Abstract: An integrated multiple-function communication system for highway, railroads and other applications, the system comprising a wideband coaxial trunk cable with associated amplifier/repeaters for long-distance point-to-point transmission of a plurality of carrier signals combined with inductive-signaling means including frequency-converter/amplifiers each having an input physically coupled to the coaxial trunk cable and an output coupled to an inductive-signaling conductor, the latter disposed within the trunk-cable structure or electrically related thereto whereby a relatively-uniform electromagnetic field of a desired strength is established along a highway or other service zone for inductive-carrier communication with vehicles, roadside call boxes and other devices located in proximity to the cable which interconnects with a control or terminal point.

Abstract: A communication system for the transmission of the sound portion of motion pictures or the like in drive-in theaters directly to automobile radios by means of an induction cable buried beneath the ground in the reception area in which automobiles viewing the motion picture are to be parked. The cable is of such design that when properly positioned and combined with an amplitude-modulated radio frequency signaling means, a relatively uniform amplitude-modulated electromatic field of the desired strength and of a frequency which is within the normal reception range of car radios (i.e. the standard broadcast band) is established throughout only the area where the automobiles are parked.To limit signal reception outside the designated parking area of a drive-in theater an interfering signal is transmitted by coupling audio-modulated radio-frequency energy to nearby electric power lines of overhead type or by means of a transmission line or cable adjacent and outside the theater area.

Abstract: A radio-frequency signaling cable comprising a center conductor, dielectric means disposed about the center conductor, and a conductive sheath disposed about the conductor and dielectric means. An inductive signaling conductor is spaced-apart from the sheath by second dielectric means in a fixed spaced position to establish a predetermined characteristic impedance of an inductive signaling transmission line which is formed by the inductive-signaling conductor and the sheath. An insulating jacket encapsulates all of the conductors and dielectric means.