Terahertz communication

Q: What is the terahertz frequency region?

While terahertz technologies can be rather complex, terahertz itself is simply a unit of frequency equal to 1 trillion hertz . When it comes to 6G terahertz, the terahertz band in the 6G network ranges from 0.1 to 10 THz . This THz range is a research area for future 6G communication. There are different specifications for the THz range. IEEE ITU defines this range from 0.3 up to 3 THz.

Q: What are terahertz waves?

Terahertz (THz) waves are electromagnetic waves located between microwaves and infrared light, which are used in different areas such as terahertz wireless communication . Wavelengths are in the r ange of 0.03 mm to 3 mm . The THz region is a key research area for 6G because it offers broad contiguous frequency bands to meet the demand for high data transfer rates .

Q: Does 5G use terahertz?

The terahertz band involves frequencies above 100 GHz . 5G only uses frequencies up to 71 GHz however, which can impact the performance of terahertz communication applications .

Q: Will 6G use terahertz frequencies?

The initial 3GPP 6G specification (Release 20) does not focus on the THz frequency range. The first 6G networks based on 3GPP Release 20 are expected around 2030, and they will operate in the established 5G frequency bands and the new FR3 mid-band spectrum (7 Ghz to 24 GHz). THz communication remains an important area of research for later 6G releases as well as applications such as wireless backhaul , sensing and short-range ultra-high data rate links .

THz frequencies for the 6G spectrum

While 5G already uses very high millimeter wave frequencies, 6G research explores even higher frequencies beyond 100 GHz to meet the long-term demand for higher data transmission rates and lower latency. Academic research is currently investigating the use of frequencies of up to 330 GHz. On the path to higher frequency usage, the wireless industry is focusing the first 6G release (3GPP Release 20) on the FR3 and mid-band spectrum (7 GHz to 24 GHz), while the D band (110 GHz to 170 GHz) is being studied as a candidate for later 6G releases.

6G communication will also operate at all frequencies already supported by current 5G networks such as the millimeter wave and traditional sub-8 GHz frequency bands. There are many other applications possible within these frequencies, such as non-destructive imaging (security scanners) and spectroscopy (material analysis).

Overview of 5G and 6G frequency bands.

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THz communication is just one 6G technology component alongside integrated sensing and communication (ISAC) , AI/ML and reconfigurable intelligent surfaces (RIS) . While sub-THz frequencies are not part of the initial 6G specification, they are widely seen as a candidate for later 6G releases and for specialized use cases, such as ultra-high-capacity point-to-point links, where they can deliver maximum throughput and extremely low latencies. THz communication also has potential for exciting new applications such as holographic communication.

Research in THz communication

Rohde & Schwarz is supporting research activities at 6G organizations, universities and research institutes in Europe, Asia and the US. As an active partner in the 6G-TERAKOM project, we are researching the development of a wireless system with integrated antennas that functions in the THz range.

We were also involved in the 6G-ADLANTIK project, which developed technologies and components for THz frequencies based on photonic-electronic integration. Such components can be used for fast data transfers as well as innovative measurement techniques.

RF photonic integration is emerging as a key enabler far beyond 6G research: compact photonic-electronic components can cover microwave, millimeter wave and THz frequencies on a single platform. It can also generate and analyze signals with extremely wide bandwidths.

Components and interfaces are continuing to increase in bandwidth, not only in wireless communication but also in the ultra-broadband interconnects of scaled-up AI data centers . Measurement technologies must scale accordingly. The photonic approaches developed in the 6G-ADLANTIK project, such as photonic THz signal generation with very low phase noise, lay the groundwork for characterizing such ultra-wideband components and links. In parallel, standardization groundwork for THz communication is already underway. For example, the ETSI Industry Specification Group THz (ISG THz) and ITU-R study groups are preparing the basis for THz communication in future 6G releases.

White paper: Fundamentals of THz technology for 6G

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White paper

Fundamentals of THz technology for 6G

This white paper offers an overview of THz fundamentals and relevant properties, with a focus on 6G-based communications.

Download now

Your challenges with testing 6G THz technologies

The THz range presents new challenges for semiconductor components and requires additional channel sounding campaigns to develop new channel models for even higher frequencies.

New semiconductor components are required for the THz range. These components must deliver high output power at extremely high frequencies. This demand for higher bandwidth presents a major challenge for the semiconductor industry because components such as power amplifiers (e.g., monolithic microwave integrated circuits) significantly influence how well the entire system works in terms of output power, efficiency, bandwidth and more.

The development of sub-THz communication (as envisaged for 6G) is only possible with a solid understanding of electromagnetic wave propagation properties. Further study on channel propagation measurements above 100 GHz is therefore essential, as this frequency range is as of yet insufficiently researched. The propagation of sub-THz signals is strongly influenced by human bodies, vehicles and environmental conditions such as rain. Existing 5G channel models must be verified and fine-tuned to correctly reflect the impact of the environment. As such, the development of innovative and accurate THz measurement instruments is crucial to 6G research.

Test solutions for THz communication

Rohde & Schwarz is already actively addressing the requirements for 6G THz communication with innovative test and measurement solutions for signal generation and analysis. Currently, most research activities are focused on the D band, which is one of the most extensively studied candidate bands for longer-term 6G evolution.

Our simple, high-performance setup for the D band consists of:

Benefits of our solutions for 6G THz research

Off-the-shelf instruments that are easy to mount and configure
Fully integrated and calibrated solution with defined frequency and output power
Frontends take up little space as an internal synthesizer provides a local oscillator (LO), meaning no additional analog signal source is needed for excellent phase noise performance
Possibility to further enhance testing solution performance with smart accessories (e.g., bandpass filters and TX power amplifiers)

Want to discuss your specific THz communication test cases with our experts?

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6G test solutions for THz communication applications

R&S®SFI100A wideband IF vector signal generator

Satisfies bandwidth needs for applications such as 6G research, mmW WLAN and automotive radar

R&S®SMW200A vector signal generator

Generates complex, high-quality digitally modulated signals for the most demanding applications

R&S®FSW signal and spectrum analyzer

Supports cross-correlation with multiple input ports and internal multi-path architecture

R&S®FE170ST frontend

Offers exceptional performance in the 110-175 GHz sub-THz frequency range for D-band measurements

R&S®FE170SR frontend

Offers exceptional performance in the 110-175 GHz sub-THz frequency range for D-band measurements

R&S®FE110ST frontend

Offers exceptional performance in the 70-110 GHz range for sub-THz 6G research and automotive radar

R&S®FE110SR frontend

Offers exceptional performance in the 70-110 GHz range for sub-THz 6G research and automotive radar

R&S®FC330ST Frequency converter

Ensures precision across a broad frequency spectrum covering 220-330 GHz for H-band measurements

R&S®FC330SR Frequency converter

Ensures precision across a broad frequency spectrum covering 220-330 GHz for H-band measurements

6G THz communications in the press

Press Releases Aug 14, 2025

The next wave of test and measurement: Rohde & Schwarz to highlight its solutions at the EuMW 2025 in Utrecht

Rohde & Schwarz invites attendees to EuMW 2025 in Utrecht to “Discover the next wave of test and measurement” at booth A026 in the Jaarbeurs Utrecht. A key highlight of the exhibition will be the game-changing FSWX signal and spectrum analyzer.