About Purple Mountain Laboratory

Purple Mountain Laboratory

The Purple Mountain Laboratory, formally the Purple Mountain Network Communications and Security Laboratory and also known in Chinese as the Zijinshan Laboratory, is a major science and technology innovation platform in Nanjing, Jiangsu Province, working on future networks, beyond-5G and 6G communications and endogenous cybersecurity. It was jointly built by Jiangsu Province and the city of Nanjing and officially unveiled on 28 August 2018. Its name refers to Zijinshan, Purple Mountain, the landmark east of central Nanjing. The laboratory gathers more than 1,000 researchers, is directed by academicians including Liu Yunjie of the Chinese Academy of Engineering, with Wu Jiangxing as a chief scientist and You Xiaohu, an academician of the Chinese Academy of Sciences, leading its 6G programme, and it has reported a series of world-first results in deterministic networking and 6G field testing. In July 2023 President Xi Jinping inspected the laboratory, an event that confirmed its standing in China's strategic research system.

Founding and builders

The laboratory was officially unveiled on 28 August 2018 as a joint construction of Jiangsu Province and Nanjing Municipality. Its initial construction drew on three established research forces: Southeast University in Nanjing, a leading centre for mobile communications research; the Jiangsu Future Network Innovation Research Institute, which had been building experimental future network infrastructure in Nanjing; and the PLA Information Engineering University, home of the endogenous security theory associated with academician Wu Jiangxing. This combination explains the laboratory's three-part mission from birth: the future network, next-generation mobile communications, and a distinctive Chinese school of cybersecurity built into systems by design rather than added afterwards.

Leadership

The laboratory is directed by Liu Yunjie, an academician of the Chinese Academy of Engineering described in Chinese reporting as its director and chief scientist, who built his career in data communications and led the future network work in Jiangsu. Wu Jiangxing, the academician who originated endogenous security theory, serves as a chief scientist. You Xiaohu, an academician of the Chinese Academy of Sciences from Southeast University whose career spans China's mobile communications generations, directs the laboratory's 6G research; Chinese reporting in 2025 described him as the laboratory's current director in the context of its 6G programme, reflecting the laboratory's practice of foregrounding the academician leading each major direction. By the laboratory's own reporting in 2023, its research team exceeded 1,000 people, more than 40 per cent of them holding doctorates, with more than 20 postdoctoral researchers, four academicians of the two national academies and more than 70 high-level talents at national and provincial levels.

Future networks and the CENI facility

The laboratory's first pillar is the future network. Nanjing hosts the CENI future network experimental facility, China's national major scientific infrastructure for testing new network architectures, and the laboratory is closely associated with its construction and use. On this foundation the laboratory reported a wide-area deterministic network system, technology that guarantees bounded delay and jitter for traffic crossing long distances, a requirement for industrial control, remote operation and other applications that ordinary best-effort internet service cannot support. Nanjing's position is distinctive in China: reporting describes it as the only city in the Yangtze River Delta simultaneously undertaking the national future network test facility and overall 6G technology research, a dual role that makes the laboratory a national testbed as well as a research institute.

The 6G programme: terahertz records

The laboratory made 6G a core research direction in 2019, the year China officially launched its 6G special project, and built an early lead in terahertz communications, the high-frequency band expected to carry 6G's fastest links. At the beginning of 2022 it completed what it reported as the world's first 6G photonic terahertz real-time wireless transmission experiment, achieving a single-wavelength net rate of 103.125 gigabits per second and a dual-wavelength net rate of 206.25 gigabits per second, then the highest publicly reported record for terahertz real-time wireless communication. The work was carried out with Southeast University, Peng Cheng Laboratory, Fudan University and China Mobile under a government 6G research programme. By the end of 2023 the laboratory reported a real-time transmission rate of 1 terabit per second, again described as a world record in terahertz wireless communication and a hundredfold increase over 5G capacity.

The 6G programme: cell-free networks and field trials

A second 6G line, led by You Xiaohu's team from the laboratory's founding in 2018, is cell-free radio access network technology, which dismantles traditional cell boundaries by synchronising and centrally processing signals, reporting coverage and signal improvements of more than ten times compared with conventional cellular networks, according to the laboratory's researchers. The technology has been trialled in real environments, including an ultra-long-range cell-free communication trial over Taihu Lake with China Unicom and the local fishery management authorities, in which a single station was reported to provide ten times the coverage of 5G, and drone and street-sweeper applications in Nanjing guided through the network within milliseconds. In 2024, at the Global 6G Technology Conference in Nanjing organised by the Future Mobile Communications Forum and the laboratory, it unveiled the world's first 6G field test network integrating communication, intelligence and perception, demonstrating that semantic communication techniques could reach 6G-level transmission capability on existing 4G and 5G infrastructure. Reporting in the following period described further systematic verification of pre-6G technology in low-altitude inspection, industrial manufacturing and physical AI scenarios, alongside the launch of a Nanjing 6G future industry fund cluster.

Endogenous cybersecurity

The laboratory's third pillar is endogenous security, the theory associated with Wu Jiangxing under which network systems are designed with built-in, immune-system-like defence rather than protected only by external, reactive measures. The laboratory conducts basic and frontier research in this field and applies it to network equipment and systems. Endogenous security distinguishes the laboratory from other Chinese network laboratories: its full formal name, the Network Communications and Security Laboratory, records that communications and security were joined in its mandate from the start, and its deterministic network and future network work is designed to carry the security architecture with it.

The presidential inspection of July 2023

On 6 July 2023 President Xi Jinping visited the laboratory during an inspection tour of Nanjing, walking through its exhibition hall and its 6G comprehensive laboratory and learning in detail about its major scientific and technological tasks. Liu Yunjie later recalled an exchange with Xi in December 2014, when Xi had asked whether the future network team had come through, and reported in 2023 that the laboratory had brought together a research team of more than 1,000 people. A presidential inspection of this kind is a formal marker of national significance in China's research system, and it placed the laboratory's network and 6G work publicly among the country's strategic priorities.

Research community and talent

Beyond its headline results, the laboratory functions as a gathering point for China's network research community. Its pervasive communication research centre, whose researchers explain its cell-free and 6G work in public reporting, is one of its constituent research units, and its teams include engineers who joined as the national 6G programme began and have since led field projects of their own. The laboratory co-organises the Global 6G Conference in Nanjing, which has become a regular international meeting point for the field, and its results are presented there as integrated platforms, including a 6G end-to-end integrated test platform, the cell-free radio access network system and integrated sensing and communication systems.

Applications and the low-altitude economy

The laboratory's public demonstrations emphasise application as well as records. Its 6G technology has been shown guiding a medicine-delivery drone over eight kilometres across Nanjing from a pharmacy to the laboratory's own east gate, supporting aerial inspection of fishery resources over 33 kilometres of Taihu Lake, and coordinating autonomous street sweepers through cell-free networks. These trials connect the laboratory to China's developing low-altitude economy and to smart city programmes, and they serve as the verification environments in which its pre-6G systems are being tested during the period before formal 6G standards, not expected to be finalised until around 2028, are set.

Standing and outlook

In less than a decade the Purple Mountain Laboratory has moved from its 2018 unveiling to a documented sequence of firsts: a wide-area deterministic network, the CENI experimental facility role, terahertz transmission records rising from 206 gigabits to 1 terabit per second, the first 6G communication-intelligence-perception field test network, and a presidential inspection. Its structure, a provincially and municipally built platform drawing on a university, a research institute and a military university, is the model of the new Chinese innovation platform: large, mission-directed and built around named academicians. As international 6G standardisation advances towards the end of the decade, the laboratory's field networks and test platforms position it as one of the institutions whose experimental results will feed directly into the standards contest.