Advantages of broadcasting system

1, which improves the transmission quality of audio signals.

Compared with the existing analog broadcasting system, due to the high reliability of the digital signal itself, its sound quality remains unchanged in both audio signal processing and transmission, which can maintain the quality of the studio. Therefore, compared with FM, its major audio indicators have been improved by hundreds or even hundreds of times, that is, it can reach the quality of "CD" that people often say.

2. High efficacy.

In addition, due to the high reliability and anti-interference ability of digital signal transmission, the sensitivity of the receiver can be made higher, which makes the requirements for transmission power much lower under the condition of realizing the same broadcast coverage requirements as the existing FM. According to our current broadcasting technology, its six sets of high-quality audio programs * * * are transmitted at the power of 1KW, which is close to the coverage of a set of FM broadcasting only using 10KW. It can be seen that the power efficiency of DAB is 100 times better than that of FM.

The substantial improvement of power efficiency not only means energy saving, but also greatly reduces the cost of building DMB stations. The reason is that the single channel of DMB can transmit up to six sets of high-power DMB programs, and the power level is very low. Therefore, compared with the transmission of six sets of high-power FM programs alone, on the one hand, the occupied room area is several times smaller, on the other hand, the capacity of auxiliary power systems such as power supply, voltage stabilization and air conditioning is also 100 times smaller, and the antenna feed system that needs a lot of investment is also much simpler, especially the cost of the new station is reduced and the construction period is shortened, which is very conducive to the large-scale popularization and use of DMB.

3. High spectral efficiency

As mentioned above, digital modulation technology has high spectral efficiency. Although DMB adopts QPSK modulation to solve the problem of mobile reception, its spectrum efficiency is 2bit/Hz.s, and 6 sets of high-quality audio programs are simultaneously transmitted on the RF channel of 1.5MHz, so that 4 DMB channels and 24 sets of programs can be conveniently arranged within the 8MHz bandwidth of a TV channel. This is of course unimaginable under the current simulation system.

In addition, another important feature is that it is convenient to set up a single-frequency network. Using this technology, the same content can be covered in a large area, even in the whole province and the whole country. In fact, it also greatly saves frequency resources and improves the frequency reuse rate, so that the spectrum efficiency will be more prominent.

In addition to the above, DMB also has the characteristics of anti-multipath interference, fast fading, strong mobile receiving ability and high data transmission ability.