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- Equipment, tools, and parts:
- Wireless node communications systems
- Document types:
- Contract reports
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Results 1 - 9 of 9
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12/1/1980 - Contract reports, Open File ReportsThe objective of this program was to design and build a self-contained system for remote monitoring of the atmosphere in mines. The system developed uses the mine pager phone line as the primary communication channel and also has the capability of using...
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9/1/1980 - Contract reportsThis report adds to the current body of underground communications system design knowledge by: accurately defining (measuring) the 12 dB SINAD sensitivity of the system receivers and then stating the equivalent magnetic field strength in uA/m; showing t...
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7/1/1979 - Contract reports, Open File ReportsThis report describes a complete system design for medium frequency ( MF) wireless radio systems for use in coal mines. The emphasis is on AC mines where no trolley wire exists and, for which, conventional trolley phone communications cannot be used. Th...
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10/1/1978 - Contract reportsThis document describes the decision factors that bear on the selection of the modulation process for the wireless underground medium frequency (MF) communication system.
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9/1/1978 - Contract reportsThis report covers antenna design, analysis, and development work suited for use with a wireless radio communication system operating at medium frequency. The work includes the test and evaluation of prototype vehicular antennas developed during the pro...
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9/1/1977 - Contract reportsAn investigation was made of the feasibility of developing compact transmit antennas and/or other means to efficiently couple VLF to MF band radio energy between portable wireless communication units in coal mines. The completely wireless communication ...
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9/1/1977 - Contract reportsThis report describes magnetic field measurements in the Helvetia Coal Co. Lucene No. 8 Mine for purposes of deriving a mapping of the magnetic field strength covering the major haulageways which contain conductors.
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7/1/1975 - Contract reportsThe applicability of voice bandwidth compression techniques to mine wireless communication systems is examined. Promise has been attached to such techniques because the lessened bandwidth gave hope for lessened received noise and hence increased operati...
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12/1/1973 - Conference proceedings, Contract reportsA need arose to assemble individuals who have been active in current research on the topic of electromagnetic communications systems so that the problem of how information may be conveyed by electromagnetic waves propagating through rock media without t...
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Content source: National Institute for Occupational Safety and Health, Mining Program