Radio Broadcasting Systems: Digital Audio Broadcasting (DAB+) to mobile, portable and fixed receivers Author: Eng. Iván Rodríguez Portas 16/09/2015 Mail: ivan@lacetel.cu
GOAL Presentation of a technical overview and main features of the DAB standards family Mail: ivan@lacetel.cu 01/17
OUTLINE DAB+ features. Technical Specifications. Conceptual Block Diagram. Transmission Frame. DAB+ service Structure. Conclusions Mail: ivan@lacetel.cu 02/17
DAB STANDARDS FAMILY DAB: 1995 Original audio with PAD and data services standard. DAB+: 2007 Enhanced audio service efficiency. ETSI Standard Documents EN 300 401 Main Document TR 101 496-1, -2, -3 Guidelines of use and operation TS 102 563 Transport of AAC audio Mail: ivan@lacetel.cu 03/17
DAB/DAB+ COVERAGE Source: https://www.worlddab.org/country-information Mail: ivan@lacetel.cu 04/17
DAB+ FEATURES (1 of 5) Audio Coding Quality. DAB+ uses MPEG-4 High Efficiency AAC v2 profile (HE-AAC v2) audio codec. A 48 kbps subchannel with HE-AAC v2 provides a similar audio quality as MPEG Audio Layer II at 128 kbps. Up to 18 programs at 64 kpbs in one ensemble. Mail: ivan@lacetel.cu 05/17
DAB+ FEATURES (2 of 5) Choose the station from a list. Station List Easy to choose a station, listener has more information about the services availables Mail: ivan@lacetel.cu 06/17
DAB+ FEATURES (3 of 5) Program Associated Data (PAD): Dynamic Label Segment Text Delivery. Up to 128 characters per text segment. All DAB+ receivers have DLS text display. Mail: ivan@lacetel.cu 07/17
DAB+ FEATURES (4 of 5) Program Associated Data (PAD): Slideshow (SLS) Images. The audio message can be strengthen. Traffic and weather reports. Sport results. Local news, happenings, community events. Mail: ivan@lacetel.cu 08/17
DAB+ FEATURES (5 of 5) Data Services: Electronic Program Guide (EPG). Is flexible, can be station, network or ensemble based. Some receivers can record programs for later listening. Mail: ivan@lacetel.cu 09/17
CONCEPTUAL DAB+ EMISSION BLOCK DIAGRAM Services Configuration MUX controller FIC generator Control Programme Associated Data PCM Audio Signal Data Services Audio Encoder Data Encoder DAB Audio Frame Channel Encoder Energy Dispersal Channel Encoder Energy Dispersal Convolutional encoder Convolutional encoder Time Interleaver Time Interleaver Main Service Mux Mail: ivan@lacetel.cu 10/17
CONCEPTUAL DAB EMISSION BLOCK DIAGRAM Fast Information Channel Main Service Channel Trasnmission Frame Multiplexer Synch. Channel symbol gen. FIC and MSC symbol gen. OFDM signal gen. DAB transmission signal Mail: ivan@lacetel.cu 11/17
TRANSMISSION FRAME The duration of the transmission frame depends of the transmission mode Transmission Frame Synchronization Channel non time-interleaved Fast Information Channel (FIC) time-interleaved Main Service Channel (MSC) FIB Fast Information Block FIB CIF CIF Common Interleaved Frame Mail: ivan@lacetel.cu 12/17
TRANSMISSION MODES (1 of 2) Transmission mode I: intended for SFN in Bands I, II and III Transmission mode II: intended for local services in Bands I, II, III, IV, V and L-band Transmission mode III: intended for frequencies below 3 GHz and cable Transmission mode IV: intended for local services in Bands I, II, III, IV, V and L-band (for optimum SFN operation in L-band) Mail: ivan@lacetel.cu 13/17
TRANSMISSION MODES (2 of 2) Transmission parameters that changes between transmission modes: Number of carriers on the OFDM modulation. Carriers spacing. Symbol duration. Symbol guard interval. Mail: ivan@lacetel.cu 14/17
DAB+ SERVICE STRUCTURE Ensemble DAB ENSEMBLE ONE Services ALPHA 1 RADIO BETA RADIO ALPHA 2 RADIO Service components MCI SI Data Audio Audio Data Audio Service FIDC Fast Information Channel SubCh a SubCh b Mail: ivan@lacetel.cu 15/17 SubCh c SubCh d Main Service Channel
CONCLUSIONS DAB+ provides a variety of interesting features. This features may help to improve the audience of the radio broadcast service in our country. The DAB service multiplex is sufficiently flexible to provide a wide choice of service arrangements to suit programming needs. Mail: ivan@lacetel.cu 16/17
BIBLIOGRAPHY 1. ETSI EN 300 401 V1.4.1 (2006-01). European Standard (Telecommunications series) Radio Broadcasting Systems: Digital Audio Broadcasting (DAB) to mobile, portable and fixed receivers. 2. ETSI EN 300 563 V1.2.1 (2010-05). Digital Audio Broadcasting (DAB); Transport of Advanced Audio Coding (AAC) audio. 3. EBU Technical Review Spring 1994. The DAB multiplex and system support features. J.L. Riley. 4. 2011 Broadcast Fair Presentation. El Nuevo plan de digitalización de la radiodifusión sonora terrestre y el DAB+ en España, Fernando Almaraza Hernán-Pérez. Mail: ivan@lacetel.cu 17/17
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