GRENOBLE, France - May 7, 2020 - As countries around the world begin rolling out 5G wireless networks, CEA-Leti is looking ahead to sixth-generation technologies that will surpass the data-transfer capability of 5G.
- Wireless communication in millimeter wave (mmWave) bands, which range from 20 GHz to 300 GHz, is expected to be a key enabling technology for 6G wireless systems, because the huge available bandwidth can accommodate ultra-high data-rate communications. Within that range of mmWave bands CEA-Leti’s research is investigating D-band, a new spectrum at 140 GHz that may play a major role for 6G wireless communication.
- In a paper written for the 6G Wireless Summit, a March event that was cancelled because of the coronavirus pandemic, CEA-Leti and Siradel, a French engineering firm, said researchers are considering several beyond-5G applications for these systems. These include high-capacity backhaul, enhanced hot-spot kiosks and short-range device-to-device communication. These applications’ data-transfer speed requirements, typically greater than 100 Gbps per cell or per link, exceed the capability of 5G, and are not affected by the main constraints imposed by the sub-THz frequencies.
Scenarios envisaged for wireless connectivity in sub-THz bands associated KPIs
- The paper, titled "Technology Roadmap for Beyond 5G Wireless Connectivity in D-band"1, provided an overview of those potential applications and the challenges to realizing them, and presented scenarios for applications in the new spectrum. It also discussed the trade-offs between scenario requirements, and current silicon-technology limits to building a 6G roadmap.
Severe constraints on antenna directivity and alignment
Challenges to using D-band wireless communication include free-space wave-propagation losses that increase with the square of the frequency and have to be compensated for using high-gain antennas. That entails severe constraints on antenna directivity and alignment," said Jean-Baptiste Doré, a CEA-Leti scientist and one of the authors of the paper.
- The constraints include physical barriers to sub-THz wave propagation, which can be blocked or strongly attenuated by walls, trees or even windows. Even in a clear propagation path, high-gain antennas are required. To address this challenge, CEA-Leti is designing technologies that are beyond state of the art with high directivity and an electronically steerable antenna
Ray-tracing tool from SIRADEL predicts the propagation of in-street back-haul for sub-THz wireless performance assesment. The tool benefits from detailed 3D representations to get a realistic prediction of the blockages and losses due to trees and street or indoor furniture.
Subterahertz hardware integrated circuit technologies. ASK: amplitude-shift keying; PSK: phase-shift keying; QAM: quadrature amplitude modulation; QPSK: quadrature phase-shift keying; InP: indium phosphide; mHEMTs: metamorphic high electron mobility transistors; GaAs: gallium arsenide; OOK: on-off keying.
- Because CMOS technologies cannot produce devices that deliver the maximum transistor frequency needed for sub-THz applications, CEA-Leti is investigating optimized RF circuit designs with innovative architectures for these applications, and new materials and devices to address D-band frequencies and beyond.
- Two recent papers were accepted for presentation at IMS2020 and RFIC2020 concerning low-noise amplifiers and programmable high-order frequency multipliers for channel bonding, respectively.
For device-to-device communication, we have demonstrated that is possible to reach multi-Gbps throughput using spatial multiplexing and a simple RF architecture," Doré said. "The main outcome is that with the proposed mixed-signal, analog & digital, the required power delivered by transistors is limited to microwatts (10^-6 Watts) which makes CMOS technologies possible.
- The design of key enabler technologies for 6G has already started. This work includes the investigation of new materials and devices for the sub-THz band, enhanced RF CMOS architectures and antenna systems as well as high-performance digital processing. CEA-Leti teams also are investigating heterogeneous integrations on system-on-chip and/or system-in-package.
1Jean-Baptiste Doré, Didier Belot, Éric Mercier, Simon Bicaïs, Grégory Gougeon, Yoann Corre, Benoît Miscopein, Dimitri Kténas, Emilio Calvanese Strinatti "Technology Roadmap for Beyond 5G Wireless Connectivity in D-band", 2020 2nd 6G Wireless Summit (6GSummit) , March 2020, Levi, Finland.
José Luis González-Jiménez, Cédric Dehos, Nicolas Cassiau, "Channel bonding transceivers for 6G future network", 2020 2nd 6G Wireless Summit (6GSummit) , March 2020, Levi, Finland.
Alexandre Siligaris, José Luis Gonzalez-Jimenez, Benjamin Blampey, Abdelaziz Hamani, Abdesamat Boulmirat, Cedric Dehos, "A Multichannel Programmable High Order Frequency Multiplier for Channel Bonding and Full Duplex Transceivers at 60 GHz Band", accepted at RFIC 2020 .
Abdelaziz Hamani, Alexandre Siligaris, Benjamin Blampey, Cedric Dehos, José Luis Gonzalez Jimenez, "A 125.5-157 GHz 8 dB NF and 16 dB of Gain D-band Low Noise Amplifier in CMOS SOI 45 nm", accepted at IMS 2020 .
« F. F. Manzillo, J. Luis Gonzalez-Jimenez, A. Clemente, A. Siligaris, B. Blampey and C. Dehos, "Low-cost, High-Gain Antenna Module Integrating a CMOS Frequency Multiplier Driver for Communications at D-band," 2019 IEEE Radio Frequency Integrated Circuits Symposium (RFIC), Boston, MA, USA, 2019, pp. 19-22,"