New HF/MF Digital Maritime Mobile Systems Globe WirelessGlobe Wireless?Global provider of munications Solutions?Managing customer email & data services for 15 years?Installed on more than 4000 ships?Basis of meeting regulatory driven applications–GlobeAlert ship security alert system–GlobeLocator long range identification and tracking of ships–GlobeWeather forecasts–Other fleet management functionsConnected WorldwideThe Maritime work?“Always on” connection?25 HF stations world wide?Approximately 300 channel pairs?Half receive and half transmit?Delivers 50,000 messages per day?Alternative to satellite systems?Traffic doubles every 18 months–Message growth and new applications–Flexible for efficiency improvementGlobe Wireless ReliabilityGlobe Wireless Reliability?Guaranteed message delivery?Multiple frequencies and work operating centers in California and England?All stations have backup power?% service availability over the last four years?Ships use both HF and munications?Shipboard equipment is self diagnosing?24/7 customer supportBelow Deck Equipment?puter?Marine HF radio?Globe Wireless modem?Power supplyAbove Deck Equipment?Vertical antenna?Antenna coupler?GPS receiverGlobe Wireless Modem?Small form factor?Uses digital signal processing technology?Call set up protocol is a simple extension to NBDP?Bandwidth efficiency of about two BPS per Hertz?OFDM modulation rather than single carrier–Resistant to multipath fadingNBDPGlobe Wireless500 Hz, 1 Tone???3000 Hz, 32 TonesOFDM Spectrum0500100015002000250030003500400045005000-50-45-40-35-30-25-20-15-10- kHz Wideband Signal SpectrumFrequency (Hz)Magnitude(dB)
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