#26
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As to efficient use of spectrum, COFDM and QAM are identical, **IF**
COFDM uses no guard interval, in which case multipath removal has to be done using the same methods as ATSC. ATSC is less efficient by a bit because of the useless lower sideband (using the same coding for COFDM and QAM as NTSC, of course, which can be done using plain 4-VSB for NTSC and 16QAM for the others including the COFDM carriers.) |
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