Accession Number : ADA191769

Title :   A Statistical Description of Shipboard Environment and Emitter Signals within a 250 MHz Band at 1 GHz.

Descriptive Note : Professional paper for period ending Jun 87,

Corporate Author : NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA

Personal Author(s) : Cronyn, W R

PDF Url : ADA191769

Report Date : Dec 1987

Pagination or Media Count : 3

Abstract : Measurements are being taken to achieve and ensure Electromagnetic Compatibility between the shipboard Joint Tactical Information Distribution System, scheduled for introduction into the U.S. Navy in the 1990's, and existing shipboard radar, beacon and identification systems. The description of the electromagnetic environment in time and frequency is complicated by the inherent structure of the emitted signals because they are pulsed, some at irregular pulse periods, and radiated from rotating antennas. The signal level distribution is further complicated by reflections off other rotating antennas. The complex time/frequency structure of the signals and the statistical nature of the JTIDS system suggested that the signal level measurements should be statistical. The shipboard system used for the measurements presented in this paper is configured around a Hewlett-Packard 8566B spectrum analyzer/85685A preselector operating at a 3 MHz bandwidth, which is comparable to the RF bandwidth of the JTIDS signal. The transducer is a circular array of eight vertical dipoles which can be wrapped around a ship's mast. The instruments are HP-IB controlled with an HP9816 computer which also does real-time processing and transfers data to an HP9133H hard/floppy disc drive. A logging record is maintained on an HP ThinkJet printer with both alphanumeric and graphical data displayed.

Descriptors :   *ELECTROMAGNETIC COMPATIBILITY, *ELECTROMAGNETIC ENVIRONMENTS, *EMITTERS, *RADAR, ALPHANUMERIC DATA, ARRAYS, BANDWIDTH, CIRCULAR, DIPOLES, DISKS, DISTRIBUTION, DRIVES, FREQUENCY, GRAPHICS, IDENTIFICATION SYSTEMS, MASTS, MEASUREMENT, PRINTING EQUIPMENT, PROCESSING, PULSES, RADIOFREQUENCY, REAL TIME, ROTATING ANTENNAS, SHIPBOARD, SHIPS, SIGNALS, STATISTICS, TIME, TRANSDUCERS, VERTICAL ORIENTATION

Subject Categories : Radiofrequency Wave Propagation
      Active & Passive Radar Detection & Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE