Abstract: This invention provides a system and method for identifying, locating, authorizing by proximity and communicating with equipment and personnel in a facility that generally employs a series of limited range transceivers for location determination and a distributed wireless data network for data transfer. The system employs unique RF transceiver tags on personnel and equipment that are each uniquely identified and registered with a facility control application that oversees activities in the facility. The tags are tracked by RF communication based upon their proximity to one or more fixed-base networked access points and relays (which transfer location data by RF back to access points) within four range zones. Location data on all tags is uploaded periodically to a location server that interfaces with the facility control server.

Abstract: A method is presented for employing radio frequency (RF) identifier (ID) transponder tags (RFID tags) to create a unique identifier, termed an RFID signature, for use within a data processing system with respect to a person or an object. An interrogation signal is transmitted toward a person or an object with which a set of one or more RFID tags are physically associated. A first set of RFID tag identifiers are obtained from an interrogation response signal or signals returned from the set of one or more RFID tags. A mathematical operation is performed on the first set of RFID tag identifiers to generate an RFID signature value, which is employed as an identifier for the person or the object within the data processing system with respect to a transaction that is performed by the data processing system on behalf of the person or the object.

Abstract: An RFID antenna is fabricated according to varying current density requirements of different regions of the antenna. A method such as computer modeling is used to determine the current densities of the antenna regions. In one aspect of the invention, a conductive material is printed to a substrate at varying thickness according to current density requirements of particular antenna regions. In another aspect of the invention, materials of different conductivity are printed to the substrate according to the current density requirements. A material of higher conductivity is printed at an antenna region that requires high current density, and a material of lower conductivity is printed at antenna region that requires lower current density.

Abstract: An RFID tag which has improved radiation/reception characteristics when used in proximity to the human body, and has an antenna which, when stacked with a 13 MHz band RFID tag, does not have an effect on the loop antenna of that tag. An RFID tag assembly comprises a first RFID tag having a coiled loop antenna and a second RFID tag superposed on the first RFID tag, the second RFID tag comprising an antenna formed by a metal member which covers at least a portion of a surface of a dielectric substrate, an electronic part mounted on the metal member, and a member which is provided with the overlapped coiled loop antenna of the first RFID tag housed in the end thereof so as to cover a portion of the antenna formed by the metal member.

Abstract: The invention concerns a radio frequency identification device (RFID) including a chip (12) and an antenna (10) connected together on a support, the antenna being printed onto the support and the support being fixed to an object with an added attachment means. According to the main characteristic, the attachment means overlaps at least once at least one turn of the antenna so that the radio frequency identification device (RFID) is destroyed if the support is detached from the object without the attachment means being removed.

Abstract: An antenna structure capable of determining the direction of a radiofrequency identification (RFID) tag includes a wide-angle antenna disposed within an attenuator that has regions of low attenuation. The attenuator may include a metal plate with holes. In this case, the antenna only detects RFID tags that are aligned with a hole, and hence the direction of the RFID tag is detected. Multiple holes of different sizes can be provided. In this case, if the RFID tag is moving, the direction and speed of movement can be determined from the duration of received RFID signals. For example, a long period of RFID tag signal reception indicates that the tag passed in front of a large hole in the attenuator. The present invention is particularly well suited for use with conveyor belts and in applications where RFID tags move along known paths.

Abstract: An identification device has a band and a non-reusable tamper-resistant fastening arranged to join opposite end regions of the band to fasten it around a limb of a user. A transponder circuit is attached to the band, and is responsive to a received wireless signal. In response to the received wireless signal, the transponder emits a wireless signal representative of information pre-stored in the transponder. An electrically conductive continuous loop on the band extends from the transponder and forms an electrically continuous path along substantially the entire length of the band, the loop being frangible and easily broken in response to an attempt to remove the band from the wearer's limb. Circuitry in the transponder is electrically connected to the loop and arranged to become inoperative and disable the transponder if the loop is broken.

Abstract: A system and method for automatically generating and receiving notifications regarding accesses to documents in a shared repository, where the notifications are filtered such that they are only generated and/or received for accesses that match a personal interest profile of a local user. The personal interest profile of the local user includes a number of keywords determined to be of interest to the local user, as well as a number of important person identifiers associated with other users determined to be important to the local user. The system is operable to provide notifications in response to accesses by important other users to shared documents, including reading of those documents by the important other users.

Abstract: A communications system has first and second units whereby, when a user changes the physical state of the first unit, a message is sent to the second unit to cause the second unit to change to the same state. This change in state can be, for example, a physical squeezing movement or a change in color.

Abstract: A system for detecting and discriminating between water and ice formation on a number of objects, such as aircraft or roadways is described. The system includes an optical element or sensor adapted to receive at least first and second wavelengths of light from a multi-wavelength light source and for outputting attenuated versions of the first and second wavelengths of light. A detector senses and converts the attenuated versions of the first and second wavelengths of light to electrical signals proportional to the light intensities of the first and second wavelengths of light. A processor is coupled to receive and process the electrical signals for determining one or more light intensity values and for actuating one or more indicators corresponding to one of a number of predetermined states of operation of the optical element, including a normal state of operation, a rain state of operation and/or an ice state of operation.

Abstract: A method for implementing a weather alarm in an outdoor computer includes defining atmospheric-pressure data repeatedly, defining altitude data repeatedly and essentially simultaneously with the atmospheric-pressure data, with the aid of a satellite positioning system, and converting both measured variables into the same measurement unit, either pressure or altitude. The difference between the converted variables is determined and is stored as a reference value, the difference between the converted variables is repeatedly monitored, and when the difference changes by more than a preset limit-value relative to the reference value, a weather alarm is given. Also an apparatus for performing the method.

Abstract: An emergency alert message data structure, an emergency alert message processing method and a broadcast receiver are disclosed. When a state of emergency where a channel change to an emergency broadcast channel is required occurs, a transmitting stage includes information regarding the emergency broadcast channel and emergency alert contents in text form in an emergency alert message and transmits the resulting emergency alert message. A receiving stage receives the emergency alert message and determines whether the channel change to the emergency broadcast channel included in the emergency alert message is required. If the channel change to the emergency broadcast channel is determined to be required, the receiving stage changes the current channel to the emergency broadcast channel, and displays the emergency alert contents in text form included in the emergency alert message on a portion of a screen of the emergency broadcast channel in a scrolling manner.

Abstract: A method for reducing false detects may include emitting an infrared light beam from a primary emitter to a primary monitor detector, measuring a first voltage value using a primary receive detector and setting a primary smoke alarm flag corresponding to a primary channel if the first voltage value is above a first threshold value. The method may also include measuring a second voltage value using a secondary receive detector, setting a secondary smoke alarm flag corresponding to a secondary channel if the second voltage value is above a second threshold value and setting an alarm indicating a smoke condition if the primary smoke alarm flag and the secondary smoke alarm flag are set.

Abstract: A power protection system for protection against an electrical transient surge and/or interference. Such a system can be useful in the dispensing of fuel at gas stations, convenience stores, truck stops, and other such locations, for protection of the low voltage signal wires that go from the dispenser to the store. Broadly contemplated are modular arrangements where removal of a corrupted module in a cabinet containing several modules will still keep the general communications circuit intact. Particularly contemplated are modules which include integral fuses and indicator lights.

Abstract: A power strip is providing including a housing coupled to a first end portion of a power supply cord, the housing having an electrical receptacle mounted thereto and connected to the power supply cord, the power supply cord having a second end connectable to a power source. A current sensor is coupled to the power supply cord between the electrical receptacle and the second end for detecting electrical current flow through the power supply cord and providing an output signal that varies in proportion to the current flow through the power supply cord. A processing circuit coupled to the output of the current sensor includes a display device for displaying at least one of the current, voltage, power, and phase associated with the power supply cord at the current sensor. The display device can be remotely coupled to the power strip for positioning the display in a convenient location.

Abstract: A rock bolt includes a hollow body and a gap along a length of the hollow body. At least one strain gauge is affixed to an inner surface of the rock bolt and is accessible from the gap. The rock bolt may include a data logger within the hollow body and coupled to receive signals from one or more strain gauges, and to record these signals in a memory. The data logger may comprise a data port adapted to be accessible from the outside of a bore hole into which the rock bolt is inserted. The data logger also may include at least one of a visual and auditory alarm. A graphic user interface software program can be used to download data from the data logger and set certain operating parameters of the data logger.

Abstract: Condition monitoring of an electrical machine is achieved by using electro-magnetic finite element analysis to analyse the machine based on model parameters corresponding with at least one fault condition. This allows the effect of the fault condition to be predicted. Metrology is used to recover live measurements for comparison with the predictions from the electro-magnetic finite element analysis to identify any fault signatures within the live measurements, in principle allowing those faults to be detected or diagnosed before they become catastrophic.

Abstract: A sensor unit including: two or more individual sensors; and alignment mechanism for aligning at least one of the two or more individual sensors with another sensor or a source to maximize a transmitted signal therebetween. Also provided is a method for maximizing a transmitted signal between sensors and/or sources in a sensor network. The method including: arranging two or more of the sensors in a package; and aligning at least one of the two or more sensors in the package with at least another sensor or a source.

Abstract: Acoustic telemetry systems and methods with surface noise cancellation. One illustrative embodiment may include an acoustic telemetry system comprising a transmitter configured to generate an acoustic information signal that propagates along a drillstring, and a receiver configured to detect an acoustic receive signal from the drillstring and a noise signal from a surface environment. The receiver operates on the acoustic receive signal and the noise signal to produce a modified signal indicative of the acoustic information signal and having a reduced noise content relative to the acoustic receive signal.

Abstract: A pipeline communication system and method includes a pipeline having a surface extending along at least a portion of the length of the pipeline. A conductive bus is formed to and extends along a portion of the surface of the pipeline. The conductive bus includes a first conductive trace and a second conductive trace with the first and second conductive traces being adapted to conformally couple with a pipeline at the surface extending along at least a portion of the length of the pipeline. A transmitter for sending information along the conductive bus on the pipeline is coupled thereto and a receiver for receiving the information from the conductive bus on the pipeline is also couple to the conductive bus.

Abstract: A telemetered characteristic monitor system includes a remotely located data receiving device, a sensor for producing signal indicative of a characteristic of a user, and a transmitter device. The transmitter device includes a housing, a sensor connector, a processor, and a transmitter. The transmitter receives the signals from the sensor and wirelessly transmits the processed signals to the remotely located data receiving device. The processor coupled to the sensor processes the signals from the sensor for transmission to the remotely located data receiving device. The data receiving device may be a characteristic monitor, a data receiver that provides data to another device, an RF programmer for a medical device, a medication delivery device (such as an infusion pump), or the like.

Abstract: A safety alarm system for use on moving vehicles and heavy equipment provides an added level of safety by not only indicating motion, but by adding a distinct audible warning according to a selected sound pattern template when danger is imminent to those in the local area of potential danger. The sound pattern is selected on the basis of signals from various combinations of signals detected from an object detection sensor and an ambient noise level sensor, thereby providing enhanced safety in the work environment.

Abstract: A system and method is disclosed to the elimination of cross talk between inductive loop detector units in a security system. The system includes appropriate devices for assigning different operational frequencies of each loop detector circuit to avoid cross talk. In a further aspect it provides a system and method for determining actual operational frequencies of various loop detector circuits in a security system and for changing the resonant frequencies to eliminate cross talk.

Abstract: A method and system for synchronization of detection loops in a multilane environment. A plurality of loop sensors are arranged in a plurality of lanes such that loop sensors in adjacent lanes are mutually contiguous. A simultaneous synchronization signal is sent to each of the plurality of loop detector controllers, where each loop detector controller is in communication with a loop sensor. The signal causes a scheduling of sampling periods for each loop sensor, such that the sampling period of each loop sensor does not overlap with that of a contiguous loop in an adjacent lane.

Abstract: Red, green and white colored lights are emitted from navigation orientation indicating light emitting devices mounted within a helicopter rotor blade near its tip. The light emissions from such devices are under control to respectively indicate passage of the rotor blade through limited arcuate portions of the travel path of the rotor blade end tip. Operational control over the light emitting devices is effected by data processing of outputs from air-speed responsive sensors on the blade end tip.

Abstract: A process for determining travel through at least one toll road section by at least one vehicle (FAR) by means of a position determination system (POS) which is set up to determine the current position of the at least one vehicle (FAR), whereby positions of the at least one vehicle (FAR) are compared with the position of at least one reference point characteristic for an entrance (AUF) to a toll road section, whereby the orientation (ORI) of the vehicle is determined within a specifiable region (BER) about the entrance (AUF), whereby it is determined whether the orientation (ORI) determined agrees within a specifiable tolerance range with the orientation (ORA) characteristic of entry onto the toll road section.

Abstract: A press key structure comprises two first plates disposed between a casing and a circuit board, wherein one side of each first plate is exposed to the outside of the casing, the other side thereof faces the circuit board and includes a groove, and each of the grooves includes a trigger module disposed at the position corresponding to a first triggering portion on the circuit board, and a second plate includes a pressing portion and two elastic connecting portions, wherein the elastic connecting portions are disposed at two ends of the pressing portion at the positions corresponding to the two first plates respectively, a surface of the pressing portion is exposed to the outside of the casing, the other surface thereof faces a second triggering portion on the circuit board, and the two elastic connecting portions are respectively accommodated in the grooves so as to place the pressing portion at the position between the two first plates and extend the other ends of the elastic connecting portions out from the

Abstract: An ergonomic keyboard as shown in FIG. 3A for use with a stationary palm wherein the keys (15) of the keyboard are actuated only by motion of the joints in the digits. The keyboard may have a thumb region (20), a palm rest region (8) and a hypothenar rest region which are discrete parts and are adjustable relative to one another along a longitudinal axis. Some keys may be actuated by the back surface of the digits. The keyboard may be on an upper portion (2) which is mounted on a base (1) such that three dimensional rotational adjustment is possible between the upper portion and base. The position of the keyboard relative to a user may be adjusted. The spacing of the keys on the keyboard may be spaced at different intervals and have different forces for actuation.

Abstract: The specification and drawings present a new method and apparatus for a touch actuation in an electronic device using a general purpose input board. The input board comprises of a grating of conductors running in one direction (y-lines). Between these conductors there are contacts connected to a grating running in the perpendicular direction a layer below (x-lines). The grating layers are separated by an insulating layer. Various known methods can be used to read the position of, e.g., a conductive actuator touching the input board. The input board can be used as a configurable UI board under a keymat. The input devices on the keymat can be a key, a joystick, a touchpad top membrane, etc. Also, the actuators can be made force-sensitive by detecting a contact surface area. In addition, all components of the general purpose input board can be made of materials substantially transparent to light.

Abstract: An input device includes a plurality of input keys arranged in a matrix of three or more rows and three or more columns; electrodes facing parts of or all surfaces of the input keys that surround intersection of rows and columns formed by the arrangement of the input keys; and an input key detecting unit that identifies operated input keys among the plurality of input keys by combinations of the electrodes having a change in electrostatic capacitance. With this structure, the number of electrodes can be less than that of the input keys.

Abstract: A data encoding apparatus extracts valid data to be encoded from received data and encodes the data, and realigns the encoded data in units of a predetermined data width and outputs the data having each unit of the predetermined data width. A data decoding apparatus extracts valid data to be decoded from received data and realigns the decoded data in units of a predetermined data width and outputs the data having each unit of the predetermined data width.

Abstract: A decoding method for optical storage device, which decodes channel bits upon a disc by partial response maximum likelihood (PRML) detection, is proposed. Unlike the conventional skills, the present method does not decode the detected RF signals directly, but adjusts values of parts of detected RF signals to their original ideal values before channel decoding instead, thereby reducing the decoding error rate of channel bits. The decoding method includes the step of: retrieving a first sequence of RF signals; identifying if the first sequence of RF signals contains a signal combination which satisfies a particular condition; adjusting a plurality of RF signals in the first sequence of RF signals to some pre-determined RF signals' value and then forming a second sequence of RF signals; and decoding the second sequence of RF signals. In a preferred embodiment of the invention, the method is applied to an optical storage system of PR (1,2,2,2,1) channel.

Abstract: A high frequency compensator configured to compensate high frequency component of a digital audio signal comprising a down sampler configured to perform ½ down-sampling for the digital audio signal. An up sampler is configured to perform double up-sampling for an output signal of the down-sampler. A digital low-pass filter is configured to filter an output signal of the up sampler, and to output the filtered digital audio signal.

Abstract: A non-integer CIC interpolation filter is provided for use in sigma-delta digital-to-analog systems, which realizes non-integer interpolation but eliminates the need for coupling of the integrators in the output domain. The present non-integer interpolation filter provides for more attenuation to all of the aliases of the input signal and has eliminated the need of complex computations.

Abstract: Systems and methods for optimizing system performance in variable length decoding systems are described. Embodiments are described in which decode tables are analyzed and elements of the tables sorted by probability of occurrence. Storage of elements can be determined by probability of occurrence and embodiments of the present invention can optimize system efficiency by storing most likely entries into fast-memory and least likely entries in slowest memory. In certain embodiments, a single large table is provided that cannot fit into decoder fast-memory. In some embodiments, individual elements can be optimized for storage in fast-memory by selecting more frequently occurring entries or groups of entries into decoder memory.

Abstract: A circuit for testing an analog-digital converter includes: a subtracter which receives a converted value having a plurality of bits outputted from the analog-digital converter and an expected value having a plurality of bits, the subtracter calculating a difference value having a plurality of bits between the converted value and the expected value; and a logical operation circuit which receives the difference value, the logical operation circuit performing an exclusive-NOR operation between adjacent bits in the plurality of bits constituting the difference value, thereby outputting an exclusive-NOR value having a plurality of bits.

Abstract: A self-calibrating continuous-time delta-sigma modulator determines whether time constants of its internal integrators are too large or too small by injecting a calibrating sequence into the modulator and examining a correlation between the calibrating sequence and a modulator output sequence. Then the time constants of the internal integrators are adjusted accordingly. In one embodiment, the correlation is exploited based on matching a noise transfer function of the modulator using an adaptive filter based on a least mean square (LMS) algorithm.

Abstract: A two phase, second order capacitance-to-digital (CD) modulator includes a first stage sigma-delta integrator that forms charge packets as a function of sensor capacitance during an auto-zero phase and integrates the packets during an integration phase to produce an output voltage. The first stage integrator holds its output voltage during the auto-zero phase, so that a second stage sigma-delta integrator can sample the first stage output voltage during the auto-zero phase and integrate the sampled voltage during the integration phase.

Abstract: A delta sigma modulator which employs a plurality of accumulators with non-power-of-2 modulus. The accumulators may consist of a primary non-power-of-2 modulus accumulator and a secondary non-power-of-2 modulus accumulator. The number of bits in the primary accumulators affects the frequency resolution of the resultant delta sigma fractional N frequency synthesizer and can be the minimum number of bits required by the resolution specification. The secondary accumulator integrates the carry outputs of its corresponding primary accumulators. This integration results in attenuating the dc content of the modulator output by a factor equal to the modulus of the secondary accumulators and may require compensation in the recombination block.

Abstract: A bias circuit includes a digital to analog converter (D2A) generating an output representing a voltage level for tuning an analog signal. The D2A is coupled to a primary register frame that is one of a plurality of register frames forming a data chain. The plurality of register frames are serially linked and data within the data chain is shifted among the plurality of register frames. Through a time domain multiplexing scheme, the D2A can be shared by control knobs of the equalization circuit. The bias circuit includes a decoder also coupled to the primary register frame. An output enable logic module is also included. The output enable logic module determines when the primary register has a complete data set as the data within the data chain is shifting according to the clock period. A method for adjusting a signal through a bias circuit is also provided.

Abstract: A method of matching dynamic elements includes sequentially selecting first unit elements corresponding to a value of first digital data among M unit elements in a first direction, the M unit elements being for converting sequentially inputted digital data to an analog signal; checking whether a reference unit element is selected; checking a value of a LSB of the first digital data when the reference unit element is selected; sequentially selecting second unit elements corresponding to a value of second digital data inputted next to the first digital data among the M unit elements in a second direction opposite to the first direction when the value of the LSB of the first digital data is a first value; and sequentially selecting the second unit elements in the first direction when the value of the LSB of the first digital data is a second value.

Abstract: A DA conversion device includes the following elements. A higher-bit current source cell portion includes uniformly weighted higher-bit current source cells to generate an identical constant current. A lower-bit current source cell portion includes a lower-bit current source cells that are weighted to generate 1/two-to-the-power-of-certain-numbers constant currents. A constant current source selection controller includes a lower-bit controller having a scaler that uses clocks scaled down to 1/two-to-the-power-of-certain-numbers to select the lower-bit current source cells, and a higher-bit controller having shift registers and using a signal indicating a carry bit or a borrow bit used in the lower-bit controller to sequentially activate shift outputs of the shift registers, and uses the shift outputs to select the higher-bit current source cells. Constant current outputs of the selected current source cells are added and output so that an output current corresponding to the digital input signal is obtained.

Abstract: The linearity of switched-capacitor, pipeline digital to analog converters is improved by balancing the settling behavior of its pre-charge switches. In more detail, a switched capacitor DAC includes a number of substantially identical cells, one cell for each bit of an input digital word. A number of switch driver circuits are used to apply respective switch control signals to turn respective switches on and off. Advantageously, the switch control signals differ by an amount determined to equalize the gate-to-source voltage difference between different switches.

Abstract: An amplifier-based system having pulsed output includes an amplifier for amplifying a time varying voltage signal to produce an output voltage signal. A voltage-to-current (V-I) converter converts the output voltage signal into a current signal. An output stage including a current integrator integrates the current signal to generate an integrated voltage. An amplitude to time converter generates a pulse train from the integrated voltage, wherein a timing of the pulses in the pulse train represents the original time varying voltage signal. The pulse train representation permits transmission and accurate remote reconstruction of the original time varying voltage signal, such as signals generated by electrodes implanted inside a subject, including neural signals.

Abstract: The present invention provides an adaptive, intelligent transform based Analog to Information Converter (AIC) for wideband signals by directly converting an analog signal to information (e.g., features, decisions). This direct conversion is achieved by (i) capturing most of the information of a wideband signal via hardware/software implemented mathematical transformations, (ii) effectively removing unwanted signals such as jammer and interfere from the input signal, and (iii) using novel algorithms for highly accurate decision making and feature extraction (e.g., high probability of detection with low probability of false alarm). The jump in the improvement over today's state-of-the-art is in terms of effective and optimum signal information extraction at high-speed.

Abstract: An analog to digital converter (ADC) with interference rejection capability and method thereof are disclosed. The ADC includes a threshold generator, a comparator circuit, a counter and an integrator. By comparing a signal with positive and negative threshold signals from the threshold generator, the comparator circuit converts the signal from analog to digital based on the result of the comparison. The counter counts a percentage of the digital signal and generates a bit signal based on the counted percentage. In response to the bit signal, the integrator supplies a control signal to the threshold generator to regulate the positive and negative threshold signals so as to maintain the counted percentage at a predetermined percentage threshold.

Abstract: An N-bit analog to digital converter includes a reference ladder, a track-and-hold amplifier connected to an input voltage, a coarse ADC amplifier connected to a coarse capacitor at its input and having a coarse ADC reset switch controlled by a first clock phase of a two-phase clock, a fine ADC amplifier connected to a fine capacitor at its input and having a fine ADC reset switch controlled by a second clock phase of the two-phase clock, a switch matrix that selects a voltage subrange from the reference ladder for use by the fine ADC amplifier based on an output of the coarse ADC amplifier, and wherein the coarse capacitor is charged to a coarse reference ladder voltage during the first clock phase and connected to the T/H output during the second clock phase, wherein the fine capacitor is connected to a voltage subrange during the first clock phase and to the T/H output during the second clock phase, and an encoder that converts outputs of the coarse and fine ADC amplifiers to an N-bit output.

Abstract: Automotive vehicle including a radar transceiver each including a heterodyne active IMPATT multiplier module arranged to receive a signal from a VCO, a first balance mixer arranged to receive a signal from a VCO, a second balance mixer arranged to receive a signal from a receive antenna and the IMPATT multiplier module and derive a first intermediate frequency signal, a first amplifier for amplifying the output of the second balance mixer and providing the amplifier output to the first balance mixer, and a second amplifier for amplifying the output of the first balance mixer. The vehicle also includes a processor which receives output from the second amplifier of each transceiver and generates a control signal for controlling one or more vehicular components based on the output from the second amplifier(s). The components can be part of a collision avoidance system, blind spot monitoring system and the like.

Abstract: An attack is activated in a receiver amplifier of an interrogator whenever an amplified input signal exceeds an attack threshold voltage value Vatt, and the receiver amplifier at least during a waiting period, the length of which preferrably equals the double length of the longest time interval between adjacent pulses in a transponder data wave packet, after the end of the attack does not respond in the sense of setting the gain. However, the amplifier responds with a decay activated after the lapse of the waiting period, which started when the instantaneous amplified signal value for the last time after the end of the attack exceeded a waiting threshold voltage level Vw. The decay rate is of the same order of magnitude as the attack rate. The improved method for automatically setting the gain renders it possible that the interrogator receiver within the non-contacting identification system practically does not change the essential characteristics of the input signal.

Abstract: A method for determining an angle for each of two RF signals at different frequencies and offset from each other. The average angle of a composite signal is obtained from the two RF signals over a frequency difference period by averaging the frequency difference period. The average angle of the composite signal is the dominant signal's angle. The smaller signal's angle is then calculated from the dominant signal's angle, an angle centroid, and the signal voltages for the two RF signals.