Wednesday, January 5, 2011
College】 【weak digital radio and analog radio difference】.
<br> radios in the design of technology can be divided into analog analog radio communications technology (that is our common traditional walkie-talkie) and the use of digital technology in design of digital radio. .Analog radio signals are stored to the radio transmission frequency modulation, and digital radio sucked voice digital information transmitted in digital code form, that is, all the radio transmission frequency modulation are digital. .<BR> 70s of last century digital technology into Motorola's first wireless radio design in 1975 to produce the encrypted digital radio voice, digital data developed in 1980 to restore the system. .With the development of wireless communication technology, people are required to improve the quality of wireless communications and the increasing lack of spectrum, digital radio will have a huge market demand. .Currently, global demand for digital radio is also increasing, especially in the public safety sector. .However, only the direct use of digital signal processors is the real radio digital radio, and we present a common radio digital control signals (such as the cluster system of the walkie-talkie) does not belong to digital radio category. .<BR> Digital radio has many advantages, above all, make better use of spectrum resources. .And cellular digital technology similar to digital radio channels at a specified load more users and improve the spectrum efficiency, which is a program to solve the frequency congestion, with long-term significance. .Second is to improve call quality. .As digital communications technology has the system error correction, and analog radio than you can in a wider range of the signal environment, for better voice audio quality, which received some of the audio will be less noise, sound, and more .clear. .Finally, to enhance and improve voice and data integration, change control signal decreases with increasing distance communication weaknesses. .And similar to the integrated analog voice and data systems, digital radio can provide better data processing and interface functions, so that more data applications can be integrated into a single structure of two-way wireless communication base stations, voice and data services .better integrated and more convenient. .These three characteristics, which make the development of digital radio to become the inevitable trend of the future radio. .<BR> Analog into the digital premature <BR> domestic production is still based on analog radio walkie-talkie based, domestic radio industry has been concentrated in low-end market, and the clone is serious, so the industry believe that the development of analog towards digital radio ., is an enterprise technology and strength of the test, this process also happens to be a good time to shuffle companies, took the opportunity to eliminate some of the weaker companies. .<BR> Although digital radio market prospects, but the walkie-talkie technology is already very mature analog technology, in a very long period of time will continue to design services for the radio, digital radio will replace analog radio in a short time. ."In the interview, many companies are holding this view, in fact, this view has also been recognized by experts. <BR> U.S. and European markets had done a survey: 2003 digital radio and analog radio ratio is 2:8 ., to become 5:5 in 2004, estimated that by 2007 the ratio will be 8:2. but our relation to other parts of the world's radio market, the gap is very large. So far the digital cluster in addition to .Digital radio use (very few), the professional radio, not only no domestic production, imports of machines did not even appear. Although in recent years as rapid economic development, the use of walkie-talkie rapid development, it is estimated that the annual growth rate is not low .20% of the total, and its market penetration and Europe are very far. at home or in many parts of the world, the first since the solution can be used to buy the issue, then the problem is with a good machine. At present radio .Simulation technology has been very mature, the key device has been very reliable, in terms of call quality and cost-effective from the basic functions of particular point of view, has been completely meet the different industries, different levels of user needs, can adapt to different users of consumer level. <BR .> However, while digital radio is good, but expensive, to other parts of the country or the world (except for outside Europe) to develop new markets to replace the simulator there are many way to go. so it can be said about analog machines in the current phase-out, digital .machine is too early to replace the other issues. As digital trunking unit for command scheduling, government departments, large enterprises use more, less expensive to accept this. The ordinary professional radio except for a few high-end machines, the majority of .walkie-talkie users entirely separate user groups, the lowest volume only acceptable, so whether in China or in many parts of the world, analog radio will continue to occupy a longer period of time most of the market share of radio. Only .When the cost of digital radio down significantly, the technology is also more manufacturers to master all kinds of different grades of digital radio can accept the different user groups when talking about this not too late to come back. out, or to replace .All this will be the final say by walkie-talkie market, is the user the final say..