Page 10 - ITU Journal Future and evolving technologies Volume 2 (2021), Issue 7 – Terahertz communications

ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 7

Terahertz wireless communications in space

Pages 31–38
Meltem Civas, Ozgur B. Akan

The New Space Era has increased communication traffic in space by new space missions led by public
space agencies and private companies. Mars colonization is also targeted by crewed missions in the
near future. Due to increasing space traffic near Earth and Mars, the bandwidth is getting congested.
Moreover, the downlink performance of the current missions is not satisfactory in terms of delay and
data rate. Therefore, to meet the increasing demand in space links, Terahertz band (0.1–10 THz)
wireless communications are proposed in this study. In line with this, we discuss the major challenges
that the realization of THz band space links pose and possible solutions. Moreover, we simulate Mars-
space THz links for the case of a clear Mars atmosphere, and a heavy dust storm to show that even in
the worst conditions, a large bandwidth is available for Mars communication traffic.
View Article

Fundamental limits of high-efficiency silicon and compound

semiconductor power amplifiers in 100–300 GHz bands

Pages 39–50
James F. Buckwalter, Mark J. W. Rodwell, Kang Ning, Ahmed Ahmed, Andrea Arias-Purdue, Jeff
Chien, Everett O'Malley, Eythan Lam

This paper reviews the requirements for future digital arrays in terms of power amplifier requirements
for output power and efficiency and the device technologies that will realize future energy-efficient
communication and sensing electronics for the upper millimeter-wave bands (100–300 GHz).
Fundamental device technologies are reviewed to compare the needs for compound semiconductors and
silicon processes. Power amplifier circuit design above 100 GHz is reviewed based on load line and
matching element losses. We present recently presented class-A and class-B PAs based on a InP HBT
process that have demonstrated record efficiency and power around 140 GHz while discussing circuit
techniques that can be applied in a variety of integrated circuits.
View Article

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