High-definition video transmitted over 1.2 kilometres using superconducting receiver

• New terahertz wireless transmission tech has broken a world record

• Researchers streamed high-definition video over 1.2 kilometers

• The record breaking test shows promise for the future of wireless comms

A research team led by the Purple Mountain Observatory of the Chinese Academy of Sciences (CAS) has successfully conducted the first-ever kilometer-level terahertz wireless communication transmission.

Carried out at the submillimeter wave astronomical observation base of Xueshan Pasture in Haixi Prefecture, Qinghai Province, the test used superconducting receiving technology to transmit high-definition video signals over a distance of 1.2 kilometres.

This marks a significant breakthrough in the field of future communications technology, setting a world record for the longest-distance terahertz transmission above the 0.5THz frequency band.

Terahertz technology is the future of communications 

Terahertz communication, positioned between microwaves and light waves, is widely regarded as the "new frontier" in future communication systems. It offers strong penetration, an extremely wide bandwidth, and the potential for higher data transmission rates than current technologies.

Given its exceptional capabilities, terahertz technology is seen as crucial to the development of next-generation communication systems, including applications in space communications, medical imaging, and astronomical observations.

One of the key challenges in terahertz communication is the significant signal attenuation that occurs during transmission, making long-distance communication particularly difficult. To address this issue, the research team utilized superconducting receiver technology, which provides high sensitivity and minimal signal loss.

The experiment took place at an altitude of over 4,000 meters on the Qinghai-Tibet Plateau. Despite the transmitting end having a signal power of just 10 microwatts — equivalent to one-millionth of the transmission intensity of a mobile phone base station — the superconducting receiver successfully captured the signals.

This achievement is the result of more than 30 years of research by Chinese scientists. Since the 1990s, China has been studying terahertz astronomical detection technology, with a focus on superconducting detector technology. Li Jing, a researcher from the Purple Mountain Observatory, likened the shift from microwave to terahertz communication to upgrading from a two-lane road to a six- or eight-lane highway.

The successful demonstration of terahertz communication technology opens new possibilities for its application in various fields, from high-speed data transmission to telemedicine and security monitoring.

9月27日至10月1日，中国科学院紫金山天文台牵头的联合实验团队，在青海省海西州雪山牧场成功实现基于超导接收的高清视频信号公里级太赫兹/亚毫米波无线通信传输。这是国际首次将高灵敏度超导接收机技术成功应用于远距离太赫兹无线通信系统，也是0.5THz频段以上迄今最远距离的太赫兹无线通信传输实验。中国工程物理研究院电子工程研究所和上海师范大学参与组织联合实验，中国电科54所、中国科学院理化技术研究所和长春光学精密机械与物理研究所参与部分研制。

太赫兹通信是解决未来空间海量数据实时传输与落地难题的重要技术手段，但面临因信号衰减严重而难以远距离传输等瓶颈，发射机功率、接收系统灵敏度以及传输场景等是影响远距离太赫兹通信的重要因素。在适宜太赫兹/亚毫米波天文观测的台址环境，将超高灵敏度和高增益的太赫兹天文望远镜系统与太赫兹通信系统相结合，可显著提升太赫兹通信传输距离。

联合实验团队完成了适应极端环境的太赫兹高灵敏度超导接收机、太赫兹高效倍频链、中频带宽扩展和超宽带调制发射等多项关键技术攻关，全自主研制了一套0.5THz频段基于超导隧道结外差混频接收的全电子学太赫兹通信系统。在青海省海西州雪山牧场亚毫米波天文观测基地（海拔约4300米处）实现了高清视频信号的太赫兹无线通信传输，传输频率为0.5THz，传输距离为1.2公里，信号发射功率仅10微瓦。本次实验充分验证了利用太赫兹/亚毫米波超导接收系统开展太赫兹通信的独特优势，完成了地面外场高速数据太赫兹通信传输实验验证及系统性能评估，为未来空间/空地大容量太赫兹通信、以及雪山牧场亚毫米波多学科平台建设奠定关键技术基础。

相关工作得到国家自然科学基金委员会、科技部、中国科学院、青海省科技厅、青海省海西州人民政府等的支持。