Broadcast television systems are formatting some specific standards and encoding them to transmit and accept terrestrial television signals. It is a form of communication which is used in the distribution of contents like videos and audios to audiences all over the world. The traditional methods used like AM and FM analog radio, SECAM are now outdated. These signals are upgraded to RDS/HSDS signals so that it can accommodate 16:9 aspect ratio of videos. The traditional TV broadcast systems include Analogue Terrestrial TV, Digital Satellite TV, Cable TV with both analog and digital systems. The newer technologies have incorporated Cloud-based TV broadcasting and include Digital terrestrial TV (DTTV), Pay-per-view, Video-on-demand, High Definition Television (HDTV), IPTV and Web TV. Let us see the newer ones in detail.
- Digital Terrestrial TV
Digital Terrestrial TV is executing the technology used in digital television. It provides with more number of channels and better-quality videos and audios. The aerial broadcasts are directed to an aerial antenna instead of any cable connection or satellite dish which helps in providing quality content. In Europe, the DVB-T technology is used, and it is immune to any distortion due to multiple paths. The signals are transmitted on a frequency of radio via airwaves as it is done in conventional analog televisions. The primary difference is that multiplex transmitters are used to receive signals from different channels within a range of single frequency like UHF or VHF channel. Since a modulation method is implemented by the channel, more amount of data can be sent. In DVB-T, the modulation is done by 16 or 64 state Quadrature Amplitude Modulation (QAM) and method used is COFDM. A 64 QAM channel can transmit signal at a higher bit rate but also is prone to more interference. So, usually, 16 and 64 QAM are integrated to form a single multiplex and is known as hierarchical modulation. This reduces the degradation, and hence the quality is not compromised.
The high-definition television is also known as HDTV. It provides with better quality content compared to other traditional ones like SECAM, NTSC, and PAL. The signals are transmitted digitally, and the standards that are followed currently are defined by U-R BT.709. The 1080p i.e progressive, 1080i i.e. interlaced and the 720p comes in 16:9 aspect ratio screen format. It has more lines, which enables it to provide with better image quality and resolution than that of any other standard television. The scan lines are placed closer to each other, and the gap is not even visible to naked eyes which makes the picture almost 2 to 5 times sharper. The improvement in picture quality is directly proportional to the size of the television used. If the size is small, you might not be able to distinguish any difference in picture quality it provides with that of traditional ones. The 1080i scanning method divides the 1080 lines of resolution into two pairs. The first pair of alternate 540 lines is painted in a single frame, and rest 540 is painted on another frame. The 1080p i.e. progressive scanning displays and paints all the lines on a single frame which mean a greater bandwidth is required.
The TV over Internet Protocol has been a recent introduction and almost a revolution in the TV industry. The problems that were faced with distribution network due to coaxial cables like degradation of signals, less capacity of the transmission of the band, signal levels, interference are eliminated. Several interfaces are integrated into a multi-service unit with the help of IP. This sets a platform referred to as the triple play. This has helped to make progress in distributing videos with high quality and a huge audience.
New forms of broadcasting are invented since the traditional ones were not able to meet the demands of the huge audience. Broadcasters are aiming to provide high-quality contents like 4K which are compatible with every device. Click here to read more.