“Dab ratio” is definitely an unfamiliar definition for many people. So today, Viknews.com will share with you the basics of DAB – Digital Audio Broadcasting, a form of radio technology that is being used in many countries around the world. Let’s read the following article to answer the question what is dab ratio and find out what is advantages of dab technology.
What is dab ratio?
Dab ratio’s definition
DAB Digital Radio, also known as digital audio broadcast, is a completely new system for broadcasting and receiving stations.
As its name, signals broadcast in a digital format allow CD quality to be achieved. Those who have listened to the digital radio DAB have commented on the significantly better sound quality and “presence” of the new radio system. Also, it does not suffer from the multiple effects often experienced on FM transmissions and the system uses what it is called a single frequency network (SFN) without having the necessary retuning when moving from a next coverage area.
In addition, many new services can be implemented on digital radio stations that allow new systems to fit into the 21st century. Digital radio signals carry data along with sound, and this allows text and images to be transmitted with sound to enhance the listening experience. In this way, it can convey the title of a song, and a photo of the artist while some music signal is being transmitted. It can also move news on the bottom of the screen used on radio stations. DAB digital radios are now established in many countries around the world from the United Kingdom and Europe to Canada, Australia and many other countries.
The digital dab ratio construction
In order to produce a digital system that satisfactorily operates according to the conditions required for digital radio, a large number of jobs have been performed during the development phase. A number of current digital techniques have been studied but it has realized significant limitations for this application.
One of the main problems is that many recipients will use non-directional antennas and as a result, they will receive a reflected signal. These will be delayed enough for the faulty data. Also, the bandwidth required to accommodate a full stereo signal will need to be reduced to ensure efficient use of the spectrum.
The technical standards for digital radio were developed under the auspices of the European Eureka Project 147. The group includes manufacturers, research stations and network operators. There are two main areas of the system that are interested in digital broadcasting: that is the modulation system and the digital audio coding and coding system.
The encryption and compression system is very important for the system to be able to develop data rates that have been significantly reduced compared to standard CDs. Digital radio system adopts a data rate reduction of 128 kbits / sec, a sixth of the bit rate for quality is similar to the encoded linear signal to achieve input audio signal reduction be analyzed carefully. It is found that the ear can only hear a certain frequency threshold, if the sound is generated at a lower frequency then we will not be able to hear it.
Also if a high-frequency sound is played on a sound system, then the frequency is lowered, it may not be heard because the hearing threshold is modified. By analyzing the sound to and only encoding the components that the ear will hear, it will significantly reduce the amount of work to be done.
Advantages of DAB technology
Digital radio technology (DAB) promises to replace the analog technology with FM radio broadcasting in the near future because DAB technology was overcome many limitations of FM.
To broadcast FM, radio stations use frequencies from 88 to 108MHz. These stations must have a certain distance to avoid wave conflict, so the number of FM radio channels is limited. FM also cannot transmit signals over long distances. Meanwhile, DAB allows stations to transmit information in digital media in much the same way that mobile networks operate, including data compression and multiplexing. DAB creates a very wide channel, about 1,500MHz, then splits this channel into multiple streams for different service providers. DAB is not limited to the number of channels, only stations need to be far enough away from each other so that the signal does not conflict. With FM, the listener must memorize the frequency and detect. As for DAB, channels can be searched by pre-ordered names. Users need to purchase a DAB standard device to use DAB digital radio. In addition to DAB, there is DAB +, an upgraded version of DAB to support adding new audio decoding configurations as well as improving communication quality. In the future, with DAB technology, radio signals can accompany audio data, images, song names …
There are currently 3 other digital radio standards in addition to DAB, which are IBOC – HD Radio, Digital Radio Mondiale, ISDB-T. DAB is highly appreciated by the advantages of the number of programs broadcast on a channel, the ability to transmit data and provide added services.