RadioEPG Service Following details for DAB

[Ben Poor]

Dear RadioDNS Team - for those of you not on the RadioEPG list and interested in implementations of Service Following, the following post was made regarding implementations of service following to DAB devices, particular in-car.

I would strongly recommend getting involved in the discussion on the RadioEPG list if you have any comments or suggestions.

Ben

Dear All, 

During some work on an XSI generator it was commented that it may be useful to include extra information when specifying DAB bearers, in order to assist client implementation of Service Following. The scenario is described as following:
Take a device within a car listening to a service via IP. It has the capability to perform Service Following, by switching between bearers for that Service, enabled using the XSI document from the Service Provider.
In order to determine whether the service is available on DAB, it can use the DAB Bearer details (ECC, EId, SId, SCIdS) but to do this for a device with a single DAB receiver, it needs to constantly scan the DAB spectrum and acquire any ensemble details. This takes a finite amount of time (around 90 seconds, say), which is wasteful and would provide a poor user experience for a device moving between areas of DAB broadcast.
To help with this, an indication of the frequencies on which ensembles exist carrying that service can be included in the XSI against the DAB bearer details, presumably one per DAB Bearer ID for the ensemble that Bearer exists within. This would *narrow* the search for that service when roaming between ensembles, enabling Service Following to happen more smoothly.
For instance, for the DAB bearer definition: 

<serviceID cost="10" id="dab:ce1.c181.c2a1.0" mime="audio/mpeg" offset="2000"/> 

This could include the frequency. I would prefer to have this as part of a possible URI for a DAB Bearer, although I am open to suggestion to how this could be formatted. The frequency will need to remain optional, and should co-exist with the other optional part of the URI (SCIds/X-Padd AppType). One possible format is: 

<serviceID cost="10" id="dab:ce1.c181.c2a1.0/223946" mime="audio/mpeg" offset="2000"/> 

With the Ensemble frequency appended to the bearer URI in KHz.
Thats off the top of my head - open to other suggestions and comments.

 

Thanks,

 

Ben
ben....@radiodns.org