What about the DAB+ transmission chain?
A significant difference for the broadcaster is that the DAB+ transmitter is not the only device you need to start broadcasting. Unlike FM, where you have an all-in transmitter, you feed the audio directly.
The DAB+ transmitter is not fed with audio directly. But with an Ensemble Multiplex signal containing all the audio and data necessary to transmit a DAB+ signal. The Ensemble Multiplex, in his turn, receives the individual encoded (AAC) radio channels. Therefore you need different Encoders in addition.
It means that transmitting DAB+ signals will need at least 3 devices.
- A DAB+ (AAC) audio encoder (one per radio station),
- An Ensemble MUX to multiplex the participating radio stations,
- A DAB Transmitter to broadcast the signal.
DAB+ is a distributed system. The 3 devices do not have to be at one location. They can be spread over different locations and communicate with each other over specific transmission links or IP networks.
(More detailed information in the “DAB+ in more detail” tab is under preparation)
Sometimes the “DAB+ audio encoder” and the “DAB+ MUX” can be the same device, often called the “DAB+ headend. “
The “DAB+ headend” is purely software and needs more computer skills than radio technical knowledge. Although to configure “DAB+ audio encoders” and Ensemble Multiplex functions, it is necessary to understand DAB+ principles. It is where localDAB.org comes in to help radio managers and technical staff to exploit the DAB+ system optimally.