6.3-1

Implementation of a Global Mobile TV System

Yong-Suk PARK, Se-Ho PARK, Kyung-Taek LEE, Jong-Ho PAIK, and Jong-Moon CHUNG Korea Electronics Technology Institute and Yonsei University, Seoul, Korea

Abstract--This paper presents an implementation of a multi-

standard global mobile TV system. Audio, video, and data services provided by the different digital broadcasting mobile TV standards available today are decoded on a single, unified platform.

I. INTRODUCTION

Mobile TV is viewed as an opportunity by many, offering diverse new services in addition to TV services that can act as sources of revenue [4]. Different digital broadcasting mobile TV standards have been developed and deployed, such as Digital Video Broadcasting – Handheld (DVB-H), 1-Segment Integrated Services Digital Broadcasting – Terrestrial (1-SEG ISDB-T), and Terrestrial Digital Multimedia Broadcasting (T-DMB) [1]-[3]. As a consequence, consumers have to deal with incompatibility issues. Device manufacturers are also affected since different types of receivers have to be made for each target market, leading to production cost increase. This paper describes the implementation of a global mobile TV system which supports the previously mentioned standards on a single platform, effectively making the technologies used behind the service transparent to the users.

II. IMPLEMENTATION

A. Hardware

The system consists of a multi-standard receiver module and decoder platform as shown in Fig. 1. A single-chip mobile TV system on chip1 (SoC) which combines a channel decoder with an RF tuner is used for the receiver module. The mobile TV SoC integrates into a single chip a low-noise amplifier (LNA), embedded SRAM, analog-to-digital converter (ADC), PLL, CPU, and a low dropout (LDO) regulator, thereby reducing the number of external components needed. The part complies with standard specifications for DVB-H, 1-SEG ISDB-T, and T-DMB. The chip operates in one of the mobile TV modes depending on pin and register settings. The integrated built-in multi-band RF tuner supports VHF (174-240 MHz), UHF (470-862 MHz), and L-bands (1350-1750 MHz). The chip is fabricated in 65nm process technology and housed in a 5 mm x 5mm wafer-level chip scale package (WL-CSP).

The decoder platform2 uses a mobile application processor that combines a 32-bit processor core, clocked at up to 634

MHz, and hardware blocks for multimedia processing. An embedded Multi Format Codec (MFC) on-chip supports encoding and decoding of MPEG4/H.263/H.264 and decoding of VC1 video formats. The hardware H.264 is used to decode the mobile video broadcast. The application processor also incorporates many hardware peripherals, such as camera interface, LCD controller, USB host, SD card interface, etc. to reduce total system cost and enhance overall functionality. The decoder platform interfaces with the receiver module via the serial peripheral interface (SPI) and operates in master mode.

1The mobile TV SoC is commercially available as Samsung Electronics S3C4F60.

2The decoder platform uses Samsung Electronics S3C6400X application processor.

Fig. 1. Global mobile TV system block diagram.

B. Software

The software architecture of the global mobile TV system is shown in Fig. 2. The software developed is modular so undesired service or code blocks can be disabled or removed. An embedded operating system runs on top of the decoder platform. A device abstraction layer is implemented to make the software portable and independent of hardware details.

The PSI/SI Controller block manages the tables associated with Service Information (SI) and MPEG-2 Program Specific Information (PSI) for DVB-H, 1SEG ISDB-T, and T-DMB. The FIG/FIDC Controller manages ensemble and service information for T-DMB. The information obtained from these

978-1-4244-2559-4/09/$25.00 ©2009 IEEE

blocks is processed by the EPG/ESG Engine to generate electronic program guides.

MPEG2 TS Demultiplexer block is used to get mobile TV

data stream for 1-SEG ISDB-T and T-DMB in the form of 188-byte transport stream (TS) packets. Streaming Protocol Stack block is used to get data stream for DVB-H in the form of IP datagrams. The Audio Video Player, Render Engine, Audio Decoder blocks are common to all mobile TV modes, and they process the audio and video elementary streams extracted. The Audio Decoder supports MPEG-1 Audio Layer II for Digital Audio Broadcasting (DAB) digital radio and MPEG-4 Advanced Audio Coding (AAC) for mobile TV audio. The following codecs are supported under MPEG-4 AAC: Low Complexity AAC (LC-AAC), High-Efficiency AAC (HE-AAC), and Bit-Sliced Arithmetic Coding (BSAC). BSAC uses an alternative noiseless coding to AAC and is used in T-DMB configurations for Korea. The Caption Engine provides captioning capabilities for 1-SEG ISDB-T. The Render Engine combines caption data with the decoded video.

The software processes data services for T-DMB only at the moment. Dynamic Label Segment (DLS), JPEG Slideshow, Broadcast Website (BWS) are some of the data services available.

III. RESULTS

The developed system was tested for broadcast reception for each of the mobile TV standards supported in a laboratory environment. Reception of live commercial broadcast was tested for T-DMB and 1SEG ISDB-T. Fig. 3 shows the implemented global mobile TV platform decoding T-DMB broadcast.

The implemented software blocks have been functionally

verified. Code optimization is currently being performed to

enhance performance. Table 1 shows the initial system performance measurement for each mobile TV standard. The application processor runs at 400 MHz. BSAC is used for T-DMB audio and AAC for the others. The software H.264 performance is shown for video. The system can alternately use the hardware video decoder in the application processor for enhanced performance. The “Total” category includes the Common Demux, System & Channel, Data, and Caption Engine blocks, in addition to audio and video.

Fig. 2. Global mobile TV system software architecture.

Fig. 3. Global mobile TV platform implemented.

IV. CONCLUSION

A global mobile TV platform was developed by using a single-chip mobile TV SoC. In addition, standards-converged and modular system software was developed to decode the services provided by the different mobile TV standards. The developed system provides device manufacturers the flexibility to support the most popular mobile TV standards and broadcast frequency spectrums around the world using a single platform. It can be applied to applications such as global roaming world phones, giving mobile TV service access to users irrespective to their global location.

REFERENCES [1] ARIB, "Transmission system for digital terrestrial television

broadcasting," ARIB standard, STD-B31 Version 1.6, Nov. 2005. [2] ETSI, "Digital audio broadcasting (DAB); DMB video service; user

application specification," ETSI standard, TS 102 428 v1.1.1, Jun. 2005. [3] ETSI, "Digital video broadcasting (DVB); DVB-H implementation

guidelines," ETSI standard, TR 102 377 v1.2.1, Nov. 2005.

TABLE I PERFORMANCE

Standard Audio (MIPS)

Video (MIPS)

Total (MIPS)

Memory Usage (byte)

1SEG ISDB-T 16 96 116 2,876K DVB-H 16 114 132 3,024K T-DMB 33 180 218 2,936K

[4] C. Y. Yeun, "Mobile TV technologies," in ITI 5th International Conference on Information and Communications Technology, 2007, pp. 2-9.