BROADBAND TECHNOLOGY
BROADBAND TECHNOLOGY
Broadband is a type of data transmission in which a single medium (wire) can carry several channels at once. Cable TV, for example, uses broadband transmission. A more technical meaning reads: ‘Broadband refers to a transmission speed of 1.54 million bits per second or more using a single medium, such as a wire, that has two or more channels carrying information at once.’
Broadband is in the course of revolutionising network access. While some communications only send one signal down a wire, broadband send numerous channels al once, meaning lots more daia. In everyday use, broadband just means “high bandwidth”, and everyone is looking to deliver broadband access to consumers at home, to tele-workers, and to businesses. Broadband is new cable service, broadcasting that has a technology twist, telephony of tomorrow, Internet content that expands upon text, graphics, audio and still- frame video and interactive services delivered by wireless cable and satellite systems. Web video-on-demand, video Internet commercials, short-form videos and all manner of online entertainment, news and advertising are popping up more and more as broadband penetration increases.
Various Broadband Technologies
There are four main broadband technologies: ADSL, cable, satellite and terrestrial wireless.
ADSL (Asymmetric Digital Subscriber Line): It is a technology for transmitting digital information at high bandwidths on existing phone lines. Asymmetric Digital Subscriber Lines (ADSL) is used to deliver high-rate digital data over existing ordinary phone-lines. ADSL facilitates the simultaneous use of normal telephone services, ISDN, and high speed data transmission, eg., video. ADSL can transmit more than 6 Mbps to a subscriber-enough to provide Internet access, video-on-demand, and LAN access.
Cable: The fibre optics technology can provide nearly unlimited bandwidth potential and is steadily replacing copper network especially in intra-city backbone networks. This is being deployed in commercial buildings and complexes and some metros/big cities having high-density potential broadband subscribers.
Fibre-optic cable’s top selling point is its unparalleled capacity – a whopping 10 Mbps for both downloading and sending data is likely to be quite commonplace. On the downside, laying the fibre-optic cable is expensive and only those who live or work in urban areas are likely to be within striking distance of a cable node.
Satellite: Delivering data from space secure unsurpassed coverage of the planet, but is a one-way system – download only. The data download rates can be very fast, up to 35 Mbps, but more common will be 4 to 6 Mbps per channel, which would be shared between users.
Wireless: Many analysts see wireless data transfer, based on radio frequencies, being of greatest use within homes or offices. You could use your laptop at upto 11 Mbps in any room in the house, without having to have phone or cable ports in every room. Listed buildings, schools and hospitals could be given high-speed networks without any rewiring. However, making wireless data access available over larger areas is more difficult.
Broadband Policy 2004
Broadband connectivity: Keeping in view the present status. Broadband connectivity is defined as “An ‘always- on’ data connection that is able to support interactive services including Internet access and has the capability of the minimum download speed of 256 kilo bits per second (kbps) to an individual subscriber from the Point Of Presence (POP) of the service provider.
The estimated growth for Broadband and Internet subscribers in the country envisaged through various technologies is as follows:
Year Ending Internet Broadband
Subscribers Subscribers
2005 6 million 3 million
2007 18 million 9 million
2010 40 million 20 million
Benefits of Broadband Technology
Public safety: Emergency services-including firefighters, police forces and medical crews-see wireless broadband as a vital addition to their tools.
Health care: “Telemedicine” has long been one of the most promising applications for high-speed networks. Rural and outlying hospitals and clinics rarely have access to the expertise and experience of doctors in urban centres. But diagnoses and consulting can be done with the help of high- quality audio and video and of real-time data connections between central and remote facilities.
Education: Schools at all levels are already using high-speed Internet connections in teaching and research, and many see the networks as ways to help smooth out the radically unequal distribution of resources between different regions and institutions. Colleges provide access to course materials online, via streaming videos of lectures, for instance.
Faster Internet Service: Broadband will make it easier for consumers to get content from the Internet faster. In the case of two-way broadband technologies, all Internet access will be substantially faster. In the case of one-way broadband technologies, consumers will quickly access Internet content related to the TV programme that is “married” to the linear broadcast.
An “Always On” Connection: Broadband technologies will not require the user to wait to “log on” to the Internet. “Always on” will make it very convenient for consumers to access information quickly.
Interactive Video and Data Content: Broadband delivers video and data. Consumers will be able to receive data enhancements, including rich video, graphics and educational applications along with their traditional TV programming. Depending on how this data is delivered, the consumer will have a different experience with the content.
DIRECT-TO-HOME (DTH) BROADCASTING SERVICES
Direct-to-Home (DTH) satellite television is becoming a buzzword in the satellite broadcast industry due to the fact that DTH offers immense opportunities to both broadcasters and viewers. Thanks to the rapid development of digital technology, DTH broadcast operators worldwide have been able to introduce a large number of new interactive applications in the television market besides a large number of entertainment programmes over a single delivery platform. In addition, since digital technology permits a highly efficient exploitation of the frequency spectrum, the number of TV channels that can be broadcast using digital technology is significantly higher than with analogue technology. The increased number of television channels allows the operator to satisfy the demand of a number of niche markets with dedicated transmissions. Distribution of multi-channel TV programmes directly through satellites is commonly referred to as Direct-to-Home broadcasting services, and is offered in Ku (“kay-you”) band. This band refers to a portion of the electromagnetic spectrum in the microwave range of frequencies i.e., from 11.7to 12.7 GHz. This segment is used primarily for satellite communication because of its superior quality of transmission and stereo quality audio. Subscribers will have to install a small dish antenna, measuring about 18 inches or even less in diameter, for receiving programmes directly from the satellite. But, a dish antenna alone is not enough for availing of the facility of DTH programmes. In addition, the subscriber requires a set-top box as well.
Transmission in Ku band is most appropriate and widely used for the purpose. All the encoded transmission signals are digital – thus providing higher resolution picture quality and better audio than traditional analog signals. All the advantages of the digital transmission, as applicable to the terrestrial transmission are relevant in the satellite transmission also.
DD Direct Plus
“The world’s first free-to-air direct-to-home television service” was launched by the Prime Minister, Manmohan Singh in New Delhi on December 16, 2004. It will cover the entire country except the Andaman and Nicobar Islands. Direct-to- Home (DTH) broadcasting services are a relatively recent development in the world of television (TV). In early 1980’s, the development and use of DTH satellite receivers became a popular alternative for people in rural areas, not served by broadcasters or cable network, to receive TV programmes which were earlier available in urban areas only.
The Government permitted DTH broadcasting in India on November 2, 2000. The primary reason for the Government to have permitted DTH broadcasting seems to be its proven capability of serving rural areas as well as population scattered over vast distances in remote and inaccessible hilly terrains. Telecom Regulatory Authority of India (TRAI) is also the regulatory body for broadcasting industry, in addition to telecommunications.
Karnataka is among the States that have been chosen for the implementation of a pilot project on the Direct-to-Home (DTH) platform of Doordarshan on October 6,2004. Himachal Pradesh, Gujarat, Uttaranchal and Rajasthan are the other States, apart from the North-Eastern region and Chandigarh. These States were selected because the coverage of television is less than the national coverage.
The biggest drawback, according to experts, is that in about 80 million TV homes in the country, nearly one-third of the television sets are so outdated that they can receive just about 10 channels.
In addition, these sets do not have the state-of-the-art technology compatible with that of a set-top box.
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