Rohde & Schwarz Demonstrates Sub-THz Wideband Signal Analysis

Paving the way to research in the terahertz frequency range, RF Test & Measurement experts, Rohde & Schwarz, has demonstrated a new setup that enables multi gigabit data transmission in the D-Band at 140 GHz. The new setup uses the R&S FSW high-end signal and spectrum analyzer equipped with an R&S FSW-B8001 option, supporting an unparalleled 8.3 GHz internal analysis bandwidth.

Developments in mobile technology are moving constantly towards increasing bandwidths and enabling increasingly high data throughput. The Rohde & Schwarz setup represents some of the first research exploring data transmission at sub-THz frequencies featuring ultra-wide bandwidths. In the setup, a wideband-baseband signal is upconverted to the selected 140 GHz frequency via a R&S TC RSE converter box. The R&S SMA100B Analog Signal Generator is used to provide the local oscillator frequency to the upconverter.

The transmission is carried out over-the-air, with the converter connected to a horn antenna. The transmitted signal is received via another horn antenna and downconverted. The R&S FSW featuring the new, unique 8.3 GHz bandwidth option R&S FSW-B8001 analyzes the signal, carrying out signal quality measurements such as error vector magnitude (EVM) to assess the performance of the transmission. Various common modulation formats are demonstrated. The new four-channel power supply R&S NGP800 plays a vital role powering various parts and components in this setup.

Rohde & Schwarz Supports Starting Research at THz Frequencies

As wireless communications and sensing technologies are advancing, the need for higher bandwidths is becoming apparent. These developments push the frequency boundaries into the sub-THz and THz frequency range and, continuing the process started with 5G, make testing over-the-air (OTA) mandatory. At these frequencies, RF frontends become even more integrated, and their characterization in terms of signal quality (EVM) and out-of-band emission (ACLR, SEM, spurious) requires a flexible OTA test setup, covering a wide frequency range, from microwave and mmWave to sub-THz.

The proposed setup can easily be installed into the R&S ATS1000 antenna test system. This enables design engineers to characterize RF frontend prototypes and reference designs intended to be used in future devices that support cellular and non-cellular technologies and are using much wider bandwidths. For example, IEEE’s 802.11ay standard allows channel bonding that creates a signal with more than 8 GHz of bandwidth already today. The R&S FSW is currently the only signal and spectrum analyzer in the world supporting the needed bandwidth internally for such applications, significantly facilitating complex setups in R&D.

A demonstration in the chosen frequency range was supposed to be carried out at 6G Wireless Summit, hosted by the University of Oulu and held at Levi, Finland . Since the summit will be held virtually, the setup will be shown in an upcoming video, available soon on Rohde & Schwarz social media channels.