FM Broadcast Radio
Bandwidth for Mono FMFrequency Modulation is 19 kHzKiloHertz (kHz) 10^3 Hz, with a stereo stream it raises up to 54 kHzKiloHertz (kHz) 10^3 Hz, if there is RDS the bandwidth is 59 kHzKiloHertz (kHz) 10^3 Hz, and if DARC is present it is 92 kHzKiloHertz (kHz) 10^3 Hz.
There are a number of variations on the subcarriers that are placed on some FMFrequency Modulation Broadcast channels. RDS (RBDS in North America), and DARC are some of the data-based subcarriers used to transmit information alongside the FMFrequency Modulation broadcast. The information includes station name, details of current programming, alerts, traffic information, and more. Broadcasting in stereo FMFrequency Modulation also uses subcarriers for left and right channels.
In addition, in North America, HD Radio by iBiquity (Now part of DTS) in-band on-channel (IBOCIn-Band On-Channel (IBOC) is a hybrid method of transmitting digital radio and analog radio broadcast signals simultaneously on the same frequency.) digital radio technology is broadcast on the outer sidebands of some FMFrequency Modulation radio stations. They have a distinctive look, two plateaus flanking the main FMFrequency Modulation analog signal.
Here is a diagram showing the various subcarriers that exist on North American FMFrequency Modulation Radio Broadcasts:
And this is a MPX extracted sample from a radio station in the United States for comparison:
Here are 5 IQ samples of the MPX Multiplexed FMFrequency Modulation spectrum.
Common – 87.5 to 108 MHzMegaHertz (MHz) 10^6 Hz
OIRT – 65 MHzMegaHertz (MHz) 10^6 Hz to 74 MHzMegaHertz (MHz) 10^6 Hz
Japan – 76 MHzMegaHertz (MHz) 10^6 Hz to 90 MHzMegaHertz (MHz) 10^6 Hz
|Data Subcarriers||Stereo FMFrequency Modulation Pilots|
Can be decoded in most SDR spectrum analyzer clients.
- Wikipedia FM Broadcasting
- FM subcarriers
- United States Federal Communications Commission SCA Subcarriers