Abstract

Sub-terahertz (sub-THz) imaging is an emerging field of research with promising applications in short-range imaging, including security screening and biomedical diagnostics. Amplifiers are critical components of sub-THz imaging systems because they play key roles in signal amplification and noise reduction. This review paper provides an overview of sub-THz power amplifiers (PAs). The study also examines recent advances in sub-THz PA technology, including distributed amplifiers, broadband amplifiers, and low-noise amplifiers (LNAs). The paper then discusses the current state of sub-THz imaging and sensing techniques for security and biomedical applications, including millimeter-wave body scanners, sub-THz spectroscopy, and sub-THz microscopy. Finally, the paper discusses the challenges and future prospects for sub-THz imaging, including the need for improved amplifier performance and integration with other imaging modalities. Overall, this review provides a comprehensive overview of sub-THz amplifier technology and its applications in short-range imaging, highlighting the potential for sub-THz imaging to transform security and biomedical imaging fields.

Key words: Amplifiers; Sub-terahertz amplifier; Power amplifier.