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: 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.

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.

Abstract: A method of updating the reference count in a period shift measurement vehicle detector permits conditional reference count updating in the No Call direction whenever the sample count minus reference count difference value lies between the upper limit of a jitter/vibration guard and band and a positive freeze reference threshold. Decrementing of the reference count is permitted in the call direction whenever the sample count minus reference count lies in a range from 0 to a negative freeze reference threshold. Variable hysteresis for call/no call signal generation is provided in a single vehicle detector, with the call direction threshold selectable between two values.

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.

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.

Abstract: The pedestrian traffic control system of this invention utilizes an endless belt to successively display visible painted WALK, DONT START, and DONT WALK signs in a window of a display unit. The control unit may be employed with an ordinary three-state power system of the type that now operates flashing neon signs, but has the advantage that electric power operates the signs only when a sign is being moved into display position. Three distinct WALK, DONT START, and DONT WALK signs are used thereby avoiding the ambiguity of present systems in which a flashing DONT WALK sign cautions the pedestrian not to start, but to continue on his way. The movement of the endless belt is controlled by detecting markers, such as perforations, on the endless belt, thus assuring proper registration of the signs in display position. Electrical energy that becomes stored while the sign is energized drives the sign to display the DONT WALK sign, if the power fails.