1
ISDB-T Transmission Technology
- Single transmission for fixed, vehicular, and handheld receivers -
Kazunori Yokohata
NHK (Japan Broadcasting Corporation) Science & Technical Research Laboratory, Tokyo, Japan
yokohata.k-jm@nhk.or.jp
I. Broadcasting system and services going digital
On December 1, 2003, Japan launched
digital terrestrial television broadcasting (DTTB)
using the Integrated Service Digital Broadcasting
– Terrestrial (ISDB-T) transmission system that
is based on Orthogonal Frequency Division
Multiplexing (OFDM).
ISDB represents a set of digital
broadcasting standards in Japan covering
terrestrial, satellite, and cable transmission that
share a common format for multiplexing which
enables transmissions of high-definition
television as well as data broadcasting. Digital
broadcasting provides a wide range of convenient
services, owing to its high picture and sound
quality, interactivity, and storage capability. It is
also set to become a foundation on which anyone
in the country will be able to benefit from
participating in the information and
communications technology (ICT) society through
one of the most familiar and easy-to-use devices,
the television. Japan is in the process of digitizing
every broadcasting media, including satellite
(ISDB-S), terrestrial (ISDB-T), and cable TV
services (ISDB-C) [1]. This paper describes
ISDB-T digital terrestrial television broadcasting.
The history of ISDB goes back to the
idea of a digital broadcasting system for the 21
st
century as conceived at the NHK Science and
Technical Research Laboratories (STRL) in the
1980s. Envisioning the new age of digital
terrestrial broadcasting, NHK developed the
Band Segmented Transmission – Orthogonal
Frequency Division Multiplexing (BST-OFDM)
transmission scheme of ISDB-T in 1996. Based on
the requirements specified by the
Telecommunication Technology Council (TTC),
NHK and Advanced Digital Television
Broadcasting Laboratories (DTV-Lab) presented
a joint proposal for the ISDB-T system to the
Association of Radio Industries and Businesses
(ARIB). In 1997, the proposal was designated the
draft standard for Digital Terrestrial Television
Broadcasting (DTTB) by the TTC. In 1998, field
trials for the draft standard were carried out by
NHK, and the results of the trials were
contributed to ARIB. After discussions in ARIB,
the Final Draft Standard for DTTB was approved
by the TTC in 1998. Large-scale field trials for the
Final Draft Standard using Tokyo Tower were
carried out from October 1998 to March 1999 in
order to verify the performance in a practical
digital-service area. The ISDB-T system was
found to offer superior reception characteristics.
Consequently, in 1999, it was adopted as Japan’s
DTTB system [2].
II. Transmission System for ISDB-T
As mentioned above, ARIB in Japan
decided the specifications for ISDB-T [3]. The
ISDB-T transmission system is also
recommended in Recommendation ITU-R
BT.1306-3 [4], and its planning criteria are
recommended in Recommendation ITU-R
BT.1368.
This section briefly describes the
transmission scheme of the ISDB-T system [5].
Table 1 shows the related ARIB standards and
ITU-R recommendations for ISDB-T.
Table 1 ARIB standards and ITU-R recommendations for ISDB-T
Contents
ARIB
Standards
ITU-R
Recommendations
MPEG-2 Video (ISO/IEC 13818-2) STD-B32 BT.1208
MPEG-2 AAC (ISO/IEC 13818-7) STD-B33 BS.1115
BML(XHTML), ECMA Script STD-B24 BT.1699
MPEG-2 Systems (ISO/IEC 13818-1)
STD-B10,
STD-B32
BT.1300,
BT.1209
Multi 2 STD-B25 ---
ISDB-T transmission STD-B31 BT.1306-3 System C
ISDB-T receiver STD-B21 ---
ISDB-T broadcasting operation TR-B14 ---
Item
Video coding
Audio coding
Data broadcasting
Receiver
Operational guideline
Multiplex
Conditional access
Transmission