Abstract: The naturally occurring residual charge of a dielectric is utilized to establish a static electric field adapted to be disturbed by a conductive member upon occurrence of an event, such as, for example, the passage of a vehicle tire over the conductive member. Disturbance of the electric field results in the generation of a pulse that can be monitored. A traffic sensor for monitoring the number and speed of vehicles traveling in multiple lanes of a roadway employing dielectrics with naturally occurring residual charge includes a housing containing a cavity, a conductive mounting bar adapted to fit within the cavity, at least two sensing elements including the dielectrics mounted on the mounting bar so as to generate a signal when impacted by a vehicle tire. A transmission cable connects with the sensing elements for transmitting the electric signals generated by the sensing elements to analyzing equipment for evaluating, displaying, and recording the data generated by the sensing elements.

Abstract: A vehicle detector for installation on the surface of a multi-lane road, comprising at least a coaxial detector cable provided with a central conductor, a metallic cladding and a filler material between the cladding and the conductor. The coaxial detector cable comprises at least one region which is referred to as the active region and in which the filler material is mechanoelectric, and also comprises at least one adjoining region which is referred to as a neutral region and in which the filler material is neither mechanoelectric nor potentially mechanoelectric.

Abstract: A system and method for transferring historic and instantaneous diagnostic data relating to performance of an inductive loop vehicle detector 10 is disclosed and claimed. The aforementioned date is gathered over a period of time, updated and stored in a detector unit 14 forming part of the system. The stored data is then used repeatedly to modulate visible light emitted by a light emitting device 22 on the unit 14 at such a rate that the data would not be discernible to a human. The data is received by a portable data reading device 24 which is brought into optical communication with the device 22.

Abstract: An improved body sensing device capable of precisely sensing a living body at a standstill by discriminating the living body from other substances than the living body. An oscillator provided with a detection coil oscillates a high frequency signal. As there is no object or exists baggage or the like near the detection coil, the oscillator oscillates and generates a high frequency signal at a high level to be detected by a detector for turning on a transistor of a controller. As there exists a human body near the oscillator, the oscillation stops and the input signal from the detector to the transistor is extremely lowered, so that the transistor is turned off.

Abstract: A vehicle detector for detecting a moving vehicle traversing a predetermined roadway includes a coil antenna for detecting electromagnetic radiation inherently generated and emitted by the vehicle as it traverses the predetermined path and producing a first signal. A low noise amplifier receives and amplifies the first signal and outputs an amplified first signal to a differential full wave amplitude modulation envelope detector and produces a second signal. A high pass filter having a predetermined cutoff frequency is connected to receive the second signal and output only third signals having a magnitude proportional to the electromagnetic signal being detected. A converter circuit converts the third signals to a digital signal, the converter circuit including a switching comparator having a source of a stable voltage reference level and outputting a fourth signal.

Abstract: A detector system filters the effects of periodic noise such as magnetic flux from nearby power lines or other periodic sources. The detector system further adapts in the case that the system incorporates microloops for the inductive sensors. The detector system further counts multiple vehicles while in presence mode. The detector system also logging of vehicle data and system faults.

Abstract: A detector for detecting a characteristic and a speed of a vehicle includes a first magnetic field sensor for generating a first analog signal indicative of changes in magnetic field strength adjacent the first sensor in response to the vehicle passing. A differentiating circuit differentiates the first analog signal and produces a first output that changes binary state in response to detecting a predetermined change in the differentiated first analog signal. A counter accumulates values at a predetermined rate and a microprocessor stores values of the counter corresponding to each change in the binary state of the first output of the differentiating circuit. The microprocessor converts the stored counter values into a first time series profile corresponding to changes in the first output of the differentiating circuit and accumulates and stores a count of a characteristic of the passing vehicle based on the first time series profile.

Abstract: A railroad crossing traffic warning system for alerting a motorist approaching a railroad crossing to the presence of an oncoming train. The system comprises a series of magnetometer sensor probes buried in the right-of way adjacent to a railroad track at predetermined distances from the railroad crossing. These sensors provide a signal to a controller unit when the presence of a train is sensed. The controller unit first determines the speed at which the oncoming train is traveling and the time it will take for the train to reach the crossing and then activates an improved warning apparatus at a predetermined amount of time before the train reaches the crossing.

Abstract: The period T.sub.nv of an oscillator signal is measured. A number N.sub.meas of cycles of the oscillator signal is determined based upon the measured oscillator period T.sub.nv and upon a desired minimum change in inductance .DELTA.L (sensitivity) which will result in an object being detected. The N.sub.meas cycles of the oscillator signal represent a measurement period. The length of the measurement period, defined by N.sub.meas oscillator cycles, is periodically determined. The length of the measurement period is compared to a reference value. An output, based upon the results of the comparison, is provided. Thereafter, the desired minimum change in inductance .DELTA.L (sensitivity) may be automatically adjusted by determining an average magnitude change in inductance .DELTA.L.sub.ave caused by a plurality of vehicles. The number N.sub.meas of oscillator cycles, which define the measurement period, is recalculated based upon the average magnitude change in inductance.

Abstract: A security system that includes an inductive sensor commonly known as a "proximity sensor" or "variable reluctance sensor", an alarm unit, and a controller that allows a user to position the movable structure on which the sensor is mounted, e.g., a door or window, at a selected position and then arm the security system with the structure in that position to detect movement of the structure away from the selected position. For example, the user may open a window on which the sensor is mounted and then arm the alarm to trigger upon detection of movement of the window from that position or, alternatively, only upon detection of further opening of the window or, alternatively, only upon detection of closing of the window. A user could thus open a window a small, selected amount to admit fresh air without triggering the security system or open a door a small, selected amount to receive a caller or allow pets to enter or leave the premises without triggering the security system.

Abstract: A traffic sensor for dispostion across a lane or lanes of a roadway includes a pliable strip within which is housed a flexible carrier which in turn supports electrical sensors and coaxial cables. The components are in circuit with a roadside located recording device. Vehicle imparted loads applied to the strip and carrier are counteracted by an inelastic member extending lengthwise of the strip to prevent erroneous electrical impulses. The inelastic is embodied in strands of material embedded in the carrier. Fastener elements extend through the strip for insertion into the roadway for strip retention.

Abstract: A vehicle's position is determined, normally within .+-.0.37 inches, relative to an imaginary center line of a road lane along which are buried, normally about every 13 feet, completely passive resonant circuits, normally each a simple, inexpensive and durable 1-turn 11.5" diameter shallow loop of #12 copper wire in series with a proper capacitor, nominally 10 nanofarads, for resonance. In-lane positional determination is in and by a phase detection circuit, and process. A low-power r.f. electromagnetic field, normally 1.9432 MHz, is maintained in a (i) vertically- or (ii) horizontally-oriented first loop, normally a 6-turn 6-inch coil. Resonance is electromagnetically induced in nearby road coils; radiated fields are not involved. The induced r.f. field is itself then detected in a another, second, loop means within the vehicle.

Abstract: A method and apparatus is provided for determining if a vehicle with an operating engine is at a particular location, the apparatus comprising: an antenna comprising a continuous wire formed into at least one loop; and a means to determine when the antenna is exposed to an oscillating electromagnetic field having a frequency between about 700 and about 2100 Hz of a strength characteristic of a vehicle's alternator operating in the vicinity of the antenna. In a preferred embodiment of the present invention, the sensor of the present invention further comprises a means to generate a signal when the antenna is exposed to the oscillating electromagnetic field having a frequency between about 700 and about 2100 Hz of a strength characteristic of a vehicle's alternator operating in the vicinity of the antenna, and the signal is used as an input into a logic system that requires that the signal not be generated in order for a refuelling system to refuel a vehicle in the vicinity of the antenna.

Abstract: A detection device for data relating to the passage of vehicles over a road. The detection device is to be placed in a groove provided in the upper portion of the road and comprises a first profiled strip provided with an upper cavity in a U-shape, and a piezoelectric cable of the coaxial type arranged in the bottom of the cavity of the first profiled strip. A second profiled strip is arranged in the cavity of the first profiled strip on top of the coaxial cable. The second strip has a shape and dimensions such that it fills up the remaining volume of the cavity above the cable and seals this cavity.

Abstract: A electronic license plate system having an identification device embedded in a license plate portion and electronics stored in a license plate holder ensures that the proper identification device is connected to the electronics. The identification device is constructed in a manner such that tampering with the device will render is inoperable. Also, if an improper license plate is mounted to the license plate holder of a vehicle, a security system will disable the electronics of the system or will transmit a alarm signal.

Abstract: A device and method for passively activating an inductive loop vehicle sensor. The sensor has an inductive loop in a roadway that produces an electro-magnetic field and utilizes the changes caused by the interaction of a detectable vehicle with the field to activate it. The device includes at least one metallic foil having sufficient area and thickness to cause changes sufficiently similar to changes caused by a detectable vehicle to activate the sensor when said foil is placed within the electro-magnetic field. The method includes providing such a device and deploying the device in a plane substantially parallel to the roadway and within the field of the loop.

Abstract: A vital wheel detector for railways injects an oscillating electrical current into a short rail segment and produces a monitor signal in response the magnetic field around the rail. A high Q pickup coil is employed which, when a car wheel is present on the rail segment, sharply decreases in Q and significantly reduces the level of the monitor signal. Any failure of the detector apparatus is in a safe mode, as a loss of rail current results in a loss of the monitor signal whether through an electrical or a mechanical failure. Also, internal mechanical or electrical failures either interrupt the current to the rail or interrupt transmission of the monitor signal to the processing logic.

Abstract: The invention relates to a method and a device for determining the speed s/.delta.t) of vehicles, in which with the aid of at least two sensors (1, 2, 27, 28) spaced apart from one another (distance s), the time .delta.t=t.sub.1 -t.sub.2 required to drive over both sensors (1, 2, 27, 28) is ascertained. The object of the invention is to disclose a speed measuring method that is simple to accomplish, with which accurate measurement values are ascertainable, and in which external factors of the pavement can largely be ignored. This is attained essentially by using induction loops, instead of the usual piezoresistive pressure sensors, as the measurement sensors (1, 2, 27, 28).

Abstract: A method of obtaining data relating to the performance of an inductive loop detector wherein a light source is modulated with a signal which is dependent on the data and the modulated signal is remotely detected and data extracted therefrom is stored for later processing.

Abstract: A device for detecting one or several wheels of a vehicle or of a wheeled engine and a process using this device. The device is constituted by at least one electromagnetic loop and by an evaluation unit. The electromagnetic loop or loops have a small dimension in the direction of the displacement of the vehicle or of the axis of the roadway, which is less than the diameter of the wheels of the vehicles to be identified, and a rectangular shape and/or a rectilinear arrangement disposed perpendicularly to the axis of the roadway, the loop or loops being sensitive in a distinct and opposed manner to the electromagnetic influences of the metallic masses moving in translation and in rotation, at the wheels of the vehicle.

Abstract: An electronic license plate architecture is described wherein a license plate portion has a conventional license plate having visual information thereon and an identification device integrated therewith. The identification device stores restricted information. A license plate holder supports the license plate portion and houses communications and signal processing electronics. An antenna may be integrated with the license plate portion or may be housed in the license plate holder.

Abstract: A train detection device for use in railroad models is provided with a capacitance type sensor which detects the close approach or passage of a train by responding to capacitance of the train. By using the capacitance type sensor, the train detection device becomes a non-contact type detection device, which avoids the kind of damage that can occur with contact type detectors. The train detection device is applied to a train crossing control apparatus for use in railroad models equipped with a crossing gate, a warning signal, and a controlling device for controlling the operations of the crossing gate and the warning signal.

Abstract: An initialization beacon for initializing a stationary vehicle, particularly for assisting the driving, operation, and maintenance of the stationary vehicle, comprises superposing cross-over structures Si, whereby each cross-over structure is made from a first electrical cable Ci1 and a second electrical cable Ci2. The first electrical cable Ci1, which mutually parallels with the second electrical cable over most of its length, crosses over the second electrical cable Ci2 to form a succession of magnetic nodes N. The magnetic nodes of each of the superposed cross-over structure form magnetic nodes Nij in the superposed cross-over structures. The magnetic nodes NiJ are staggered in a non-overlapping fashion according to a space period in each of the superposed cross-over structures. Pairs Pmn of the superposed cross-over structure Si can be successively powered at a clock frequency FH and a data frequency FD.

Abstract: A detector system filters the effects of periodic noise such as magnetic flux from nearby power lines or other periodic sources. The detector system further adapts in the case that the system incorporates microloops for the inductive sensors. The detector system further counts multiple vehicles while in presence mode. The detector system also logging of vehicle data and system faults.

Abstract: A method and apparatus for detecting objects disposed in close proximity to a conductive loop, includes the use of a sensitivity selection circuit to compensate for loop sensitivity to metal and other conditions, and a microprocessor circuit for helping to prevent false detections or undesired interruptions of valid detection due to changes in environmental conditions.

Abstract: A reference value used in a vehicle detector is checked and adjusted. The vehicle detector determines the speed of a vehicle which it has detected and then makes a sample measurement after the vehicle has left the detection area of its inductive sensor. The timing of the measurement is based on the speed of the vehicle. The sample measurement is compared to the reference value, and adjustment of the reference value is made accordingly. In order to identify the cause of changes in the sensor drive oscillator signal frequency, the frequency of the oscillator signal is measured while connected to a dummy sensor not affected by vehicles. The reference value also is adjusted to reflect slow changes (drift) in sensor drive oscillator frequency. To identify changes in sensor drive oscillator frequency caused by mechanical difficulties which require maintenance activity to correct, a rate of frequency change of the sensor drive oscillator signal is determined over the plurality of measurement scanning segments.

Abstract: A system for scanning the interior of a cargo container includes a propagator device for producing a magnetic field at each of (I) positions adjacent a first side of a cargo container and a detector device for detecting magnetic field strength at each of (J) positions adjacent a second side. The (I) positions are spaced apart in a direction generally parallel to a Y axis of a Cartesian coordinate system and components are included for mapping information about magnetic field strength at each of the (J) positions for each of (K) positions of the cargo container as it passes between the propagator and detector devices in a direction generally parallel to an X axis. Spaced apart orthogonal propagator and detector elements may be disposed in vertical columns adjacent the cargo container, and computerized control components may be used to map and process the information and to produce and display an image.

Abstract: In an apparatus for the transfer of information in motor vehicle traffic between a fixed-position transmitter-building element near a roadway and a receiver arranged in a vehicle, the transmitter-building element emits a coded information signal and the receiver of the vehicle driving past the transmitter-building element displays information from the information signal in the vehicle. In order to make shielding measures unnecessary, with an uncomplicated supply of energy to the transmitter-building element and small construction costs therefor, the transmitter-building element (1) is built into roadway pavement (12). The energy necessary for transmitting the information signal is received by the transmitter-building element (1) from the vehicle (13) which is driving above it.

Abstract: A magnetometer vehicle detector for detecting various parameters of traffic on a roadway. A number of sensors, having a compact package, along with connecting cables, may be placed in road way with a small number of standard width sawcuts. Alternatively, sensors may be placed in the roadway within tubes under the external surface of the roadway. The package design of the sensor is such that the sensor can be placed in the sawcut or tube only in a certain way or ways resulting in the most sensitive axis of the sensor being most likely affected by just the traffic or vehicles desired to be detected and measured. The sensor may be a magnetoresistive device having a permalloy magnetic sensing bridge. Multiple sensors may be placed in single or multiple lanes of the roadway for noting the presence of vehicles and measuring traffic parameters such as average speeds, vehicle spacings, and types and numbers of vehicles.

Abstract: Apparatus for determining the position of a mobile vehicle relative to a fixed location marker device which comprises a coil energized to emit a magnetic field composed of lines of magnetic flux extending radially and arcuately from the ends of the coil's longitudinal axis. A sensor unit mounted on the mobile vehicle comprises four identical sensing coils each responsive to the frequency of the magnetic field of the marker device and each having a major axis. These sensor coils are supported in two pairs with the major axes of the sensor coils of each pair disposed on either side of a common central plane and extending parallel thereto, this common central plane extending transversely to the longitudinal axis of the marker device coil. Each pair of sensor coils is arranged in an X pattern in which their major axes cross each other medially and perpendicularly to define a center for the coil pair.

Abstract: A linear roadway vehicle sensor for sensing vehicular traffic thereover includes a flexible carrier comprising an elongated flat elastomeric member having upper and lower surfaces and at least one groove in one of the surfaces. An elongated pressure sensor is carried in the one groove and a linear weight is distributed along and secured to the length of said flexible carrier. The weight has a weight per unit length which is sufficient to maintain said sensor on said roadway and substantially immune to lifting from the roadway because of air flow effects and turbulence caused by vehicles.

Abstract: A system for monitoring ferromagnetic materials in proximity to a sensing region, which is particularly applicable to traffic monitoring and controlling. A magnetic probe generates a signal in response to magnetic flux changes caused by a vehicle moving through a sensing area. A processor analyzes the signal to determine the duration of the signal and correlates that duration to a vehicle velocity. A checking system periodically sends a checking signal to the magnetic probe and monitors the return signal to verify that the probe is operative and also analyzes the return signal to determine whether a stationary vehicles is in the sensing area.

Abstract: A linear roadway vehicle sensor for sensing vehicular traffic thereover includes a flexible carrier member comprising an elongated flat elastomeric member having upper and lower surfaces, a recess formed in the lower surface. The recess has a first top surface and a linear weight is distributed along the length of the flexible carrier. An adhesive secures the linear weight in the recess in said flexible carrier. The weight has a second top surface and a weight per unit length which is sufficient to maintain the sensor on said roadway and substantially immune to lifting from the roadway because of air flow effects and turbulence caused by vehicles, and one or more sensor grooves formed in the top surfaces and an elongated sensor in the one or more sensor grooves and between the elastomeric member and the linear weight means.

Abstract: A linear roadway sensor in which a distributed weight member has a weight per unit length which is sufficient to maintain the sensor on the roadway and substantially immune to air effects generated by vehicular traffic on the roadway. A method of safely installing the sensor is to pivot one end at the edge of the roadway and then swing the sensor on an arc then allowing the weight to maintain the sensor on the roadway.

Abstract: A race recording and display system includes a detection station for detecting each participant in a race. The detection station has an array of detection signal transmitting devices and identifying signal receiving devices arranged over a race course in sufficient numbers to irradiate a portion of the course ensuring detection and identification of each participant traversing the station. Detection results from the reflection of a portion of a detection signal transmitted by each transmitting device sufficient to provide an identifying signal unique to each participant to each receiving device. Identifying means carried by each participant provides the identifying signal upon irradiation by a detection signal. Determining means responsive to each identifying signal relates the identifying signal to each participant, fixes a time of receipt of the identifying signal and generates an information signal for transmission to a display means.

Abstract: A usage parameter control circuit for effecting a policing control in an ATM transmission network, comprising a time interval measuring unit for measuring a time interval between a current arrival time of a cell to be judged, and an arrival time of a cell which arrived a reference threshold number of cells before the currently arriving cell arrives; and a judging unit for judging whether or not the measured time interval is shorter than a reference threshold time interval, whereby a longer accessing time is allowed and the circuit construction has a flexible expandability.

Abstract: Charging apparatus for use in a road vehicle enables an authority to charge for road usage. As the vehicle is used on controlled parts of road way, debiting means debits credit units at a predetermined rate. A store keeps a record of the credit units used. The debiting rate can be preselected. An alphanumeric display can be visible through the windscreen of the vehicle to enforcement officers as the vehicle passes. The display can show the debiting rate currently in use. A pre-payment credit card system may be employed to charge the apparatus with credits. An internal display for the driver allows the driver to select the debiting rate demanded by signs along the controlled roadway.

Abstract: An object detecting device for detecting an object at least partly having a magnetic substance or magnetic-flux permeable material is formed of a detection coil arrangement including a primary coil for generating magnetic flux and a secondary coil disposed separately from the primary coil at a predetermined interval for receiving the magnetic flux from the primary coil; and a detection circuit for detecting an increase of the magnetic flux transmitted to the secondary coil due to presence of the object within a space between the primary and secondary coils. The detection circuit produces signal indicating the presence of the object upon detection of the presence.

Abstract: A sensor for detecting a magnetically permeable mass by the disturbance of the earth's magnetic field in the vicinity of the sensor comprises a ferromagnetic strip with a conductive winding wrapped thereabout, a means for magnetically biasing the strip such that regardless of orientation the earth's magnetic field and the strip placing the ferromagnetic strip in a position on its BH curve where the slope is substantially linear, a means for generating an analog signal indicative of the inductance of the winding as the earth's magnetic field is disturbed in the vicinity of the ferromagnetic strip causing a change in the inductance of the winding, a means for digitizing the analog signal at spaced time intervals to produce a series of digitized values, and a digital computer means for processing the digitized signal values to characterize the presence and/or motion of the permeable mass.

Abstract: Traffic monitoring equipment including traffic speed measuring equipment has a signal validation facility incorporated to enhance reliability of the equipment. This facility permits the monitoring operation, for example speed measurement, to proceed only if the validation is positive, if negative the operation is aborted and/or a warning signal or shutdown is activated. Validation is made of pulse sequence, pulse strength, radio frequency interference, insulation breakdown, cable integrity (where cables are used) and the like.

Abstract: A vehicle detector includes an inductive sensor which is driven by an oscillator to produce an oscillator signal having a frequency which is a function of inductance of the inductive sensor. Presence of a vehicle is detected when measured frequency of the oscillator signal changes by more than a threshold value. The effects of magnetic flux produced by adjacent power lines are compensated by measuring the frequency of the oscillator signal during a plurality of sample periods and characterizing the fluctuation of the measured frequency as a function of phase of a power main signal. During a normal measurement period, the frequency of the oscillator signal is measured, and the phase of the power main signal during the measurement period is determined. An output signal is produced based upon the measured frequency, the phase, and the known fluctuation of measured frequency as a function of phase of the power main signal.

Abstract: An oscillator which produces a continuous wave output signal on an antenna having a preset frequency. A detection circuit detects changes in the preset frequency resulting from proximity between the antenna and an object and when such an object is detected, the detection circuit generates an output signal. A compensation circuit is also provided for compensating for changes of the preset frequency which are caused by factors other than proximity of the antenna with an object. Such other factors include radio frequency interference, long term component degradation, temperature, and the like.

Abstract: A passive velocity measuring system which includes first and second biaxial fluxgate magnetometers separated by a known distance and oriented precisely with respect to one another and with respect to the path of travel of a ferrous vehicle whose velocity is to be determined. An indication of the velocity of the vehicle is obtained from the ratio of the time derivative of the magnitude of the vehicle's magnetic induction to the negative of the spatial derivative of this same quantity.

Abstract: A vehicle detector includes one or more inductive sensors connected to an oscillator circuit. A timing circuit defines a plurality of sequential measurement frame segments. The oscillator circuit is coupled to an inductive sensor during each of the measurement frame segments. The time duration of each of the plurality of measurement frame segments is measured. After the completion of each frame segment for a particular inductive sensor, a total measurement frame time duration for that sensor is calculated based upon durations of a predetermined number of measurement frame segments for that sensor. The total measurement frame time duration and a reference time duration are compared and a difference is determined. If the difference between the total measurement frame time duration and the reference time duration exceeds a threshold value, an output signal indicative of the presence of a vehicle in the vicinity of the inductive sensor is generated.

Abstract: A determination is made whether a minimum threshold period (or frequency) change has occurred in an oscillator signal indicating the initial presence of a vehicle over an inductive sensor. The change in period of the oscillator signal is measured over each of a plurality of frame segments. A magnitude of period change in the oscillator signal is recorded. If the number of frame segments that occur between detection of the threshold change in period and the magnitude change in period is less than a predetermined number, the detector does not make a speed measurement calculation. If the number of frame segments equals or exceeds the predetermined number, the time rate of change of the period of the oscillator signal is estimated. A vehicle detector calculates a sensor entry distance for a particular vehicle. A vehicle entry time is calculated by dividing the magnitude of period change by the rate of period change. Speed is then calculated by dividing the entry distance by the vehicle entry time.

Abstract: An estimate of the number of vehicles crossing a loop inductor having one or more interconnected discrete loops of the type found in vehicle detector system installations. A measuring signal follows changes in loop inductance caused by the influence of vehicles crossing the loop inductor. A vehicle count threshold value is computed by observing changes in the measuring signal caused by the first car crossing the loop. Subsequent excursions of the measuring signal between relative minima and relative maxima are tested against the threshold and a vehicle count event is registered when the differences exceed the threshold. After a predetermined count period, the number of vehicle counts is estimated from the total count events by multiplying them by an interpolation factor determined empirically from the type of loop inductor. Apparatus for perfoming the method is combined with a conventional vehicle detector system in a switch selectable apparatus for specifying vehicle detector mode or vehicle count mode.

Abstract: The system comprises transceivers employing identical modems, one located at a fixed position and connected to the wire and one on a vehicle guided along the wire. The transceiver's specialized modems may be connected to a central host which may be a computer, to a programmable controller, or to a communications bus as required. Additional transceivers may be connected to the communications bus for communication between the central host and additional wires. All central host signals are transmitted to all wire connected modems and sent out on all wires. All signals from vehicle modems are transmitted back to the central host. Each transceiver is adapted to employ one or more identical modem, each connected to a different wire.

Abstract: A device for detecting data relating to the passage of vehicles on the road including a piezoelectric effect cable and a cylindrical metal tube having an inside diameter which is larger than the outside diameter of the piezoelectric cable with the space between the cable and inner walls of the tube being filled with a compacted metal oxide power.

Abstract: A system for collecting a toll for a vehicle, on which a vehicle number plate is mounted, is disclosed. In the system, a radio card as a storage medium is provided in the vehicle. The radio card generates a data signal representing a identification data including a vehicle number data. A radio card access system receives the data signal transmitted from the radio card and processes the data signal to obtain the vehicle number data contained in the radio card. A TV camera picks up an image corresponding to a vehicle number from the number plate of the vehicle. The radio card access system generates vehicle number plate data from the image picked up by the TV camera. The radio card access system compares the vehicle number data and vehicle number plate data and verifies whether or not the two sets of data coincide, the toll of the vehicle is calculated in accordance with the identification data stored in the storage medium.

Abstract: A method and system for transferring information between a moving vehicle and a stationary information location having a vehicle detector system with a loop antenna by using the loop antenna as either the receiving antenna for signals transmitted from a moving vehicle or as the transmitting antenna for signals generated by a transmitter located at the vehicle detector site for transfer to a receiver mounted on a moving vehicle. The information is encoded on a carrier having a frequency outside the normal frequency range of the vehicle detector system, preferably by interrupted carrier pattern processing.