Developments in mobile technology are moving constantly towards increasing bandwidths, 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 TC RSE converter box. The leading analog signal generator, the SMA100B, provides 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 FSW featuring the new, unique 8.3 GHz bandwidth option 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 NGP800 from Rohde & Schwarz plays a vital role powering various parts and components in this setup.
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.