To support 6G research, NI has developed a real-time sub THz software-defined radio (SDR) built on NI’s mmWave transceiver system (MTS) and Virginia Diodes’ (VDI) radio heads. Using the VDI radio heads, the frequency range of the MTS extends into the sub THz range.
NI’s MTS offers modular baseband and IF components that can be combined with FPGAs to build the most basic over-the-air system and expanded to create complex MIMO systems with extensive digital signal processing. VDIs’ radio heads cover a wide variety of frequency bands in the sub THz range. The two combined create a powerful testbed. The NI and VDI sub THz testbed provides up to 2 GHz instantaneous bandwidth and frequency ranges between 110 to 170 GHz.
NI offers two software reference designs built around the NI MTS, one for channel sounding, the other a single carrier physical layer communications link.
- The channel sounding reference design is intended for a single transmitter, single receiver configuration and enables users to make basic channel sounding measurements, such as channel impulse response, time of arrival and path loss.
- The single carrier physical layer reference design is designed for systems in single input single output (SISO) up to 4 x 4 MIMO configurations, with 2 GHz real-time bandwidth.
For each reference design, the software front panel gives users a real-time visualization of system level performance.
All signal processing, including coding, occurs in real-time on FPGAs added to the base MTS system. The total system throughput is dependent on the frame structure and the number of channels used, equalling 7.2 Gbps per channel using the default frame structure.
Because this testbed is built using SDRs and FPGAs, the software can be upgraded and customized to meet various research needs and applications. Users can leverage existing software reference designs for channel sounding or wireless communications protocols to create a real-time testbed for 6G research.
The development cycle for a typical wireless standard is approximately 10 years, so wireless communications researchers are beginning to investigate the technology and ideas that will serve as the foundation of the next-generation or 6G. The sub THz and THz frequencies will likely host numerous as yet unknown applications for communications, prompting significant research in the foreseeable future.
“Researchers need access to sub THz testbeds to prototype multiple wireless use cases. These testbeds must be highly flexible but also offer cutting edge performance in order to explore the boundaries of wireless performance at these very high frequencies.” — James Kimery, director of wireless research, NI
“It seems D-Band is now the new E-Band.” — Gerhard Schoenthal, COO of VDI