10 May Every DRM Transmission is Maintained by a Single Broadcaster – Your Question Answered
Our best specialists will respond in brief to your questions. We will post them regularly. Please submit them in writing and in audio with your picture and we will post the answers here. Please keep your questions short and relevant and send them to: projectoffice@drm.
10th May 2021
What is the mechanism for local channel insertion when SFN (single frequency network) is used in the radio network using DRM transmitters? [Mahavir Duhan]
Local channel insertion is not required for DRM, as every DRM transmission is maintained by a single broadcaster. For DAB+ and DVB-T(2) services on the other hand, it would be a nice feature, as those are multiplex approaches where a single broadcaster is NOT in charge of their own signal component. If you need to transmit a different composition of DRM services in different areas, you simply send a separately created MDI signal from the studio to that other region. However, with multiple broadcasters sharing the transmitter infrastructure in band II or III, resulting in multiple DRM signals being broadcast in the spectrum side-by-side ( as recently demonstrated in India), every individual DRM signal can either be transmitted from only some transmitters in the SFN area, or from multiple or all transmitters. This allows for a form of “local channel insertion” solution for shared transmitter setups within SFN areas.