TD Technology TD-SCDMA - Time Division-Synchronous Code Division Multiple Access (Time Division Synchronous Code Division Multiple Access). TD-SCDMA  As China&#39;s third generation mobile communication standard  (referred to as 3G), since 1999, officially ITU (ITU) has been submitted, the time has gone through 10 next year, to complete a standard group of experts assessment, ITU approved and published, with the 3GPP (Third Generation Partnership Project) system integration, introduction of new technology features a series of international standardization, so that TD-SCDMA  standard to be the first made by China to China&#39;s intellectual property-based, been widely accepted and recognized international standard for wireless communications. This is an important milestone in the history of China Telecom. (Note: 3G total of 4 international standard, while three are United States-led CDMA2000, WiMAX and European-led WCDMA.) Summary of TD-SCDMA technology Time Division - Synchronous Code Division Multiple Access (English: Time Division - Synchronous Code Division Multiple Access, abbreviated as: TD-SCDMA), are three 3G standards approved by ITU in a, relative to the other two main 3G standards ( CDMA2000) or (WCDMA) to its late start. The standard is defined in the 3G standard. June 29, 1999, China&#39;s former Ministry of Posts and Telecommunications Science and Technology Research Institute (now the Datang Telecom Technology Co., Ltd.) presented to the ITU standard. The standard will be smart antenna, synchronous CDMA, and Software Defined Radio (SDR) technologies into it. In addition, because China&#39;s huge telecommunications market, the standard by all the major telecom equipment manufacturers attention more than half of the world can produce equipment manufacturers have announced support for TD-SCDMA standard telecommunications equipment. TD-SCDMA in spectrum efficiency, support business flexibility, cost, frequency flexibility and unique advantages. As a result of TD-SCDMA Time Division Duplex, uplink and downlink channel characteristics consistent, therefore, the base station received signal is estimated according to the uplink and downlink channel characteristics easier. In addition, TD-SCDMA smart antenna technology has inherent advantages, while the use of smart antenna technology has the advantages of the introduction of the SDMA can reduce interference between users, thereby enhancing the efficiency of spectrum. TD-SCDMA also has the advantages of TDMA, the flexibility to set the ratio of uplink and downlink time slot to adjust the uplink and downlink data rate ratio, especially for a small Internet business in the upstream and downstream data and more occasions. But the upstream and downstream of the conversion point to the same frequency variability increased network complexity of some. TD-SCDMA is a TDD, no pair of bands. Therefore, and the other two Frequency Division Duplex for 3G standard than in the frequency division of resources more flexible. Generally believed that, TD-SCDMA as smart antennas and synchronous CDMA technology adoption, we can greatly simplify the complexity of the system, suitable for software radio technology, therefore, is expected to lower equipment costs. However, due to the shortcomings of their own TDD system, TD-SCDMA is considered the terminal to allow speed and cell radius coverage lags behind the body of Frequency Division Duplex System. Meanwhile, TD only 500 people online, is a problem. ?TD-SCDMA network trials and commercial profile In 2006, Romania established a TD-SCDMA trial network. In 2007, Korea&#39;s largest mobile operator, SK Telecom in Seoul built TD-SCDMA trial network. In the same year, Europe&#39;s second largest telecommunications operator France Telecom established a TD-SCDMA trial network. October 2007, the Japanese telecom operator IP Mobile was originally planned to build and operate the TD-SCDMA network, the company is limited by funding difficulties and ultimately bankruptcy. January 2008, China Mobile in Beijing, Shanghai, Tianjin, Shenyang, Guangzhou, Shenzhen, Xiamen, Qinhuangdao City, built TD-SCDMA trial network; China Telecom in Baoding, China built TD-SCDMA trial network; original China Network Communications Group Corporation (now the China Unicom Group) in China Qingdao built TD-SCDMA trial network. April 1, 2008, China Mobile in Beijing, Shanghai, Tianjin, Shenyang, Qingdao, Guangzhou, Shenzhen, Xiamen, Baoding, Qinhuangdao, and in 10 cities start TD-SCDMA socialization business test and test business. By 2008 end, used in China&#39;s 3G TD-SCDMA network has reached 41.9 million mobile phone users. However, TD-SCDMA mobile phones to distribute telephone numbers on the first day that there are many problems, such as network construction has not yet perfect, not all development and other functions, so many cell phone users are still on the fence. September 2008, China Putian Information Industry Group Corporation, a telecommunications company in Italy MYWAVE built TD-SCDMA trial network, the network on Sept. 12 built and opened; only 11 days from the projected construction projects should be for small businesses net. January 7, 2009, the Chinese government officially issued to China Mobile TD-SCDMA business operating license, China Mobile has started in China&#39;s 28 municipalities, provincial capitals and cities with independent planning for the second phase of TD-SCDMA network construction expected to be completed in June 2009 and put into commercial operation. The company plans to 2011, TD-SCDMA network to cover 100% of the Chinese mainland cities. The development of TD-SCDMA in early 1998, the Ministry of Science and Technology Department of Posts and Telecommunications was under the direct leadership, the Academy of Telecommunications Technology Organization teams based on SCDMA technology, research and drafting of compliance requirements of IMT-2000 TD-SCDMA in China draft recommendations. The draft standard smart antenna, synchronous CDMA, relay switch, the main features of TDD, the ITU IMT-2000 third generation of collecting mobile wireless technology candidate for the program deadline June 30, 1998 submitted to the ITU , making the 15 IMT-2000 candidate for one of the options. ITU comprehensive assessment of the results of the assessment group, in November 1999 Helsinki ITU-RTG8 / 1 meeting, on 18 and in May 2000 in Istanbul, ITU-R plenary session, TD-SCDMA has been formally accepted as CDMATDD formats one of the options. CWTS (China Wireless Telecommunication Standards group) as a regional standards organization on behalf of China, from May 1999 to join 3GPP and after 4 months of preparation, and with 3GPPPCG (Project Coordination Unit), TSG (Technical Specification Group) for a lot of coordination work, in the same year in September proposed to 3GPP 3GPP TD-SCDMA standards into the work of the content. In December 1999 in Nice, France, the 3GPP meeting, our proposal is 3GPPTSGRAN (Radio Access Network) accepted by the plenary session, to formalize the TD-SCDMA into Release 2000 (after the split for the R4 and R5) of the work plan, TD-SCDMA will be referred to as LCRTDD (low chip rate TDD scheme). After more than a year, went through dozens of working group meetings to discuss the draft of hundreds of articles submitted, Palm Springs in March 2001 the RAN plenary session, with the TD-SCDMA standard contains 3GPPR4 version of the specification, including the formal release, TD-SCDMA in the integration of work in 3GPP to achieve the first goal. Thus, TD-SCDMA, whether in form or in substance, have been large in the international operators, equipment manufacturers have recognized and accepted to form a truly international standard. ?The status of TD-SCDMA standard Since March 2001 3GPPR4 release, TD-SCDMA standard specifications in the 3GPP system, the main substantive work accomplished. R4 standard distribution in more than two years after the time, Tang and other operators of many of the industry providers, equipment manufacturers in together, and after another meeting to discuss numerous times, mailing list discussions, Tongguotijiao the Daliang presentation, on the TD-SCDMA standard Guifan The physical layer processing, high-level protocol stack information, network and interface signaling messages, radio frequency indicators and parameters, compliance testing and other parts of the contents of a meeting of the revision and improvement of the TD-SCDMAR4 so far achieved a considerable standard stability and maturity level. Within the framework of the 3GPP system, through integration of sound, due to differences in duplex mode, TD-SCDMA technical features and advantages of all able to reflect the physical layer air interface. The difference between the physical layer technology TD-SCDMA and WCDMA is the most important difference lies. In the core network side, TD-SCDMA and WCDMA use exactly the same standards, including core network and radio access network using the same between the Iu interface; in the air interface protocol stack on top, TD-SCDMA and WCDMA both have exactly the same . These similarities between the two systems to ensure a seamless roaming, handover, operational support consistency, QoS guarantees, etc., but also to ensure the TD-SCDMA and WCDMA technologies in the standard follow-up development to maintain a fairly consistent. January 20, 2006 has been declared China&#39;s national communications standards. (Note: is inexact. January 20 Ministry of Information Industry provides the industry standard, rather than the country&#39;s communications standards) ?TD-SCDMA standard follow-up development In 3G technologies and systems flourish, whether the various equipment manufacturers, operators, or the various research institutions, Governments, ITU, have already begun the development of 3G technology directions of future research. Identified in the ITU in the development of several technologies, including smart antenna technology and TDD Time Division Duplex technology, that these two technologies are the future trends in technology development, and smart antennas and TDD Time Division Duplex these two technologies, in The current system of TD-SCDMA standard has been a very good reflection and application, from that point, also be able to see the technology TD-SCDMA standard are quite promising. In addition, 3GPP R4 version after the release, TD-SCDMA standard are also different degrees introduces new technical features, to further improve the performance of the system, which mainly include: the air interface between base station synchronization, as a base station Another backup synchronization programs, especially for emergency situations for communication network reliability guarantees; terminal positioning function can be smart antennas, using the signal arrival angle of the end-user location positioning, in order to better provide location-based services; High-Speed Downlink Packet Access, a hybrid automatic repeat, adaptive modulation and coding to achieve high-speed downlink packet service; multi-antenna input-output technology (MIMO), using the base station and terminal multi-antenna technology and signal processing to improve wireless system performance; uplink enhancement technology, adaptive modulation and coding, hybrid ARQ technology, dedicated / shared resources and the rapid distribution of the corresponding physical layer and high-level support mechanism for signaling, enhanced upstream channel and operational capacity. The government and the full support of operators, TD-SCDMA Industry Alliance and the industry chain has been basically established, product development has also been further enhanced, more and more equipment manufacturers have invested in TD-SCDMA product development camp in the past. With the device development, field tests on a large scale, TD-SCDMA standard will also be further verified and strengthened. TD-SCDMA in order to speed up the industrialization process, to form a complete industry supply chain and multi-vendor environment, October 30, 2002, TD-SCDMA Industry Alliance in Beijing. TD-SCDMA Industry Alliance member companies from the original seven, to the current 30 companies, covering the TD-SCDMA industry chain from the system, chip, terminal to test various aspects of instrument. Union Properties: TD-SCDMA Industry Alliance is actively engaged in the cause of TD-SCDMA, TD-SCDMA 标准 从事 and products Yanjiu, 开发, production, manufacturing, services of enterprises, institutions Ziyuanzucheng the Shekuaituanti. Union Mission: Integration and coordination of industry resources to improve the Union of the mobile communication research and development, production levels, and promote TD-SCDMA communication industry, rapid and healthy development, to achieve TD-SCDMA in China and the global communications market promotion and application. Union business: TD-SCDMA Industry Alliance, the main focus on TD-SCDMA technology standard and the industry to promote and improve the management and coordination, promote resource sharing among enterprises and mutual benefit, suggest that the development is conducive to the development of TD-SCDMA a major industrial policy to enhance the Union communications business group competitiveness. TD-SCDMA Industry Alliance, intellectual property management within the implementation of a unified policy, technical information and market information to a high degree of sharing, through close communication and reasonable division of labor, TD-SCDMA industry to promote rapid and healthy development. Coalition members: Academy of Telecommunications Technology (Datang Telecom Technology &amp; Industry Group) Hualijituan Co., Ltd. Huawei Technologies Co., Ltd. Lenovo (Beijing) Co., Ltd. Shenzhen Zhongxing Telecom Co., Ltd. China Electronics Corporation China Putian Information Industry Group Corporation Beijing chipset and solution Co., Ltd. Beijing Rising Technology Co., Ltd. Co., Ltd. Chongqing CYIT Hisense Group Co., Ltd. COMMIT Information Technology Co., Ltd. Xi&#39;an Haitian Antenna Technology Co., Ltd. Spreadtrum Communications (Shanghai) Co., Ltd. Measurement Science and Technology of Beijing Co., Ltd. Chong letter Friends of Science and Technology Industrial Co., Ltd. Hubei public Alcatel Shanghai Bell Co., Ltd. Shanghai DBTEL Industrial Co., Ltd. UT Starcom Inc. Inventec Appliances (Shanghai) Electronics Co., Ltd. Zhongshan Tongyu Communication Equipment Co., Ltd. Qingdao Haier Telecom Co., Ltd. The Haike Tai Century Technology Co., Ltd. Wuhan Research Institute of Posts and Telecommunications TCL Group Guangzhou City Post Communications Equipment Co., Ltd. Andrew Telecommunication Equipment (China) Co., Ltd. Comlent Communications (Shanghai) Co., Ltd. Beijing Xing Communication Software Co., Ltd. Highlights Comba Telecom Technology (Guangzhou) Co., Ltd. 14th Institute of China Electronics Technology Group Corporation Mount Antenna Technologies (Shenzhen) Co., Ltd. RDA Microelectronics (Shanghai) Co., Ltd. Beijing Ming Han Technology Co., Ltd. ICT Ningbo Bird Co., Ltd. 41st China Electronics Technology Group Corporation Institute BOCO Inc. Network Technology Co., Ltd. Shenzhen Mayor Square Yulong Computer Telecommunication Technologies (Shenzhen) Co., Ltd. Simcom Information Technology (Shanghai) Co., Ltd. Longcheer Holdings Limited. ?China&#39;s TD with the United States, Ouqie for technology&#39;s advantages and disadvantages Advantage 1. TD a high spectrum efficiency of a carrier frequency of the carrier frequency 1.6MW 10M 2. On the power control requirements of low TD 0 ~ 200MZ W 1500MZ 3. With the introduction of smart antenna and joint testing of the so-called air classification, but the effects are still to be verified 4. To avoid the effects of TD respiratory different business impact on the coverage area the size of the small, easy-to-network planning 5. To support a variety of communication interfaces: TD-SCDMA meet Iub, A, Gb, Iu, IuR a variety of interface requirements, base station subsystems for 2G and 2.5G both the GSM base station of the expansion, but also as a 3G Network base station subsystem, can also take into account the needs of present and future long-term development. Disadvantages: 1. Simultaneous need for high TD GPS synchronization, synchronization accuracy affects the whole system is working 2. Yd TD limited resources only 16 yards, far less than the business requirements of the code required number of 3. Downlink interference, the cell, adjacent cell interference may exist 4. Moving slowly TD 120KM / H W 500KM / H ?TD-SCDMA socialization business test and trial commercial March 28, 2008 message, the mobile media meet will be held today formally announced on April 1, the construction of eight in their official launch of the Olympic city of China-made 3G (ie TD-SCDMA) of social services testing and test business, specifically including Beijing, Tianjin, Shanghai, Qingdao, Qinhuangdao, Shenyang, Shenzhen and Guangzhou eight cities. China Mobile said that during the trial commercial mobile phone homemade 3G basic monthly fee is 50 yuan / month, local basic phone calls calling four corner / called free; domestic long distance call charges 0.07 yuan / 6 seconds. During the trial the commercial discount cost 5 It is understood that this test for the uniform application of business phones in paragraph 157, not the previous rumors of 159 paragraphs, will be invited to move the first batch of 20 000 different trades and sectors representative of a certain end-users to participate in domestic 3G network , the full range of testing services, free of charge 2,000 yuan to 4,000 yuan worth of test phones and data cards, each providing 800 test users prognosis, subsidies, and commercial users to test 3 TD preferential packages and data card set, voice tariff rates below the current G network. China Mobile said that during the trial commercial users in the network communication cost incurred TD enjoy 5 fold, in the first procurement of mobile terminals 100-200 dollars than purchasing the lowest sales in the operating room, to channel some benefits of social cooperation, TD Fang Hao remuneration 2 times higher than GSM, and has additional sales incentive. April 1, the user can 移动营业厅 in 8 cities and some co-channel cards can be purchased TD vanguard, uniform price 20 yuan / piece. Specific charges for basic monthly fee is 50 yuan / month, local basic phone calls calling 4 Corner / called free; domestic long distance call charges 0.07 yuan / 6 seconds. Video calls Caller 0.6 yuan / minute, called free, long-distance calls 0.1 yuan / 6 seconds, the domestic video call roaming caller 0.9 yuan / minute, called 0.6 yuan / minute. In addition, China Mobile ready for 28 yuan, 58 yuan and 88 yuan 3 TD tariff packages, which package includes 150 minutes to 28 yuan video calls, caller ID, the Olympic and 10M T-Mobile reported net flows; 58 yuan package includes 350 minutes Video Phone, Caller ID, Olympic mobile phone newspaper, 10M T-net traffic as well as ring tones; and 88 packages containing 600 minutes video calling and caller ID, cell phone reported that the Olympic Games, 10M T-net traffic as well as ring tones. TD broadband data access, including 100 and 200 are two packages, which contain 100 packages 2G flow 200 contains 5G traffic, beyond the flow of 0.01 yuan / k, non-package users 0.03 yuan / k, also cap the monthly data traffic 1000 Yuan, also 5 discount for communication costs do not include the letter G Netcom fee. 8 City Unified distribute telephone numbers starting 60000 Terminal According to China Mobile to introduce, in this commercial city to test-8, rather than expand the test network 10. First half of last year, TD test expanded to 10 cities, in addition to China Mobile after the construction of Beijing, Tianjin, Shanghai, Xiamen, Qinhuangdao, Shenyang, but also additional Guangzhou and Shenzhen, in addition to Qingdao, China Netcom primarily conducted by the test, while China Telecom in Baoding from the main test. The source said the reunification of China Mobile to distribute telephone numbers is 8 instead of 10 cities, Qingdao and Baoding, China Netcom and the specific arrangements will depend on the specific arrangements for telecommunications. It is reported that a total of 11 handset manufacturers have access to network license, China Mobile currently Jicai of 50,000 from the first batch of TD mobile phone network license access to vendors, including ZTE, Samsung, LG, Hisense, Lenovo, New Post-pass; another move was also collected from Datang Mobile TD on 10 000 network card. China Mobile said that 60 000 TD terminals will be in its eight Olympic Games cities in their own operating room to distribute telephone numbers, but companies can also sell their own sales channels outside Jicai TD terminal. In two recent period, China Mobile president Wang promised TD catch in the commercial during the Olympics, recently said in an interview in April will enter the TD commercial trial. Moving an insider confirmed to Artesyn Technologies, &quot;TD distribute telephone numbers ready, just waiting for the Group to distribute telephone numbers to determine the specific date.&quot; He also explained that &quot;because the terminal in place of the problems leading to delays date to distribute telephone numbers. &quot; April 1, 2008 start from the TD commercial trial of Mobile Telephone Number Service. The history of the Chinese 3G TD Fang Hao another milestone, marking the national 3G standard TD has been completely equipped with basic business operations. The test section of 157 commercial from the Olympics there four and a half months, have more time to network optimization, system management and system improvement charges, etc., in the future presented to us during the Olympic Games will be a new The introduction of 3G standards. Bypassing the 3G mobile licenses in the first TD of the Unicom launched a major blow. As the restructuring and 3G licensing situation of uncertainty, within the next 3-6 months are not immediately Unicom launched 3G services, short-term users can experience only in the movement of TD, for future 3G services to launch first-mover advantage, and will affect data cards to China Unicom&#39;s advantage, the future will not rule out the occurrence of more serious churn. However, the domestic telecom equipment suppliers, the TD will be a major positive gate. Once the TD has not released it means to open the bow back arrow, TD will also be necessary investment to accelerate the trend. We are optimistic about the future more reason such as ZTE and Datang Telecom Equipment ST listed company&#39;s development prospects. ?TD-SCDMA wireless Internet access (TD Wireless Internet) Currently available in the following cities use 3G/TD-SCDMA wireless Internet network: Beijing, Shanghai, Tianjin, Shenyang, Guangzhou, Shenzhen, Xiamen, Baoding, Qingdao and Qinhuangdao 10 cities, in the absence of TD-SCDMA network will be automatically converted to cases GPRS wireless network. Beijing Wuhuanyinei a TD signal, can cover to the outer rings 1-5km, rings other than the location of large residential communities and counties (on the ground, Huilongguan, etc., county, etc.) are covered. Shanghai outer ring within a TD-SCDMA signals. The main city of Tianjin, Guangzhou City has a TD in most other coverage. Good signal in the case of TD the actual download speed wireless Internet access in the 30-60K / S, which translates to 512K ADSL broadband speed. Currently China&#39;s TD Mobile wireless Internet business focused on development. ?TD-SCDMA netbook (TD mini-computer) At present, China Mobile has issued various well-known computer makers that can be customized to support TD-SCDMA wireless mini-computer network (the Internet this), TD Internet belong to the lower end PC makers launched products, including low cost and energy efficient x86 and the ARM processor is the Internet of the fundamental, while the Internet access of the implant of the TD module, eliminating the cost of higher prices of data cards, with China Mobile for future TD Internet data traffic costs of the subsidies, the total costs and will not be very high. TD Internet the screen size from 7 to 10.2 inches or so. ?China Mobile TD-SCDMA Official Website China Mobile TD-SCDMA socialization business test and trial the only official business website, the only officially open to the public domain name: tdtest.chinamobile.com ?