radio window

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British Dictionary definitions for radio window

radio window

noun
  1. a gap in ionospheric reflection that allows radio waves, with frequencies in the range 10 000 to 40 000 megahertz, to pass from or into space
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012