Digital Video Broadcasting

Digital Video Broadcasting (DVB) is the most popular group of specifications to broadcast digital television, used all over the world through various transmission media. DVB has many standards, each suited for a specific transmission media. Each DVB standard is made in order to broadcast and receive in the most suitable and convenient way for that transmission media.

Here I will mention a few of the DVB standards and describe them briefly:-

Digital Video Broadcasting over Terrestrial networks (DVB-T)
DVB-T uses MPEG-2 or MPEG-4 (H.264) for broadcasting. This system is used worldwide for broadcasting free to air channels. It is mostly used by national broadcasters. Around the world, many countries have made it a law to upgrade national television to digital, the deadline being around 2009-2015. After the deadline, all analogue networks will be forced to shut down in these countries. The same also applies to radio networks, but those are not being discussed here.

In the U.K. (where I am now), the government has ordered the public and the broadcasts to "Switchover to Digital" by 2012. In 2012, all analogue networks will be shut down. Therefore the people are moving to services such as Freeview (also DVB-T) and Sky (pay television DVB-S) in order to avoid wasting money on a new television set or separate digital tuner.

Other countries too are making "switchovers" and moving to digital.

In Sri Lanka - Rupavahini Corporation announced a few years ago that they will go digital by 2008. But afterward, plans seemed to be cancelled and nothing seems to be upgraded. But behind the scenes, Dialog Telekom and another group called Sumathi have obtained licenses to broadcast digitally. Sumathi is already quietly broadcasting 4 channels, whilst Dialog is testing their systems with local channels. Dialog will soon launch a pay television service through DVB-T in Colombo and soon in other parts of the country, providing around 40 channels including 6 local channels (the ones already on Dialog Satellite TV). But no sign of national television broadcasters going digital themselves. Same applies for the radio broadcasters.

Digital Video Broadcasting over Multichannel Multipoint Distribution Service (DVB-MC)
All right, this system is basically Microwave broadcasting using MMDS. But in digital. This system uses the UHF frequencies, and broadcasts in MPEG-2 or MPEG-4. I've mentioned it here because of its presence in Sri Lanka.

In Sri Lanka - MMDS is used by the pay television operator Comet Cable in analogue form. But the service has been planning and promising to upgrade to DVB-MC for ages now. The latest promise is to upgrade by September 2007. But nobody can really be sure this will happen, as many false promises have been given before. But we should wait and see what happens.

Digital Video Broadcasting over Satellite networks (DVB-S and DVB-S2)
This technology is used for satellite television worldwide. It can be used with MPEG-2 or MPEG-4 encoding (nothing new). The newer version of the standard, DVB-S2, provides more features and facilities to save bandwidth and give more interactivity.

In Sri Lanka - Dialog Satellite Television, TV Lanka and Srilakvahini. These are the main companies which broadcast using DVB-S in Sri Lanka. Dialog TV is possibly planning to upgrade to DVB-S2 soon (not sure though).

Digital Video Broadcasting over Cable networks (DVB-C)
This standard allows for unlimited broadcasting of channel over a cable network. There is simply no limit to the number of channels broadcasted, and the total bandwidth is only the maximum of the cable used. That means the total bandwidth can fit almost two HDTV channels simultaneously on a coxial cable. Imagine the bandwidth and possibilities with a fibre optic network!

The high bandwidth allows for the best picture quality and sound quality possible. And there is little cost in operating a cable network, resulting in a very low price of pay television on cable networks.

In Sri Lanka - The cable television network Lanka Broadband Networks (LBN) uses DVB-C in its digital network. LBN is speedily expanding their channel collection and their only limit is coverage. They are the best pay television network in Sri Lanka because of this.

Digital Video Broadcasting for Handheld devices (DVB-H)
This standard uses almost the same technology as in DVB-T. However, the DVB-H television is suited to be used on battery powered devices with limited processing power and small screens. DVB-H allows for devices such as mobile phones to view television without wasting battery power.

Many countries have already deployed DVB-H networks, and many mobile phones already support the system (including some phones in the Nokia N Series).

In Sri Lanka - Dialog is planning to launch a DVB-H network soon.

End of Road for Comet Cable?

This topic has been going round for ages, but now we are reaching the climax of the situation. Will Comet Cable (Ruhuna Multivision 2001) manage to solve its current problems? Will Comet ever go Digital? Will Comet subcribers ever know the truth about whats going on?

June 2007 is drawing nearer. Much too fast. Comet Cable subscribers (or at least who are left of them) are anxious to know what will happen. Last year, the TRC sent a letter to Comet Cable requesting to them to switch to a Satellite system or some other technology apart from Microwave broadcasting. This was because Comet's bandwidths are needed for SLT's WiMAX wireless internet system. The TRC threatened to take away Comet's license to broadcast if they would not switch by June 2007. This could have been done if there were not so many problems...

• Internal fights for leadership - these are now over, but have left scars on the face of the company
• Low customer base (and dropping further each day)
• Low finances
• Need to pay royalties to Southern Development Authority
• And therefore, the inability to transfer shares till royalties are payed
• Heavy competition from Dialog TV and LBN, for they all have better channel lineups
• Limited coverage of 50km aroung JAIC tower, Colombo (10km for best reception)
• Interference from other signals and even Microwave Ovens due to low quality "BBQ" grill
• Lasy useless staff in higher positions, and poor helpless customer service having to tell lies and get scolded
• Liers in higher positions of the company, trying to get the maximum out of whats left rather then keep going

How Comet will ever face these problems is a mighty question. Especially when nobody seems to be doing anything about it. The customers are helpless in this case, and this should not be the way of a proper service. Surely if Comet was doing something it would have leaked out by now. But all we get are false alerts from "Harrold" (real name should be Harold) and Scoobie.

At least the real Harold was nice enough to tell TV Radio Sri Lanka that he did not send those false messages. But E-Mails regarding other problems were not replied to.

So therefore, with Comet not revealing anything to its subscribers, we can come to a conclusion that this is the End of the Road for Comet Cable. The higher staff is just waiting to grab the money and escape. They are even asking for more ads on the channels to earn more. Its like a time-limited shopping spree. Get as much as you can before June 2007. Of course, the lower staff suffers and ultimately lose their jobs.

I express my deepest sorrow about this, and confess that throughout its lifetime, it was the pioneer of Sri Lankan Pay Television. It was also, so far, the only Pay TV operation to work non-stop, even though times of trouble, without any disturbances to the main broadcast. I guess they must have got used to it after a while. I hope that the customers go for alternatives LBN and Dialog TV and do not hold on for dear life on a sinking ship. Unless Comet springs up again...