Idaho might as well be in the South , honestly . <| sep |> No . DAB is an alldigital transmission in a different frequency band , but the two places DAB is usually transmitted the LBand or highVHF are already used in the US for other things military telemetry and channels 7 through 13 . HD Radio is sometimes called IBOC because it ' s inband , onchannel . It is transmitted via two digital sidebands that surround the analog FM signal . ~ liueteachingcommstandards 2011 FHDRadioindexfilesimage 009 . jpg There is also a digitalonly mode , but nobody ' s using it because then there ' d be no analog FM signal . Canada and Mexico both tried DAB . In Canada , it got deployed in a few cities but nobody was listening , so HD Radio wound up being approved for use there . In Mexico , broadcasters in northern Mexico got alarmed by the potential of losing their US audience when it was tested in the 90 s . Instead , Mexico approved HD Radio for stations within 320 kilometers of the US in 2008 , and for stations in all areas in 2011 .