On March 5 th, a few days ago, the Radio Administration Bureau of the Ministry of Industry and Information Technology issued the announcement of "Radio Frequency Technical Requirements for Base Stations of 5G Mobile Communication Systems in 2100MHz Band (Trial)" (hereinafter referred to as "Trial Announcement").
According to the announcement, in order to meet the demand of 5G applications and ensure the compatibility and coexistence of China’s 2100MHz 5G mobile communication system and other radio services, according to Announcement No.80 of the Ministry of Industry and Information Technology of the People’s Republic of China in 2015 and Notice of RF Technical Requirements for Low and Medium Frequency 5G System Equipment (No.87 [2020] of the Ministry of Industry and Information Technology), the Radio Administration of the Ministry of Industry and Information Technology studied and formulated the Trial Announcement.
The announcement further cleared the way for the co-construction and sharing of China Telecom Unicom’s 5G network. This means that the dual-band 5G strategy previously formulated by China Telecom and China Unicom can be implemented aboveboard, and it also means that both parties can promote the collaborative innovation of the world’s widest TDD(200M) and FDD(2x40M) spectrum, maximize the spectrum benefits and realize.
At present, China has allocated relevant 5G frequency bands to the four major operators. As far as China Telecom and China Unicom are concerned, China Telecom got (n78), which is the 3.5GHz band (); China Unicom also got the 3.5GHz frequency band () on (n78). As can be seen from the allocated frequency bands, the frequency bands allocated by China Telecom and China Unicom on n78 are continuous, which is beneficial for the two companies to jointly build a 5G network.
It should be noted that, unlike the previous mobile communication network standards, the 5G network must cooperate with high, medium and low frequencies according to the user’s service coverage and speed requirements to form efficient and coordinated layered coverage. Wei Leping, executive deputy director of the Science and Technology Committee of the Ministry of Industry and Information Technology and director of the Science and Technology Committee of China Telecom Group, once pointed out that according to the existing distribution scheme, China Telecom and China Unicom only have 100MHz in the 3.5G band, and the uplink coverage of 3.5G band is 9dB and 5dB different from that of 1.8GHz and 2.6 GHz under the premise of the uplink edge rate of 3Mb/s, which leads to the uplink coverage of SA in the 3.5G band, and the uplink capacity and delay are difficult to effectively support vertical industry applications.
"The only way out is to deploy 2.1G/1.8G FDD system as uplink enhancement, cooperate with 3.5G, complement high and low frequencies, and aggregate in time-frequency domain, so as to have the network advantage and economic feasibility of turning to 2B in uplink coverage, uplink capacity, delay characteristics and even investment." Wei Leping said.
China Telecom and China Unicom’s 2.1GHz band have been used in 3G/4G networks for a long time. After the 5G was jointly built and shared, the two sides plowed the frequency band to deploy 5G and increased 5G coverage. It is reported that China Telecom’s 2.1GHz(Band1,n1),1920~1940/
2110~2130MHz was originally approved for deploying CDMA2000, which is 3G band. The actual CDMA2000 uses 825~835/870~880MHz, which is used to deploy LTE FDD.
China Unicom’s 2.1 GHz (Band 1, N1), 1940 ~ 1965/2130 ~ 2155 MHz: originally approved for deploying WCDMA, it is 3G band. Now it is mainly used to deploy LTE FDD, Unicom’s 4G important frequency band and 5G NSA networking anchor frequency band.
In the 2.1GHz band, the spectrum of both China Telecom and China Unicom is continuous, plus the continuous spectrum in the 3.5GHz band. The integration of resource endowments between the two parties has achieved the effect of 1+1>2, and doubled the scale, coverage, bandwidth and speed of the 5G network. It can be said that you naturally have a leading experience at birth.
In the past year, China’s 5G commercialization has taken solid steps. According to public data, by the end of 2020, operators have opened a total of 718,000 5G base stations, and the number of 5G mobile terminal connections has exceeded 200 million. According to the plan, about 700,000 new 5G base stations will be built in China this year.
Faced with the contradiction between huge market space and huge investment in 5G construction in the future, how to build a high-quality 5G network with wide coverage, high speed and good perception with high efficiency and low cost is a difficult problem for operators.
Without any experience to learn from, China Unicom and China Telecom boldly explored and pushed forward with all their efforts. On September 30th last year, they quickly completed the construction and commercialization of the world’s first-scale 5G co-construction and sharing network, and completed the end-to-end capacity deployment of SA independent networking mode.
By October 2020, the scale of 5G sharing between the two sides has reached more than 300,000 stations, covering all cities above prefecture level in China. It has achieved three "world firsts": the world’s first and largest 5G network; The world’s first 200MHz high-bandwidth high-performance 5G network; The world’s first 5G network with TDD+FDD hybrid networking. Through co-construction and sharing, the construction and operation costs of 5G networks will be significantly saved. CAPEX is expected to save about 40%, and OPEX will save about 35% every year, fully highlighting the advantages of co-construction and sharing.
The achievements of co-construction and sharing have laid the foundation for the development of the 5G market. In the next stage, both parties will focus on users and experience to create a high-quality 5G boutique network.
Miao Shouye, head of the working group of China Unicom’s 5G co-construction and sharing, once pointed out that a high-quality 5G boutique network should have three typical characteristics: minimalist network, extreme experience and extreme intelligent service.
"Minimalist network" is a clear minimalist target network to promote future construction, promote network slimming, realize intergenerational decoupling of standards through network resource integration, and let 5G go into battle lightly. Specific objectives include system minimalism, architecture minimalism and site minimalism.
In terms of minimalist standards, China Unicom is currently facing the situation of 2G to 5G four generations living under one roof, which is under great operational pressure. China Unicom hopes to finally form a 4G+5G cooperative minimalist target network.
In terms of minimal architecture, Unicom Telecom’s co-construction and sharing accelerated the evolution of NSA to SA architecture, simplified the complex network structure after the superposition of NSA and co-construction and sharing, and reduced the difficulty of tight coupling optimization of 4G and 5G dual networks; At the same time, SA architecture can support the digital development demands of toB industry. At present, China Unicom has taken the lead in drawing networks and terminals to open SA capabilities in many provinces, fully supporting the development of the toB market.
On the whole, China Telecom and China Unicom’s 3.5G+2.1G dual-band collaborative network construction strategy takes into account competitiveness and investment reduction, but it is still necessary for both the terminal and the network to support 2.1G NR, 2.1G and 3.5G dual-band CA and SUL, so as to ensure the success of the next large-scale commercial deployment of 5G networks.
关于作者