World Broadcasting Unions Digital Radio User Manual - page 28

DIGITAL RADIO GUIDE

TERRESTRIAL TRANSMISSION SYSTEMS - DAB

28

T-DMB receiving devices have become available and  are integrated within mobile

phones, in portable PCs and small screen portable devices. Several pilot trials and 

projects are ongoing in Korea, UK, Germany, France and elsewhere. It should be

noted that Korea has deployed both Satellite (S-) and Terrestrial (T-) DMB,

although these have limited technical similarities leading to very different terminal

devices. T-DMB was introduced in Korea in mid-2005 using an existing terrestrial

network in Band III (although formal commercial launch has been delayed whilst

business issues are coordinated).  Frequencies in L-Band are available in much of 

Europe for possible use with DMB and DAB.

European T-DMB was officially launched on 7 June 2006 in Munich on the

occasion of the World Football Cup. The launch was organized by WorldDAB and

its partners.

(a)

IP over Enhanced Packet Mode

Enhanced Packet Mode (EPM) provides additional error protection for DAB

packet mode-based services, such as IP and MOT (Multimedia Object

Transfer), by the use of a DAB-FEC frame and the addition of FEC packets

(in a similar way to the DVB-H MPE-FEC). The same Reed-Solomon code is 

used as in DMB.  Interleaving is different from T-DMB and allows backwards-

compatible reception of EPM services on receivers with conventional DAB

packet mode. The EPM specification has been submitted to ETSI.

(b)

DAB-IP

The BT Movio's "DAB-IP" system is a DAB application of IP over Enhanced

Packet Mode. Technical trials in UK by British Telecom started mid-2005 and 

ran through to the end of December 2005. Microsoft’s solution for video and

audio coding as well as digital rights management (DRM) have been

selected for this pilot. The electronic programme guide (EPG) designed for

BT Movio and standardized by ETSI proved quite successful. DAB-IP

enables DAB digital radio to share multiplex capacity with mobile TV and

therefore allows TV operators to benefit from the considerable DAB spectrum 

and infrastructure investments that have been made across Europe. The

prototype DAB-IP devices were based on a fully functioning 2.5G mobile

phone which included an integrated DMB receiver, so that users could enjoy

broadcast digital TV and radio services using advanced EPG.

(c)

The German DXB Project

Digital Extended Broadcasting (DXB) is a German-funded project running

until 2007. The DXB concept will offer similar services to DVB-H over a DAB-

based transmission system. Services may use the IP-protocol over

Enhanced Stream Mode (using MPEG-2 TS as with DMB) or via the

Enhanced Packet Mode.

It should be observed that an alternative broadcast system for mobile

multimedia applications is being developed in the framework of the DVB

Project: DVB-H (H stands for handheld). Some EBU research institutes are in 

the process of looking into the technical and operational merits of DVB-H and