A Terahertz Wireless Communication Link Using a Superheterodyne Approach

This article presents a wireless communication point-to-point link operated in the low terahertz (THz) range, at a center frequency of 300GHz. The link is composed of all-electronic components based on monolithic millimeter wave integrated circuits fabricated in an InGaAs metamorphic high electron mobility transistor technology. Different configurations and architectures are compared and analyzed. The superheterodyne approach proves to be the most promising of all, being compliant with the new IEEE standard for 100Gb/s wireless transmissions and showing compatibility to accessible, already available modems. The first option of realizing the superheterodyne configuration is by combining the 300-GHz transmitter and receiver with of-the-shelf up and down converters operating at a center frequency of 10GHz. In this case, data rates of up to 24Gb/s are achieved. The second option employs a fast arbitrary waveform generator that uses a carrier frequency to up-convert the baseband data. In this case, data rates of up to 60Gb/s and transmission distances of up to 10m are achieved with complex modulated signals like 16-QAM and 32-QAM. The baseband signal is composed of pseudo-random binary sequences and is analyzed offline using fast analog to digital converters. In superheterodyne configuration, multichannel transmission is demonstrated. Channel data rates of 10.2Gb/s using 64-QAM are achieved. The successful transmission of aggregated channels in this configuration shows the potential of THz communication for future high data rate applications.