"The higher the frequency band, the more it will increase the cost of network coverage, and the technical requirements for system equipment and terminals are also higher." On October 15, Shu Huaying, a professor at Beijing University of Posts and Telecommunications, said in an interview with reporters that the 2.6GHz band will be used TD-LTE is no choice, "700MHz is better, but broadcasting is in use."
On October 14, the relevant person in charge of the Ministry of Industry and Information Technology disclosed at the "2012 World Telecommunication Exhibition" meeting held in Dubai, UAE that the Chinese government has clearly divided the 2.6GHz band (2500-2690MHz) to a total of 190MHz using TDD .
This is the first time China has disclosed the TDD spectrum planning plan, which means that China has taken an important step towards quasi 4G TD-LTE operation.
Chang Gang, Chief Marketing Officer of Ericsson China, told reporters that the confirmation of TD-LTE spectrum is of great significance to the development of the entire industry chain, and system and terminal manufacturers can make more targeted preparations accordingly.
At present, China has no clear 4G licensing schedule. Miao Wei, Minister of the Ministry of Industry and Information Technology, said in September this year that "TD-LTE licenses will be issued in about a year's time." When the relevant person in charge of the Ministry of Industry and Information Technology disclosed the 2.6GHz band for TDD, it was not clear which operator or operators would undertake TD-LTE operation in the future.
The industry generally believes that China Mobile, which undertakes TD-SCDMA operations in the 3G era, will choose TD-LTE technology in the 4G era. In the first half of this year, China Mobile has completed the scale test of TD-LTE, and launched the first TD-LTE bidding in August this year. The project contains 20,000 base stations, about 52,000 fans, and purchased TD-LTE equipment. It will be used to expand the TD-LTE scale experimental network in 13 cities including Beijing, Shanghai, Hangzhou, Nanjing, Guangzhou, Shenzhen, Xiamen, Qingdao, Tianjin, Shenyang, Ningbo, Chengdu and Fuzhou. Ten manufacturers including ZTE, Huawei, Ericsson and Nokia Siemens participated in the bidding.
Considering that the TD-LTE frequency band resources planned by the Ministry of Industry and Information Technology up to 190MHz, some brokers analyzed that in addition to China Mobile will clearly build a TD-LTE network, another operator may get a TD-LTE license in the future.
As the WCDMA network currently operated by China Unicom can be smoothly upgraded to LTE-FDD in the 4G era, if there is more than one TD-LTE operator in China in the future, it is likely to be China Telecom. But whether China Telecom chooses TDD or FDD on 4G is currently inconclusive.
Shu Huaying told reporters that from the perspective of spectrum, the 2.6GHz frequency band already belongs to the microwave frequency band, and microwave communication is a line-of-sight line-of-sight communication method due to its high frequency and short wavelength. It will be reflected or blocked when it encounters blocking. This loss will increase the cost of future network coverage for operators, and the technical requirements for equipment manufacturers and mobile phone terminal manufacturers will also increase.
Chang Gang also said that compared with the low frequency band (such as the 700MHz band constructed by the US LTE), building a network on 2.5G-2.6GHz will face more challenges in network coverage.
However, Shu Huaying believes that because the radio and television departments and the military have used certain frequency bands, plus 2G, 3G and other emergency communications occupied frequency bands, from the perspective of the Ministry of Industry and Information Technology, "in a row, only the 2.6GHz band can be used" .
At present, China's 2G is distributed at 900MHz and 1800MHz, the 3G frequency band is at 2100MHz, and the 700MHz frequency band belongs to the radio and television department.
However, Chang Gang believes that the construction of the network not only considers coverage, but also cannot simply compare the differences brought by coverage, but also the capacity factor; in addition, the frequency band currently planned by the Ministry of Industry and Information Technology for TD-LTE includes the TD used by some international operators -LTE frequency band is conducive to global TD-LTE roaming. From an international perspective, the main distribution of TD-LTE frequency bands is concentrated in 2.5G-2.6GHz (such as Softbank in Japan, Sweden 3, Clearwire in the United States) and 2.3GHz (such as NBN in Australia, STC in Saudi Arabia), and also distributed in 3.5GHz (Such as UK Broadband in the UK).
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