Active THz Transceiver Components

与工作在纯光波长或RF/微波频率下的无线电相比，太赫兹频率下极高的绝对带宽和高相对带宽的组合，再加上在所谓的“THz-GAP”下操作的技术的严重性能限制，给依赖于高信号完整性的现代数字传输方案带来了独特的挑战。由于在太赫兹频率下还不能直接使用数字信号处理器，因此信号需要在太赫兹频率范围内进行频移。这种频移是由收发信机执行的，收发信机可以基于全电子、全光子或混合电子-光子技术来实现。后一种方法是当今最有前途的发展方向，因为它允许结合这两个领域的独特优势，即基于电子的THz收发机的低接收噪声、高发射功率和高功能集成密度，以及基于光子学的THz信号产生的高频谱纯度和高质量的相位和频率控制。Meteracom的项目B2旨在发展对基于电子和光子技术的THz收发机设计的理论和实验理解，以及优化其特定应用特性的电路设计和仿真方法，以期提高其数据速率能力、调制格式的通用性和系统增益。该项目还将提供一个技术平台，用于对其他项目框架中调查的太赫兹计量概念进行实验验证。将研究工作在220 GHz至325 GHz的WR3频率范围内的电子太赫兹收发电路，重点是超宽带(&GT；60 GHz)通道带宽，如在太赫兹通信、雷达和计量应用中遇到的。在一种基于理论分析和系统级CAD模拟的面向应用的自上而下的设计方法中，将研究和实验评估通信信号的矢量信号退化对外差、正交电子太赫兹发射接收前端损伤的敏感性，并最终在专用收发电路设计中将其最小化。利用锁模激光器来实现有源太赫兹收发信机，利用锁模激光器产生高稳定和光谱纯的基于光子学的信号，既可以作为可调谐的太赫兹信号源，也可以作为稳定的本地振荡器用于电子收发信机。本项目的实验验证将包括单个电子和光子收发信机组件的时域和频域特性以及使用背靠背配置中的组合光电子收发机以及现有技术中具有空中接口的现有THz收发机的完整数据传输实验。

Compared to radios operating at purely optical wavelengths or RF/microwave frequencies, the combination of extremely high absolute bandwidths and high relative bandwidths in the THz frequency regime, paired with the severe performance limitations of technologies operating in the so-called "THz-gap", imposes unique challenges on modern digital transmission schemes relying on high signal integrity. Since no direct DSP is yet possible at THz frequencies, signals need to be frequency-shifted into and from the THz range. This frequency-shifting is performed by the transceiver, which can be implemented based either on fully electronic, fully photonic or mixed electronic-photonic technologies. The latter approach is today the most promising way forward since it allows to combine the unique advantages of both domains, namely the low receiver noise, high transmit power and high functional integration density of electronics-based THz transceivers, with the high spectral purity and high quality phase and frequency control of photonics-based THz signal generation.Project B2 of Meteracom aims at developing a theoretical and experimental understanding of the design of THz transceivers based on electronic and photonic technologies, as well as circuit design and simulation methods of optimizing their application-specific characteristics, in view of pushing their data rate capability, modulation format versatility and system gain. The project will also provide a technology platform for the experimental validation of the Terahertz metrology concepts investigated in the frame of the other projects.Electronic THz transceiver circuits operating within the WR3 frequency range from 220 to 325 GHz will be investigated, with a particular focus on ultra-wideband (> 60 GHz) channel bandwidths, as encountered in THz communication, radar and metrology applications. In an application-oriented top-down design approach based on theoretical analysis and system-level CAD simulations, the sensitivity of the vectorial signal degradation of communication signals on the impairments of heterodyne, quadrature electronic THz transmit receive frontends will be studied, experimentally evaluated, and finally minimized in dedicated transceiver circuit design.Complementing the active THz transceivers, highly stable and spectrally pure photonics-based signal generation with the help of mode-locked lasers will be investigated, serving, both, as a tunable THz signal source and as a stable local oscillator to the electronic transceivers.Experimental validation in this project will comprise the time and frequency domain characterisation of the individual electronic and photonic transceiver components, as well as complete data transmission experiments using combined photonic-electronic transceivers in a back-to-back configuration, as well as existing THz transceivers with air interface from prior art.