China's 5G breakthrough in wireless transmission core technology

The National 863 Program has launched and implemented the 5G mobile communication system advanced research major project (hereinafter referred to as the 5G major project), and has made five important phased progress, and has made breakthroughs
in technology, architecture and other aspects.

The main technical objectives of the first phase of the 5G major project include: research on key technologies such as 5G network system architecture, wireless networking, wireless transmission, new antennas and radio frequencies, and new spectrum development and utilization, complete performance evaluation and prototype system design, carry out wireless transmission technology tests, support the total service rate of 10Gbps, and improve the spectrum efficiency and power efficiency of the air interface by 10 times
compared with 4G.

The second phase of the 5G major project focuses on the following key 5G technologies: the development of a 5G base station soft test platform that can be flexibly configured and has a throughput rate of 10-100Gbps; Explore the development and utilization of millimeter-wave spectrum resources; Research on wireless network virtualization technology in different institutional environments; Explore new mechanisms for 5G network security; Research on new modulation coding technologies for 5G to improve link performance
.
5G is a new generation of mobile communication system
for the development of mobile communication in 2020.

At present, the project has made the following important phased progress:

First, the 5G system requirements and vision, typical application scenarios and KPIs, and spectrum demand analysis research have been completed, laying a technical foundation
for China's participation in the formulation of 5G standards.

The research group completed the research on 5G vision and requirements, proposed 5G typical scenarios and key capability index systems, and input the core research results to the ITU.
The technical evolution route of 5G and the core key technologies of 5G are clarified, and the 5G wireless technology framework and network framework are proposed.
Complete the 5G spectrum demand forecast for 2020, put forward suggestions for potential candidate frequency bands for 5G in China, and carry out channel measurement and modeling research on key candidate frequency bands from 6 to 100GHz.
Effectively organize and carry out 5G research and international cooperation, and gradually form China's leading position
in 5G research.

Second, we will innovate in the research of 5G new wireless network architecture, and make important breakthroughs
in the research directions of wireless network dense networking, high-throughput collaborative networking, CU separation ultra-cellular architecture, and wireless access network virtualization.

The collaborative 2.
0 network architecture, which supports high-density aggregation, is proposed, and the interface design between the software-defined access network and the core network is completed, which realizes the flexible configuration and unified management of high-density aggregation heterogeneous networks.
The system-level simulation evaluation method supporting 5G high-density aggregation heterogeneous network networking scenarios is studied, and a system-level simulation platform is developed.
An indoor test environment supporting high-density heterogeneous convergence of 5G networks has been built, the prototype system design has been completed, and some key technologies have been tested and verified
.

Research on high-throughput 5G wireless network architecture and related key technologies was carried out, including high-density network layering model and frequency multiplexing mechanism, data and control separation architecture, distributed interference coordination and heterogeneous resource joint allocation, wireless self-transmission, self-organizing networking, and unified bearer technology.
The design of the simulation platform of 5G high-throughput wireless network architecture was preliminarily completed.
A proof-of-concept platform for 5G high-throughput wireless network architecture was preliminarily built, and the basic functions
of data plane and control plane separation were realized.

Research on virtualization technology for 5G-oriented wireless networking and access network processing has been carried out, and a complete 5G ultracellular network architecture
has been formed.
The ultra-cellular wireless networking system was designed, and the YaRAN access network infrastructure virtualization platform
was developed.
A non-stack protocol virtualization network architecture, cloud-based radio access network architecture, semi-static infrastructure orchestration mechanism and two-layer resource mapping method, and an LTE and WiFi converged network architecture based on network function virtualization are proposed, which reduces the signaling overhead and service response time of heterogeneous networks.
A 5G ultracellular wireless networking simulation platform and four prototype verification systems were developed, and the above key technologies were verified
.
A unified large-scale prototype verification test bed is being formed to verify the overall performance indicators of the mission, including the domain efficiency, spectral efficiency, energy efficiency and resiliency of the 5G network
.

The 5G wireless converged network virtualization system architecture model, control signaling and service bearer separation technology, protocol stack function virtual division method, multi-heterogeneous wireless communication resource virtualization model, and multi-domain resource cognitive collaboration technology are proposed.
The design scheme of the 5G wireless network virtualization test system is completed, the 5G wireless network virtualization software and hardware test system and simulation platform are preliminarily built, and the theoretical analysis and numerical simulation results show that the proposed signaling simplification scheme can reduce the signaling overhead
compared with the 4G system.

Third, break through the core key technologies of 5G wireless transmission, make important progress in large-scale wireless antenna arrays and efficient collaborative transmission, and lay a solid foundation
for achieving the overall goals of the project.

The research on key technologies of large-scale collaborative transmission suitable for 5G requirements was carried out, and the design and development of channel modeling and channel state information acquisition, spatial division multiple access transmission, link adaptive transmission, high-performance receivers under interference channels, multi-user scheduling, system synchronization and control information transmission, and large-scale MIMO array antennas, compact multi-antennas, and low-power configurable RF technologies were completed for massive MIMO and dense distributed wireless transmission systems.
The construction of the simulation verification platform was preliminarily completed, and the performance and evaluation of key technologies were carried out.
The construction and key technologies of prototype systems supporting 64-antenna massive MIMO and 128-antenna dense distributed wireless transmission were studied
.

The research on the basic theory of high energy efficiency and spectral efficiency of large-scale collaborative transmission, channel modeling, transmission technology, efficient collaborative transmission, energy-saving transmission technology, and the design and development of large-scale active array antenna have been carried out.
The development of link and system simulation platform based on large-scale measured 3D-MIMO was completed, and the performance evaluation and verification of key technologies were carried out.
Software and hardware development and experimental verification tasks
supporting large-scale 128-antenna MIMO arrays, base station processing pools, and terminal experimental platforms have been carried out.

The research on PDMA transmitter and low-complexity receiver, low-latency multivariate LDPC coding and joint coding modulation, iterative channel estimation method for FBMC multicarrier system and low-complexity detection algorithm for super-Nyquist precoding was completed, and the overall technical scheme
of 5G spectral efficiency improvement represented by "PDMA non-orthogonal multi-access + multivariate LDPC coding" was formed 。 Form a non-orthogonal transmission technology scheme for 5G mobile communication; The SCMA transmission simulation verification in the typical scenario of high-density user access was completed.
The simulation verification of NB-LDPC coding for frequent interaction of small traffic packets was completed.
The FBMC transmission experimental verification platform under the typical scenario of "collaborative multipoint transmission CoMP" of 5G mobile communication was built, and some tests and verifications
were carried out.

A massive MIMO complete transmission scheme based on beamdivision multiple access (BDMA) is proposed.
The development of baseband subsystem and fixed-band RF unit has been completed, and the system can support 64-256 antenna channels and build a 5G massive MIMO field test environment; Antenna size, system bandwidth, and processing power are scalable
.

Fourth, break through the key technology of millimeter-wave RF chips that limit the future development of China's industry, and verify the feasibility of physical layer security technology in the application of
5G mobile communication systems for the first time in the world.

Completed the research of millimeter wave wireless access architecture, key technologies of physical layer, and media access control technology; Completed the design and tape-out of millimeter wave CMOS 60GHz RF single-channel system-on-chip and 42-48GHz chip module; The design and implementation of the 60GHz band analog front-end hardware based on the self-developed chip has been completed, so that China's research in this weak link has rapidly approached the international advanced level
.
Facing the formulation of the IEEE 802.
11aj wireless LAN protocol standard led by China, breakthroughs have been made in 45GHz millimeter wave MIMO design, modulation and demodulation, channel compilation and coding, etc.
, and a series of proposals have been submitted to the IEEE International Standards Organization and the draft IEEE 802.
11aj technical standard has been completed
.

The future broadband wireless access security architecture and network security model are proposed, and the feasibility of wireless transmission technology, key generation technology, lightweight encryption and wireless security authentication technology for 5G physical layer security is verified.
Build one set of large-scale antenna experimental verification system, including 2 sets of 32-antenna communication systems that simulate base stations, and 2 sets of 32-antenna communication systems that simulate legitimate users and eavesdroppers, and complete the functional verification and performance self-testing
of physical layer security transmission technology.

A multi-level security architecture that supports multiple business needs, an "unconditional" secure transmission scheme based on physical layer and a cross-layer secure transmission scheme, a new access authentication method based on physical layer and a key distribution scheme based on MIMO are proposed.
Developed a platform that supports 5G wireless access secure transmission and networking simulation; A test environment has been built to support the verification of key technologies such as 5G secure transmission and certification, including two nodes with 8 transmissions and 8 receives, 1 4 sends and 4 receives, and 2 nodes with 2 transmissions and 2
receives.

Fifth, the advanced deployment of 5G new technology testing and evaluation research, support China's 5G technology research and development in the forefront of the world
.

According to the overall 5G objectives, business needs and technical requirements of the test requirements analysis, the test requirements analysis report, the decomposition and definition of the evaluation test system indicators were completed, and the evaluation index set was preliminarily formed.
The user and service distribution model modeling in typical application scenarios has been completed.
Complete the research on system and simulation evaluation methods for 5G networks; The MIMO near-field test scheme was proposed, and a large-scale array antenna software simulation evaluation platform and a large-scale array antenna test environment were built.
Developed a 5G candidate band coexistence evaluation simulation test platform and completed the evaluation analysis.
Preliminary completion of the construction of the field test environment, including the design of test terminals and interference equipment and the development of basic modules; Complete the multi-core parallel computing simulation platform, which supports the simulation
of large-scale antennas and ultra-dense networking technologies.

According to the overall deployment of the Ministry of Industry and Information Technology, China's 5G basic R&D test will be carried out from 2016 to 2018, which is divided into three stages: 5G key technology test, 5G technology solution verification and 5G system verification
.
After that, it will enter the 5G network construction stage, and is expected to be officially commercialized
as early as 2020.

Industry insiders pointed out that in the early stage of global 5G research and development, all links of China's industrial chain, especially enterprises in vertical segments, should actively intervene to jointly promote 5G technical standard research, and through 5G standards and industry research, breakthroughs can be made in core devices and get rid of the situation of external dependence of core devices
.
Ensure that China's industry occupies an important position
in the future 5G standard system.