【Focus on TD】Four lessons left by TD-SCDMA

December 12, 2014 at 16:02T

It is impractical to develop international communication standards by a single country; Lack of awareness of TD technical deficiencies; Industrial policies should be used with caution; Respecting economic laws is the right way to promote China's telecommunications industry to the world. Pen & Fun & Pavilion www.biquge.info

Qiu Shi|text

Since the beginning of reform and opening up, China's progress and achievements in all aspects are obvious to all. At the same time, we also paid a lot of tuition fees in the process of moving from a planned economy to a market economy. One example is TD-SCDMA, which has independent intellectual property rights.

One of the lessons learned is that it is not practical to develop international communication standards on the part of a single country.

In 1998, ITU called for 3G proposals, and the Telecommunication Institute wanted to make a difference in 3G standards. This is a correct starting point, but we ignore the situation in China at the time. At that time, China had little foundation and experience in the research and development of mobile communication networks. Huawei and ZTE are only just beginning to get involved in the development of GSM systems and are still in the learning stage. Prior to this, China's telecom companies basically did not send people to participate in international standards conferences, and Chinese companies did not have experience in doing international standards. It should be said that China's telecommunications enterprises did not have the ability to independently develop international mobile communication standards at that time, especially at that time, we were not familiar with or understand the development laws and rules of the game in the international telecommunications industry. It stands to reason that we should make good use of this opportunity to encourage Chinese telecom manufacturers to actively cooperate with other internationally renowned manufacturers and international organizations to learn, improve, develop and grow in the joint development of 3G standards.

At the beginning, China's plan was not recognized by the ITU due to some inherent technical deficiencies. In order to get TD-SCDMA into the 3G standard, the Chinese side used the huge development potential of the Chinese market as a bargaining chip, with the help of the Chinese government, to exert pressure on other telecom equipment manufacturers to force them to accept China's TD-SCDMA as one of the 3G international standards.

One of the after-effects of this is that it pits China's telecom companies against their international counterparts, while also leaving China's 3G standards isolated in the world. In the early stage of the development of the 3G standard, no mobile operator in the world expressed interest in China's 3G standard, and no foreign communication equipment manufacturer planned to develop China's 3G standard communication equipment. In the 3GPP standards conference, the main companies that promoted China's 3G standards were Siemens and Datang, and Huawei and ZTE only started a few years later. Other companies' proposals are mainly based on patent protection considerations, just in case the Chinese government insists on promoting Chinese 3G in China, they have enough patents to exchange with Chinese companies without having to pay additional royalties to enter the Chinese market.

In fact, in the early stage of the development of the 3G standard, all companies were almost on the same starting line. Although Chinese companies have less experience and technical reserves, if the Chinese government can guide Chinese telecommunications companies to cooperate with their international counterparts, realize our gaps, and actively forge ahead and strive to catch up in the research and development of international mainstream 3G technology, Chinese companies' technological reserves in mobile communications will be far from the current level.

Any ITU-endorsed alternative technology for the 3G (IMT-2000) international standard requires a process of redevelopment and re-creation before it becomes a truly international standard that can be used in practice. This standardization process requires a lot of human and material resources from the global telecommunications industry, and it also generates many innovative technologies and patents. In the context of communication globalization, the development of international mainstream technical standards is the result of concentrating the experience, wisdom and financial resources of the global telecommunications industry. So, how can standards developed by a single country compete with them? China is a big country, but it's not a smart move to fight the whole industry. This strategy of confronting the world's mainstream technology has led many Chinese telecom companies to a detour. making it impossible for them to compete with their international counterparts in mainstream technology. It also deprives Chinese telecom companies of the opportunity to prove themselves to the international telecom industry through our technological innovation in the development process of 3G standards.

The second lesson is that TD-SCDMA is not well understood as an international mobile communication standard.

In fact, TD-SCDMA technology is not as advanced as Datang advertises. First of all, TDD stands for Time Division Duplex. Since the invention of mobile communications, frequency division duplex (FDD) has been used in mobile communications. TDD (Time Division Duplex) is only used as a supplement to FDD (Frequency Division Duplex) due to its own limitations. Here's why:

1) TDD spectrum cannot be continuously allocated to different network operators. An isolated bandwidth of 5 MHz must be reserved between two adjacent carriers to avoid mutual interference. This 5MHz bandwidth isolation band is basically unusable, resulting in a decrease in overall spectrum utilization;

2) The uplink and downlink bandwidth of TDD (Time Division Duplex) cannot be flexibly adjusted. If adjustments are required, they must be uniformly adjusted across the entire network. Because the demand for bandwidth in different regions is different at the same time, it loses the meaning of flexible adjustment. TDD systems do not allow different uplink and downlink bandwidths to be used in adjacent communities. Because this will create interference that will prevent communication from proceeding properly;

3) In order to avoid interference, the uplink and downlink time slots of TDD (time division duplex) system need to be accurately aligned, which puts forward stricter requirements for the phase synchronization of the system, which leads to the complex design cost of the system;

4) China's proposal (SCDMA) includes 8-unit smart antenna technology. At that time, the smart antenna technology was not mature, the equipment structure was complex, and there was no precedent for large-scale commercial use. A typical mobile communication base station only needs two wireless transceivers. Datang's solution, on the other hand, requires 8 pairs of wireless transceivers;

5) The 3G communication system is designed for broadband communication, with a bandwidth of 5MHz per channel. Datang's solution is based on a bandwidth of 1.25MHz, which is the same as the bandwidth of the second-generation CDMA mobile communication system, and has a certain gap with the design goal of the 3G system. That is why China's proposal could not be supported by ITU at that time.

In fact, TD-SCDMA technology is not original to Datang. It is based on the research results of Xu Guanghan, a Chinese professor in Texas, USA, and the wireless local ring technology of a Chinese start-up (CWill). TDD (Time Division Duplex) is not used because TDD (Time Division Duplex) has any advantages, but simply because with smart antenna technology, the travel channel estimation must be performed on the same frequency.

The third lesson is that the impact of telecommunications industry policy on the development of the national telecommunications industry is very important, so the policy must be introduced carefully.

There is a precedent in the development of second-generation mobile communication standards for examples of negative impacts on the development of the telecommunications industry due to the wrong direction of the industry. For example, Japan's second-generation mobile communication technology PHS, which is what we call PHS. The main reasons for PHS's success in Japan are:

Consumers in Japan have no other choice but PHS (PHS). PHS can succeed in Japan. However, there is no room for survival in the international market. Japan's decision on the second-generation mobile communication system has led to the fact that Japan's telecommunications manufacturing industry can only develop in Japan, and cannot go abroad into the world. Until now, Japan's telecommunications manufacturing industry has not been able to compete in the international mobile telecommunications market.

China's TD-SCDMA and Japan's PHS (PHS) situation are completely unclear. China has been reformed and opened up, and there are already international mainstream technologies in the telecommunications market. GSM has been widely used in China. Consumers can choose mobile communication technology and operators according to their needs and personal preferences. The market decided that TD-SCDMA could not succeed in China. This is despite the fact that the government has made a big bet and invested huge sums of money. Consumers will not choose China's 3G because of these factors. Unless China recloses the telecom market, only TD-SCDMA technology will be allowed to provide mobile services in the Chinese market, forcing Chinese consumers to have no choice. The result of the market economy is the survival of the fittest, which is the law of the market. If we want to open up the market, we must follow the laws of the market and allow the laws of the market to work.

By the same token, the TDMA (D-AMPS) technology in the United States did not succeed in the end. Although TDMA has been successfully commercialized in the United States, Latin America, South America, and some other regions for more than a decade, it ultimately loses out to GSM and CDMA in terms of economies of scale. Qualcomm's CDMA is the second more successful mobile communication technology in addition to GSM. At one time, it had a 13% share of the global mobile communications market. But in the end, he did not escape the fate of defeat. The market has chosen the mainstream communication technology with the best economies of scale. These examples show that mobile communication is a global market, and a unified global standard is the direction of development. Any attempt to come up with something new will not succeed. This is the law of the market. The United States and Japan were the world's largest and second largest economies at the time. However, due to the detachment from mainstream technology and the violation of the laws of the market, it can only end up now.

The fourth lesson is that respecting economic laws is the right way to promote China's telecommunications industry to the world.

Because we do not have a proper understanding of the development and changes of the international telecommunications market, an inappropriate understanding of the issue of independent intellectual property rights, and the misleading of some people, we have raised a purely technical and market issue to the political level of whether or not we are patriotic. With the promotion of nationalist sentiments, the promotion of the industrialization of TDSCDMA has become a political event under the banner of China's independent intellectual property rights. The hat of not being patriotic and not supporting China's independent intellectual property rights can be put on the heads of those who disagree with TD-SCDMA at any time. It is in such an environment that opposing opinions are suppressed. Proponents of TD-SCDMA are able to promote the "advanced nature" of TDSCDMA regardless of technical and commercial objective facts. The government can also impose TD-SCDMA on the heads of China Mobile and consumers, and invest a large amount of state-owned funds to promote the marketization of TDSCDMA, destroying the balance and regulation of the market economy itself on the industry.

For the average business, it can survive only if it can be profitable. Therefore, most companies will choose a relatively easy way to survive. TD-SCDMA provides these companies with such a good opportunity to survive without having to compete with the strong players in the world telecommunications market. Many telecom companies are rushing to invest their main energy in the product development of TD-SCDMA, and lobbying the government in various ways to continue to promote TD-SCDMA and continue to promote "China's independent intellectual property rights". The resources and capabilities of any enterprise are limited. When most of the resources are invested in non-mainstream technologies, the investment in mainstream technologies will inevitably decrease. This is why it is difficult for most state-owned telecommunications equipment manufacturers to go abroad and lack competitiveness in the international market. Now, in order to get out of its own predicament, China Mobile has strongly promoted the commercial use of TDDLTE, and at the same time stopped continuing to invest in TD-SCDMA. This has indeed caused some troubles to some domestic telecommunications equipment manufacturing companies. Although TD-SCDMA and TDD-LTE both use the non-mainstream TDD method in mobile communication to achieve duplex communication, they are two completely different mobile communication technologies. These companies must re-learn and re-accumulate their experience in technology and product development in TDD-LTE. If Chinese companies continue to take such detours, then when will we really catch up with the world level?

Now that the door to reform and opening up has been opened, we must move forward and integrate with the general trend of international telecommunication development. Don't look back and nostalgia for the market closure and market protection in the era of closing the country, don't let the utilitarian psychology that only cares about immediate interests and does not pay attention to long-term development have room for survival, don't let narrow nationalism affect the development of China's telecommunications industry, and don't let some people with ulterior motives mislead the country's telecommunications development direction for their own interests, so that China will cultivate a group of idealistic, ambitious and competitive enterprises like Huawei.

The world's first commercial 3G mobile network was launched in 2001. China's 3G license was issued in 2009. We are eight years behind Japan. The world's first commercial LTE network was put into commercial use in 2009. China's 4G license was not issued until 2014. We are 5 years behind the United States and Europe. We have waited so many years and spent so much money for TD-SCDMA, what have we learned? Will we keep pace with the international megatrends and mainstream in the direction of telecommunications development in the future? It will depend on how the Chinese government guides, coordinates, and fulfills its regulatory responsibilities. ■

The author is an expert in telecommunications equipment manufacturing

Original

2009