5 Transmission mechanisms for broadcasting of multimedia and data applications for mobile reception Several types of transmission mechanisms have been described for this purpose; ISDB-T, ISDB-T multimedia broadcasting, Digital System E, TDMB, DVB-H, DVB-SH, FLO, RAVIS and DVBT2 Lite are possible candidates. There are several methods for so called “encapsulation” using either MPEG-2 TS, IP-Packets, or other generic packet data methodologies. Table 1 lists an overview of currently known broadcasting transmission mechanisms for mobile terminals. The technical characteristics shown are subject to change and are by no means exhaustive; they are provided for comparison only. TABLE 1 Summary of mobile digital broadcasting transport mechanisms Standard or Specification Modulation Transport stream RF channel (MUX) size From technical view point (MHz) Receiver power reduction methodology ISDB-T (Multimedia System C of Recommendation ITU-R BT.1833) QPSK/DQPSK or 16/64-QAM OFDM MPEG-2 TS 1/14 of a) 6 MHz b) 7 MHz c) 8 MHz One-segment reception ISDB-T multimedia broadcasting (Multimedia System F of Recommendation ITU-R BT.1833) QPSK/DQPSK or 16/64-QAM OFDM MPEG-2 TS 1/14 × n of a) 6 MHz b) 7 MHz c) 8 MHz n ≥ 1(1) segment reception Digital System E (Multimedia System E of Recommendation ITU-R BT.1833) QPSK CDM MPEG-2 TS 25 Optimized receptions of CDM codes T-DMB (Multimedia System A of Recommendation ITU-R BT.1833) DQPSK COFDM MPEG-2 TS 1.5 Originally optimized bandwidth TABLE 1 (end) Standard or Specification Modulation Transport stream RF channel (MUX) size From technical view point (MHz) Receiver power reduction methodology AT-DMB (Multimedia System A DQPSK, BPSK over DQPSK, MPEG-2 TS 1.5 Originally optimized bandwidth
TABLE 2A Transmission parameters for multimedia systems (for Multimedia Systems A, B, C, E, F) Parameters Multimedia System “A” Multimedia System “B” Multimedia System “C” Multimedia System “E” Multimedia System “F” References Rec. ITU-R BS.1114 System A and TTAK.KO07.0070/R1 Rec. ITU-R BT.1306 System A ATSC Standard A/153 Rec. ITU-R BT.1306 System C Rec. ITU-R BO.1130 System E and Rec. ITUR BS.1547 System E Rec. ITU-R BT.1306 System C and Rec. ITUR BS.1114 System F 1 Channel bandwidths(1) a) 1.712 MHz 6 MHz 1/14 of a) 6 MHz b) 7 MHz c) 8 MHz 25 MHz 1/14 × n of a) 6 MHz b) 7 MHz c) 8 MHz n ≥ 1 (*1) 2 Used bandwidth a) 1.536 MHz 5.38 MHz Nyquist; 6 MHz total a) 432.5 kHz (Mode 1), 430.5kHz (Mode 2), 429.6 kHz (Mode 3) b) 504.6 kHz (Mode 1), 502.4 kHz (Mode 2), 501.2 kHz (Mode 3) c) 576.7 kHz (Mode 1), 574.1 kHz (Mode 2), 572.8 kHz (Mode 3) 19 MHz (occupied band for typical satellite system) “Subcarrier spacing” (see Item 4) + 1/14 × n × a) 6 MHz b) 7 MHz c) 8 MHz n ≥ 1 (*1) 3 Number of subcarriers or segments 192 384 768 1 536 1 1 At most 64 CDM channels n > = 1 (*1) The number of segments is determined by the available bandwidth TABLE 2A (continued) Parameters Multimedia System “A” Multimedia System “B” Multimedia System “C” Multimedia System “E” Multimedia System “F”
TABLE 5A User requirements of multimedia broadcasting systems for mobile reception by handheld receivers (for Multimedia Systems A, B, C, E, F) User requirements Multimedia System “A” Multimedia System “B” Multimedia System “C” Multimedia System “E” Multimedia System “F” High quality multimedia for handheld receivers a) Media type with quality characteristics – Resolution – Frame rate – Bit rate Video 1: – Normally, QVGA, WDF – Up to 30 fps – Various resolutions and frame rates supported Video 2: – Normally, VGA – Up to 30 fps – Backward compatibility with Video 1 supported “N” services: – Each normally 416 240 – Up to 30P fps – Various frame rates supported Each supplemented by: – SVC for higher spatial resolution (to 832 × 480) and/or higher temporal resolution up to 60P fps Video: – Normally, QVGA (320 × 240) or 320 × 180 size – 1530 fps – Various resolutions and frame rates supported Video: – Normally, QVGA (320 × 240) size – Various resolutions and frame rates supported – Normally QVGA (320 × 240) and 525SD (720 × 480) size – 7.5-30 fps – 64 kbit/s to 10 Mbit/s – Various resolutions and rates supported Audio 1: – Stereo – Up to 128 kbit/s Audio 2: – Surround – Backward compatibility with 1 supported “N” Audios: – Stereo – Up to 288 kbit/s HiQ Audio 2: – Surround enabled Bit rate/service: – Highly variable up to ~7 Mbit/s total Audio: – Stereo Audio: – Stereo Audio: – Stereo and surround Data: – Binary data, text, still images – Subtitling (synchronized hypertext with A/V) – Typical combination of AV is QVGA/VGA at 30 fps with stereo/surround audio Data: – Binary data, text, still images – CEA708 closed captioning OMA RME interactivity OMA SG – Typical AV combination is 416 × 240 × 29.97P with stereo audio Others: – Still images – Text – Closed caption Others: – Still images – Text – (Closed caption) Others: – Binary data, text, still images – Audio/video file distribution
5A (continued) User requirements Multimedia System “A” Multimedia System “B” Multimedia System “C” Multimedia System “E” Multimedia System “F” b) Monomedia coding: – H.264/ MPEG-4 AVC – H.264/ MPEG-4 SVC Video: – H.264/ MPEG-4 AVC – H.264/ MPEG-4 SVC Video: – MPEG-4 AVC/H.264 – MPEG-4 – MPEG-4 AVC/H.264 Video: – MPEG-4 AVC/H.264 – Video – – MPEG-4 ER BSAC – MPEG-4 HE-AAC v2 – MPEG Surround – MPEG-1/MPEG-2 Layer II Audio: – MPEG-4 HE-AAC v2 (SBR, PS) Audio: – AAC (SBR optional) – AIFF-C – Stream and file type playback supported Audio: – AAC (SBR optional) – AIFF-C Audio: – MPEG-2 AAC – MPEG Surround – MPEG-4 – MPEG-4 v2 – Stream and file type playback supported – Data format: – JPEG, PNG, MNG, BMP, etc. – text, etc. Data format: – JPEG, PNG – Optional self-declared MIME formats Still images: – JPEG – GIF images: – JPEG – PNG – MNG Data format: – MP4 file – JPEG, PNG, GIF, MNG, BMP, etc. Flexible configuration of services: – – Ancillary and auxiliary data – Real-time audio and video – Digital radio – Multimedia object file casting via carousel system – Electronic Programme (EPG) – Subtitling (synchronized hypertext with A/V via MPEG-4 BIFS) – Real-time audio and video – Digital radio – Multimedia object file casting via FLUTE – OMA BCAST SG – Any combination of realtime audio, video, and data broadcast is available – Electronic Programme Guide – Appropriate service that fits licensed service area can be offered Two or more CDM channels are combined into one logical channel. This mechanism provides flexible configuration audio, multimedia and data services – Any combination of realtime audio, video, and data broadcast is available – Electronic Programme Guide – Appropriate service that fits licensed service area can be offered
TABLE 5A (continued) User requirements Multimedia System “A” Multimedia System “B” Multimedia System “C” Multimedia System “E” Multimedia System “F” Flexible configuration of services: (cont.) – Any combination of the previous contents in the same multiplex and with TDAB services – T-DMB 5 real-time streaming services (QVGA at 30 fps with 368 kbit/s, and stereo 48 kbit/s) per 1.536 MHz spectrum of DMB ensemble – AT-DMB: T-DMB + additional 2~3 video services or TDMB + 1 VGA realtime video streaming service – broadcast using combination of SFN and MFN – Any combination of the previous contents in the same multiplex – National/local broadcast using service identification Because of the nature of BSS (sound) system, the licensed area is national, however gap fillers can provide local services technically – Subtitling (synchronized hypertext with A/V) – National/local area content with SFN network Conditional access (CA) Supported Standardized service protection supported over IP via OMA DRM 2.0. Applicable Supported Applicable Seamless service access Supported Supported Applicable Applicable Applicable Fast discovery and selection of content and services – T-DMB Electronic Programme supported: Support for fast discovery and selection of services based on various criteria, acquisition information for services access – Direct service signalling for subsecond channel acquisition – OMA SG support for fast selection of services based on various criteria, and details about programmes – Content advisories Electronic Programme Guide support for discovery and selection of services Electronic Programme Guide support for discovery and selection of services based on various criteria, acquisition information for services access and content consumption, purchase information Electronic Programme based on SI/PSI of MPEG2 systems and metadata with XML schema (ITU-T H.750)
5A (continued) User requirements Multimedia System “A” Multimedia System “B” Multimedia System “C” Multimedia System “E” Multimedia System “F” Low power consumption for handheld receivers – Low consumption feature of DAB is applied – Optimized narrow bandwidth allows low system clock frequency and simple FFT calculation. Supports subchannel decoding for selected service – Low power consumption via time slicing Narrow bandwidth enables low system clock frequency The broadcasting system has a mechanism for limited number of CDM channels for receiving broadcast services. This allows for lower power consumption of receivers Narrow bandwidth enables low system clock frequency Provision of interactivity Supports hypertext linkage using mobile telecommunication network and Internet MPEG-4 BIFS provides overlay of animated text and graphics objects upon natural scenes Supports OMA RME for overlay of animated text and graphics objects BML supports both local and bidirectional interactivity BML supports both local and bidirectional interactivity BML supports both local and bidirectional interactivity Interoperability with mobile telecommunication networks Support for traditional and mobile telecommunication network and Internet, e.g. IMT2000 networks, IEEE 802.1x, etc. Support independent of any bearer layer for mobile telecommunication network and Internet for both IPv4 and IPv6. Delivery networks such as communication or broadcasting network are clearly identified Delivery networks such as communication or broadcasting network are clearly identified Delivery networks such as communication or broadcasting network are clearly identified Same solutions, optimized for handheld device reception, used to enable delivery of services over both broadcast and mobile cellular networks (3GPP) 5A (end) User requirements Multimedia System “A” Multimedia System “B” Multimedia System “C” Multimedia System “E” Multimedia System “F” synchronized synchronized
b) Monomedia coding (cont.): – Audio Audio: – HE AAC v2 – AMR-WB + (Optional for improved low data rate and especially speech service performance) Audio: – HE AAC v2 – AMR-WB + (Optional for improved low data rate and especially speech service performance) Audio: – HE AAC-v2 Audio: – HE AAC v2 – AMR-WB + (Optional for improved low data rate and especially speech service performance) – Other Data format: – 3GP and MP4 file – JPEG, GIF, PNG – Character encoded (3GPP Timed text) or bitmap based subtitling Data format: – 3GP and MP4 file – JPEG, GIF, PNG – Character encoded (3GPP Timed text) or bitmap based subtitling Data format: – MPEG4 files – JPEG – BMP – text subtitles based on 3GPP – Auxiliary data capability providing extensibility to support of additional data Data format: – 3GP and MP4 file – JPEG, GIF, PNG – Character encoded (3GPP Timed text) or bitmap based subtitling Flexible configuration of services: – – Ancillary and auxiliary data – Real-time audio and video – Digital – Scheduled content and file download/file carousel – Electronic Service Guide (ESG) – Subtitling (synchronized hypertext with A/V) – Real-time audio and video – Digital radio – Scheduled content and file download/file carousel – Electronic Service Guide (ESG) – Subtitling (synchronized hypertext with A/V) – Real-time audio and video – Scheduled content and file download based on network load – IP data streams – Electronic programme – Real-time and video – Digital radio – Scheduled content and file download/file carousel – Electronic Service (ESG) – Subtitling (synchronized hypertext with A/V) TABLE 5B (continued) User requirements Multimedia System “H” Multimedia System “I” Multimedia System “M” Multimedia System “T2”
ESCR_flag 1 ‘0' ES_rate_flag 1 ‘0' DSM_trick_mode_flag 1 ‘0' additional_copy_info_flag 1 ‘0' PES_CRC_flag 1 ‘0' PES_extension_flag 1 ‘0' PES_header_data_length 8 if (PTS_DTS_flags = = '10') { '0010' 4 PTS [32..30](1) 3 Marker_bit 1 PTS [29..15] 15 Marker_bit 1 PTS [14..0] 15 Marker_bit 1 } if ( PES_extension_flag = = '1') { not used } 10 (end) Syntax Number of bits Restrictions for (i=0; i<N1; i++) { Stuffing_byte 8 } for (i=0; i<N2; i++) { PES_packet_data_byte 8 } } } (1) The PTS field is included in a PES header only when the encapsulated SL packet header contains an OCR. Otherwise, the PTS field is not used. The following rules are applied at the transmitting side in order to allow random accesses at the receiving side: – A PAT (Programme Association Table) shall describe only one programme, and its transmission period shall be no greater than 500 ms. – A PMT (Programme Map Table) shall have the structure shown in Table 11 and adhere to the following rules: – A group of descriptors with Restriction “A” in the Table shall include an IOD_descriptor. – A group of descriptors with Restriction “B” in the Table shall include an SL descriptor for an ES_ID.
handovers: dual-mode receivers may receive content on one or the other technique seamlessly. 4 Specific issues addressed by DVB-SH 4.1 Reception conditions and DVB-SH features 22 summarizes the reception conditions addressed by DVB-SH, across the different types of environment (rural, urban or suburban). For each case, the characteristics and typical parameters of the channels are given, with the relevant DVB-SH features. TABLE 22 Reception conditions addressed by DVB-SH Reception condition Situation Characteristics Environment Coverage Channel characteristics Typical channel parameter and relevant DVB-SH features Reception Condition A Outdoor pedestrian Up to 3 km/h Rural Satellite Stationary: Low delay/low spread. LOS:AWGN/Rice K > 10 dB: Additional margin to cope with fading. For shadowed, K < 7 dB: time interleaving to mitigate effects. Low speed: large signal variation. LMS channel model at low speed: Time interleaving. Urban Terrestrial Stationary: Rayleigh/very low Doppler. TU6 channel: low code rate improves; antenna diversity also improves. Low speed/Rayleigh/low Doppler. Higher margins to cope with slow fading effects. Suburban Terrestrial, Combined or integrated For terrestrial same as above. For terrestrial same as No combined or integrated channel available. No combined or integrated channel model available. Reception Condition B1 Up to 3 km/h, lightly shielded building Rural (1) Terrestrial Channel is the same as Reception A with high penetration margins. TU6 channel: low code rate improves; antenna diversity also greatly improves. Suburban Terrestrial, Combined or integrated Same as above for terrestrial. No combined or integrated channel model available. Reception Condition B2 Up to 3 km/h, highly shielded building Rural (1) Urban Terrestrial Channel is the same as Reception A with higher penetration margins as in B1. TU6 channel/low code rate improves; antenna diversity