This work describes the diffuse scattering response of a terahertz data stream on metallic rough surfaces to investigate its influence on wireless channels. The measurements are performed using a wireless link with carrier frequencies operating from 100-400 GHz with transmitter and receiver modules mounted on separate rotatable rails. The acquired data are analyzed to determine the dependence of scattering pattern on surface roughness parameters, including rms height and correlation length. Fundamentals of scattering and reflections are explained and integral equation method (IEM) with an exponential correlation function is verified for theoretical predictions. The implications of surface roughness for non-line-of-sight (NLOS) paths in non-specular directions are discussed for the first time.
With increasing interest in wireless communications at terahertz (THz) frequencies, investigations on the link performance in indoor and outdoor environments are required. In order to analyze the signal impairments caused by outdoor weathers and indoor surface reflections, wireless channels are employed using a continuous wave (CW) signal at five discrete frequencies (100, 200, 300, 400 and 625 GHz) with a data rate of several Gb/sec. The link performance in rainy, snowy, and atmospheric turbulence weathers is analyzed by measuring the power and bit-errorratios (BERs). Scattering effects due to reflection by indoor rough surfaces are investigated. Predictions for power attenuation and link performance in these scenarios are conducted and compared with experimental results.
Based on parallel-plate waveguides (PWWGs), we have developed both passive and active terahertz (THz) sensors, filters, splitters, and switches. We utilize the PPWG since it has excellent waveguiding properties with a simple geometry that allows for incorporation of unique electromagnetic functionalities. A few passive devices are discussed while the focus remains on active devices. The active control is enabled by our innovation to incorporate liquid metals, which can be relocated by application of a small electrical voltage (< 4V), as part of the waveguide geometry itself. The device geometry directly affects the device performance (e.g., frequency band of operation, channel output power). Therefore, by moving the liquid metal, the geometry is reconfigured which results in altering the device function. To show the practicality of these devices to be used for THz wireless communications, we demonstrate the ability of these devices to support a 1 Gb/s data stream on a THz carrier wave and show that this signal can be successfully switched with high modulation depths of ±40 dB. These results show the strong promise of these components to form important signal processing building blocks in the future infrastructure of THz wireless communications.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.