Published on October 17, 2007
T-DAB Presentation: T-DAB Presentation Intercontinental Hotel, Nairobi, Kenya 19th December 2006 Eng. Leo K. Boruett ASSISTANT DIRECTOR FREQUENCY PLANNING COMMUNICATIONS COMMISSION OF KENYA SCOPE: SCOPE Introduction T-DAB technology Digital Radio Standards T-DAB EUREKA 147 T-DAB Version 2 Limitations of T-DAB Implementations of T-DAB Conclusions Wayforward Introduction: Introduction Terrestrial - Digital Audio Broadcasting (T-DAB) is a technology for broadcasting audio programming in digital form, designed in the late 1980s in Europe by a consortium of broadcasters. Commercial T-DAB receivers began to be sold in 1999. The RRC-06 conference established a plan for (T-DAB) Terrestrial-Digital Audio Broadcasting in the frequency bands 174 - 230 MHz (VHF Band III) T-DAB technology: T-DAB technology T-DAB is a digital radio broadcasting system, that through the application of multiplexing and compression techniques, combines multiple audio streams onto a single broadcast frequency called a T-DAB Multiplex. Within a T-DAB multiplex, individual stations can be allocated different bit rates. The number of channels within a T-DAB multiplex can be increased by lowering average bit rates, but at the expense of the quality of streams. Error correction under the T-DAB standard makes the signal more robust, but also reduces the total bit rate available for streams. Receivers separate and decode the signals in the digital stream. Digital Radio Standards: Digital Radio Standards The Eureka 147 standard of T-DAB technology is coordinated by the World DMB Forum, which represents more than 30 countries. The United States has opted for a proprietary system called HD Radio). Japan is also broadcasting digital radio but using a different system called Integrated Services Digital Broadcasting. Digital television services also incorporate some digital audio channels on spare bandwidth using DVB-T and DVB-H standards. T-DAB EUREKA 147: T-DAB EUREKA 147 Frequency Bands T-DAB can use the following frequency bands for broadcasting: VHF Band III – Frequency band 174–240 MHz L-Band – Frequency band 1452–1492 MHz Each T-DAB Multiplex utilises 1.75 MHz spectrum. Therefore in one 7MHz channel in VHF band III, you can accommodate 4 T-DAB multiplexes. For example, Channel 12 has T-DAB Multiplexes 12A,12B,12C,12D. T-DAB EUREKA 147: T-DAB EUREKA 147 Services Various different services are embedded into one Multiplex: Primary services, like main radio stations Data services Electronic Programme Guide (EPG) Collections of HTML pages and digital images Slideshows, which may be synchronised with audio broadcasts T-DAB EUREKA 147: T-DAB EUREKA 147 Multiplex capacity The data transfer rate for a T-DAB Multiplex (1.75MHz) will be approximately 1.2 Mbit, and is able to provide: five CD quality programs; or six FM quality services; or 12 AM quality services In the UK, most services transmit use 'protection level three', being an FEC of 0.5 which equates to a maximum bit rate per multiplex of 1152 kbit/s. The typical bitrate per audio channel ranges from 160 kbit/s to 192 kbit/s ‘T-DAB version 2': ‘T-DAB version 2' WorldDMB has announced that T-DAB would be adopting the HE-AAC audio codec, which is also known as AAC+. Receivers that support the new T-DAB standard will be released in the UK in 2007. The new HE-AAC audio format is around 3 - 4 times as efficient as the old MPEG-1_Audio_Layer_II audio format. Limitations of T-DAB: Limitations of T-DAB Lack of global agreement on standards. Several T-DAB schemes are being promoted in the United States and Japan, none of which is compatible with the "Eureka 147" The improved HE-AAC codec for T-DAB is not backwards compatible, leaving early T-DAB adopters with incompatible hardware. T-DAB chipsets have never been power efficient. Revised T-DAB 2 AAC+ chipsets are projected by manufacturers to be up to 7 times more power efficient, increasing battery life for portable radios by a factor of approximately three. Implementations of T-DAB: Implementations of T-DAB Australia In October 2005, Australia adopted the Eureka 147 system. The Australian Government has set 1st January 2009 as the launch date for digital radio in the country. Austria In Austria so far there is a test operation of T-DAB by the national broadcasting company. Up to now no decision on a date for starting with commercial transmissions has been taken. Belgium T-DAB was launched in Belgium in 1997. Investments in new T-DAB services and more networks are expected, especially for the commercial and regional networks. An upgrade of the transmitter network for excellent indoor coverage is planned. Implementations of T-DAB: Implementations of T-DAB Canada Currently, the national broadcaster operates commercial T-DAB stations in in many parts of the country. China China already broadcast some T-DAB programs at Beijing and Guangdong. Czech Republic There is currently no T-DAB coverage in the Czech Republic.The digital radio stations are currently transmitting via DVB-T and the Internet. The process of issuing T-DAB licences commenced on autumn 2006. Implementations of T-DAB: Implementations of T-DAB Denmark In Denmark, an extensive rollout of T-DAB has been made by the national public broadcaster. 700,000 Danes (13%) had access to a T-DAB radio in 2006. The goal is that the entire country should be covered in 2007 Finland Finland switched off their T-DAB transmitters in 2005. Finland is now investigating providing digital radio via other digital broadcasting systems, such as DVB-H. France Only one VHF T-DAB assignment is implemented. In France, T-DAB is implemented in L-band. However, for the future digital Plan, France has decided to implement T-DAB in Band III. The five largest French radio broadcasters are currently participating in a trial of the DVB-H digital broadcasting system in Paris. Implementations of T-DAB: Implementations of T-DAB Germany After some years of test operation, regular T-DAB service was launched in April 1999. At present about 85% of the German households are located within the service area of T-DAB transmitter networks. However, the market penetration of receiver equipment is still considered low. Indonesia Indonesia began T-DAB trial transmission in August 2006 on four radio stations. Implementations of T-DAB: Implementations of T-DAB Ireland Ireland's national broadcaster completed T-DAB trials on 13th July 2006. T-DAB development is limited, at least in the short term, by the lack of Band III frequencies - only 12C is allocated for the entire country, with 12A allocated to commercial broadcasting. 11B, 11C, 11D and 12D are also allocated to regional services, but collision with Band III television and Northern Irish T-DAB allocations make these mostly unusable for the time being Korea On 1st December 2005, South Korea launched its T-DMB service which includes both television and radio stations. T-DMB is a derivative of T-DAB with specifications published by ETSI. Implementations of T-DAB: Implementations of T-DAB Malta T-DAB spectrum licenses were awarded in March 2006 on 3 T-DAB band III frequency blocks. The Netherlands In March 2005, Netherlands postponed plans to push ahead with rolling out T-DAB, and will instead wait for new technologies to arrive so that they can be assessed. The new technologies, which include the new version of T-DAB, DRM+ and DVB-H, are much more efficient than the current version of T-DAB. New Zealand New Zealand is trialing T-DAB since November 2006 in Wellington and west Auckland. Implementations of T-DAB: Implementations of T-DAB Norway More than 15 stations are available on T-DAB. T-DAB radio in Norway is divided into a national multiplex on channel 12D, and several regional multiplexes. The first test transmissions were started in the middle of the 1990s. As of 26th November 2006, the T-DAB coverage was 80% of the population. Norway aims at reaching full national DAB coverage before 2014. However, FM is by far the most common method of radio distribution. Poland Poland plans to accommodate three national T-DAB layers and one national DVB-T multiplex. There are also considerations to implement DMB and DVB-H. The public broadcaster intends to locate its own audio services within the DVB-T multiplex. Implementations of T-DAB: Implementations of T-DAB Romania As of summer 2005, in Bucharest there is a single emitter that broadcasts five radio stations multiplexed on channel 12A (223,936 MHz - Band III). The five digital radio stations are three public service and two commercial service. Russian Federation There are no T-DAB transmitters working at present time, but there are plans to grant two licences for commercial T-DAB broadcasting services. Singapore In Singapore, T-DAB was launched in 1999. Using the Eureka 147 T-DAB system, the system provides six digital-only stations and eight simulcast FM services, along with images and text to supplement the audio. Singapore was the first country to reach full T-DAB coverage. Implementations of T-DAB: Implementations of T-DAB Sweden On 27th November 2006, the Swedish government freezed further investment in T-DAB, citing that T-DAB was very expensive to transmit and that cheaper digital radio systems should be investigated, and digital radio should also be transmitted via the Internet and via the digital terrestrial TV system. Switzerland In 2005, the North-Eastern parts of Switzerland were covered by T-DAB services. In 2006, Central Switzerland was added to the T-DAB reception area. By 2010, T-DAB will be available in all of Switzerland. Implementations of T-DAB: Implementations of T-DAB United Kingdom Currently, in the UK, the public service broadcaster, the BBC, has covered about 85% of the population. Coverage of commercial national T-DAB Digital Radio is at 88% of the population. A low cost silicon chip that was recently developed is used in the majority of receivers is believed responsible for T-DAB receiver prices falling to as low as £30 in 2006. About 90 UK local radio stations are either unable to transmit on T-DAB because there is no space for them on a local T-DAB multiplex or because they are unable to pay the high transmission costs of T-DAB. Implementations of T-DAB: Implementations of T-DAB United States of America While terrestrial T-DAB did not take off in USA, satellite DAB radio systems have been developed, each offering "CD quality" audio and about a hundred channels. In recent years, satellite radio has grown to make a name for itself by providing non-subsciption, all-digital music channels that are similar to local terrestrial broadcast offerings. Conclusions: Conclusions The T-DAB technology has not been implemented widely, although it has recently experienced a substantial growth in the UK market. The spectrum planned for T-DAB will be available once the existing analogue television services in the targeted band have been migrated to Digital broadcasting. In view of the limited spectrum in the targeted VHF band III, and in order to accommodate as many broadcasters as possible, the T-DAB service is planned to be licensed on the basis of a multiplex operator model. Wayforward: Wayforward CCK will continue to follow the progress on the development of T-DAB services and other competing technologies such as the new version of T-DAB, DRM+, DVB-T and DVB-H services, and make a decision on the way forward once the trend of the implementation of these technologies and services becomes clear.