Radiating coaxial cable with improved water-blocking characteristics

• Main Authors: NUDD, HUGH R, RAMPALLI, SITARAM
• Format: Patent
• Language: English; French; German
• Published: 22.05.1991
• Subjects: ANTENNAS, i.e. RADIO AERIALS; BASIC ELECTRIC ELEMENTS; CABLES; CONDUCTORS; ELECTRICITY; INSULATORS; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING ORDIELECTRIC PROPERTIES; WAVEGUIDES

A radiating cable of the foam dielectric type is provided with improved water-blocking characteristics by provision of a barrier tape between an apertured, corrugated outer conductor and the external jacket surrounding the conductor. The barrier tape is wrapped around the outer conductor is such a away as to completely cover the radiating apertures disposed thereupon. The barrier tape is composed of a hygroscopic material which is highly water absorbent and swells up in contact with any water penetrating the cable so as to form a barrier around the aperture conductor, thereby preventing ingress of water into the apertures of the conductor. The barrier tape is particularly effective in restricting longitudinal migration of water by retaining water that contacts the tape in a high localized fashion. The improved radiating cable construction is particularly adapted to be used in conjunction with a layer of fire-retardant tape disposed over the water-blocking tape to realize a cable which is highly resistant to both water and fire and yet is economical and easy to manufacture and use.