Introduction of digital radio broadcasting
When introducing digital radio broadcasting in Europe, one may choose between two or three different or
complementary systems. DAB+ is by means of its large-scale architecture suitable for large broadcasters who
wish to broadcast nationwide, such as Swedish Radio (SR) and the nationwide commercial radio broadcasters in
the VHF band III. The same goes for DVB-T2-Lite, a newly developed, modern and efficient standard for
the distribution of mobile digital radio and TV. For smaller broadcasters, such as local commercial radio and
community radio stations that want to maintain their independence, a traditional small-scale architecture can be
built using DRM+ in the VHF band II (FM-band).
In a transition period towards digital broadcasting, SR and commercial broadcasters may continue to broadcast
analog in the FM band and simultaneously broadcast digitally in the VHF band III. Smaller broadcasters such as
local commercial radio and community radio stations can broadcast analog in the FM band and gradually move
to digital on the FM band. A "graceful" transition from analog to digital radio is made possible by simulcast (at
least in theory). This means that initially, the same program is broadcasted in both analog and digital format
simultaneously. And when the time is right and sufficient number of listeners has acquired digital radios, the
shut-down of the analog transmitters can be initiated in order to proceed to entirely digital broadcasting. [See
For smaller broadcasters who may want to remain in the FM band, the situation is somewhat more
complicated. Simulcast requires that sufficient spectrum is available between existing analog broadcasts in order
to squeeze in digital broadcasts in-between. The spectrum availability in large cities is very limited according to
PTS (The Post and Telecom Authority) and becomes problematic as DRM+, due to a certain redundancy, uses
96 kHz RF bandwidth. [See Transmission modes tag and Test B].
Digital Radio Sweden cannot see that DAB can offer any advantage over DRM or DVB-T2. DRM can offer
equivalent functionality as DAB, however with better utility and higher efficiency (more than a factor two). DRM,
in contrast to DAB and DVB-T2-Lite, covers all existing broadcast frequencies, as well as offering a broadcast
system that covers intercontinental broadcasters, large-scale nationwide broadcasters as well as traditional
small-scale local broadcasters' needs.
When used for digital audio broadcasting, DVB-T2-Lite has - due to its significantly greater efficiency (more than
a factor of two) and appealing multimedia flexibility - the potential to become a serious competitor to DAB+.
Particularly as the infrastructure for DVB-T2 is already in place in Sweden for HD-TV and this standard is
suitable for large-scale digital audio broadcasting along with digital television.
The main objective with DRS test transmissions is to first evaluate DRM+ in the VHF band II (FM band) and
later in the VHF band III.