基于光混频的太赫兹双频通信天线的设计和仿真

Design and simulation of dual-frequency terahertz antenna for wireless communication by photomixing

比较了宽带天线和窄带天线的优缺点,设计了一种用于太赫兹无线通信的双频天线.其是由两个分层且垂直分布的偶极天线组成,两天线处于高度不同的介质层上以避免互相干扰和短路,并具有各自的THz扼流圈以提高性能.上层天线通过介质层开孔处的金属探针连接到低温砷化镓衬底,实现了和下层天线共用一个光照区.上层和下层天线尺寸不同,具有不同的工作频率,在各自的偏置电压回路控制下,不需要调整泵浦光就能实现垂直偏振的双频工作.通过调整尺寸,还可使工作频率落在不同的大气窗口内.在0.21 THz、0.35 THz、0.41 THz、0.68 THz、0.85 THz和0.93 THz等大气窗口内,其保持了偶极天线在单频点具有较高性能的优点:最佳总效率分别为14.9%、28.4%、33.9%、28.4%、21.6%和19.8%,最大实际增益分别为2.99 dB、10.6 dB、11.8 dB、18.4 dB、18.2 dB和18.3 dB.

After comparing wide-band antenna and narrow-band antenna, a dual-frequency Terahertz antenna for wireless communication was designed. It consists of two dipole antennas which are located on two different layers and arranged vertically to avoid connection and interaction. The two dipoles both have THz chokes to improve performance, and different sizes to operate in two different frequencies. The upper dipole uses metal probe to connect the LT-GaAs substrate through the hole of substrate and shares the same photomixer with the lower dipole. The photomixer can be lighted by the same light for pumping, while the two dipoles can be controlled by different circuit for bias. So they can work at different frequencies and in vertical direction of polarizations. They can be adjused for the air’s low-loss frequencies by changing the size. The dual-frequency antenna has higher performance because of the two dipole antennas. At the air’s low-loss frequencies of 0.21 THz, 0.35 THz, 0.41 THz, 0.68 THz, 0.85 THz and 0.93 THz, it has total efficiencies of 14.9%, 28.4%, 33.9%, 28.4% and 21.6% respectively, and max realized gains of 2.99 dB, 10.6 dB, 11.8 dB, 18.4dB, 18.2 dB and 18.3 dB respectively.