HDRADIO
HD Radio
HD Radio is the trademark for iBiquity's in-band on-channel digital radio technology used by AM and FM radio stations to transmit audio and data by using a digital signal embedded “on-frequency” immediately above and below a station's standard analog signal, providing the means to listen to the same program in either HD or as a standard broadcast . The HD format also provides the means for a single radio station to simultaneously broadcast one or more different programs in addition to the program being transmitted on the radio station's analog channel. It was selected by the United States Federal Communications Commission in 2002 as a digital audio broadcasting ...The above text is a snippet from Wikipedia: HD Radio
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