How does HD Radio work on FM?
On the wider sidebands of FM stations, HD Radio can carry multiple streams of FM and/or AM quality. National Public Radio in particular hopes to be able to carry several different streams through the transmitters of member stations, calling its proposed addition to the FM standard “Tomorrow Radio”. Some have also proposed using the system to carry surround sound broadcasts with 5.1 channel audio, though this or other multichannel setups reportedly may prevent the fade-to-analog fallback on “hybrid” analog+digital broadcasts. Also, the FCC is still only authorizing multichannel use experimentally to individual stations who ask permission. However it seems to be becoming a de facto standard now that so many stations have adopted it. Currently, FM stations in the United States and Canada are licensed to occupy approximately 200 kHz of RF spectrum, i.e., the FM band frequency allocations are 200 kHz apart. When a signal modulates the carrier, an infinite number of harmonically-related side
Related Questions
- Will FM SCAs (67 & 91 kHz) be protected with the addition of the HD Radio carrier? Will it be possible to continue the SCA signal when the analog carrier is eliminated?
- About a third of my (FM) station`s listenership is via an on-channel Booster station. What are the HD Radio issues with synchronous on-channel Boosters?
- Does HD radio transmit from the same transmitter as analog FM?
