated by a moving target to produce a Doppler signal. The microcontroller monitors the output of the amplifier chain and stores the signal and compares it with previously stored signals. If the amplitude is increasing or decreasing over a preset time period, this would indicate that the target it approaching or receding respectively and an alarm would be generated by the microcontroller.

Abstract: A method and apparatus are provided for detecting an intruder. The method includes the steps of receiving an echo from opposing sides of a curtain line extending through the secure area, determining a difference between the received echoes, determining a phase difference of the signal and generating an alarm when the determined phase changes sign between successively received echoes.

Abstract: An apparatus for monitoring an access portal through an enclosure around a hazard comprises a line-scan camera mounted above the portal so that its linear field of view extends along a generally opposite threshold of the portal and can detect electromagnetic radiation reflected from an object passing through the portal. The apparatus distinguishes signals from the camera corresponding to items that are intended to pass through the portal for example on a conveyor from signals corresponding to items, particularly intruders that are not intended to pass through the portal. The apparatus preferably comprise an elongate sodium discharge lamp mounted above the portal and provided with a reflector so that monochromatic light therefrom is concentrated in a narrow strip extending along the threshold and the camera is sensitive only to this monochromatic light.