Abstract: A method and apparatus is disclosed for making a sliced phased array transducer formed from a single piezoelectric disk which has been bonded to a metal coated support surface. After bonding, the disk and attached metallic coating are cut into a plurality of conductively isolated staves which are then wired into a sequence which allows the array to emit two beams in opposite directions at a depression angle of about 60 degrees. In use, two of the arrays are used adjacent to each other with one emitting beams along the port and starboard sides of the vessel and the other being rotated 90 degrees to emit beams to the force and aft of the vessel, the four beams thereby forming a Janus configuration. Alternatively, the beams could be rotated 45 so that two beams are directed to both the port and starboard sides.

Abstract: A broad band impedance matching system and method for use with low-profile antennas. The system comprises an antenna formed by a pair of radiating elements positioned on or in proximity to the earth's surface. The antenna has an effective electrical length equal to one half wavelength in a given medium at the lowest frequency in a desired operating range of electromagnetic signal frequencies. Each antenna is preferably electrically insulated throughout its length. Each radiating element of the antenna system is connected to a transmission line so as to match the average magnitude of the impedance of the antenna over the desired operating range of electromagnetic signal frequencies to the impedance of the transmission line. Broad band antenna system performance may be further enhanced by configuring each radiating element such that it has two conductive arms which are joined at one end so as to be parallel or so as to form an acute angle of approximately ten degrees or less.

Abstract: A novel broadband antenna system which is both portable and easily deployed. The system comprises a power splitter, one or more element feed units, and one or more conductive antenna cables, each cable being wound around a reel.Each reel is releasably secured on an end of an element feed unit. Each element feed unit comprises an impedance matching network, and the element feed units also include a novel clip. The clip functions both to releasably retain a reel on an end of the element feed unit during transportation and storage and to electrically and mechanically connect a conductive antenna cable to the element feed unit when the antenna system is being used.In use, the element feed units are connected to the power splitter, and the power splitter is connected to a transmitter/receiver device. One or more conductive antenna cables are then connected to the element feed units using the novel clips.