强激光与粒子束, 2016, 28 (3): 033102, 网络出版: 2016-03-28
THz固定无线链路在大气中的特性
Characteristics of fixed THz wireless links in atmosphere
太赫兹 大气传输 连续体吸收 太赫兹无线通信 通道容量 terahertz atmospheric propagation continuum absorption THz wireless communication channel capacity
摘要
基于宽带太赫兹(THz)波的短距离宽带高数据率无线通讯是可行的。利用THz波大气传输衰减模型和经验的水汽连续体吸收,结合HITRAN数据库,发展了在THz频段电磁通信的一个新的传输模型,形成了对宽频THz波在地表真实大气中水平传输衰减、路径损耗和信道容量的数值模拟能力;提出了100~900 GHz频段的五个可行的通信信道。相比低于100 GHz的无线通信频带,虽然这五个信道具有的更大的自由传输衰减损耗,以及大气分子和水滴吸收衰减降低了通信数据率,但通过增加发射和接收天线增益,仍然可以在短距离实现THz低频带尤其是100~500 GHz的高数据率无线通讯。
Abstract
Broadband wireless access over short distances with fixed THz wireless links is very promising. A new model of atmospheric transmission of terahertz communication is developed based on the radiation transmission theory and the continuum absorption phenomenon using data from the HITRAN database. The attenuation, the path loss and the channel capacity of THz atmospheric propagation are investigated by means of numerical simulation. The THz wave atmospheric attenuation experimental results obtained with the THz-time domain spectroscopy (THz-TDS) technique is analyzed by this new model. The intensity and the location of the observed absorption lines are in good agreement with the spectral databases. Five channels ranging from 100 to 900 GHz are analyzed. Nevertheless, contrary to the wireless links in the lower GHz-bands, the transmittable data rates are reduced in this frequency range because of the high free-space path loss and attenuation due to molecules in air or water droplets. As demonstrated here, high transmission data rates larger than 10 Gbps can be reached via these channels within short distances if antennas with high gains are used.
王玉文, 董志伟, 周逊, 李瀚宇. THz固定无线链路在大气中的特性[J]. 强激光与粒子束, 2016, 28(3): 033102. Wang Yuwen, Dong Zhiwei, Zhou Xun, Li Hanyu. Characteristics of fixed THz wireless links in atmosphere[J]. High Power Laser and Particle Beams, 2016, 28(3): 033102.