Toward the first D-band Point to multipoint wireless system field test Claudio Paoloni 1 , Rupa Basu 1 , Marcel Burhenn 2 , Maruf Hossain 9 , Daniel Huebsch 2 , Viktor Krozer 3 , Trung Le 2 , Rosa Letizia 1 , Ernesto Limiti 5 , François Magne 4 , Marc Marilier 6 , Antonio Ramirez 7 , Jeevan M Rao 1 , Giacomo Ulisse 3 , Borja Vidal 8 , Hadi Yacob 9 , 1 Engineering Department, Lancaster University, Lancaster, United Kingdom, LA1 4YW email: c.paoloni@lancaster.ac.uk 2 Hübner GmbH & Co. KG, Kassel 34123, Germany 3 Goethe University Frankfurt/M, Frankfurt 60323, Germany 4 When Ab, Paris, France 5 University of Rome, Tor Vergata, Rome, Italy 6 OMMIC S.A.S., Limeil Brevannes, 94453, France 7 Fibernova Systems, Valencia 46022, Spain 8 Universitat Politècnica de València, Valencia 46022, Spain 9 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Berlin, Germany Abstract— The European Commission Horizon 2020 ULTRAWAVE “Ultra capacity wireless layer beyond 100 GHz based on millimeter waves” is in the final stage of development. The first ever field test of a D-band point to multipoint wireless system will be performed in a real environment. The ULTRAWAVE wireless system comprises a D-band Transmission Hub to produce a 30 degree sector with 600 m radius with multi gigabit per second data rate and a number of compact D-band terminals. The terminals will be distributed at different distances from the transmission hub to recreate real deployment condition. The paper describes the latest update on the development of the ULTRAWAVE systems and the field test set up. Keywords— D-band; point to multipoint, wireless, terminals, TWT, transmissio hub, 6G, 5G, backhaul I. INTRODUCTION Point to multipoint distribution (PmP) with high capacity at D-band (141 - 148.5 GHz) is the ambitious aim of the European Commission Horizon 2020 ULTRAWAVE “Ultra capacity wireless layer beyond 100 GHz based on millimeter waves” [1]- [4]. The advantages of point to multipoint distribution in comparison to other modalities, such as point to point (PtP), beam steering or multiple beam are the flexibility of frequency allocation, easy alignment of terminals, low Total Cost of Operation (TCO), small footprint of front ends, easy reconfiguration of the network to adapt to new traffic needs, low latency, low complexity of the radio and the antenna system ( [5] – [7]). Differently, from the other distribution modalities that use high gain high directivity antennas, PmP distributes the signal over a wide area by a wide beam, generated by a low gain antenna. The reduction in gain with respect to typical PtP antennas (>40 dBi) is in the order of 20 dBi, that have to be compensated, for achieving a same range as an equivalent PtP link, by higher transmission power. Above 100 GHz, solid state power amplifiers have limited output power. Specifically, at D-band, state of the art power amplifiers can provide about 20 dBm output power [8] - [10]. This power does not satisfy the link budget for wide beam hundreds of meters long, providing sufficient signal to noise ratio (SNR) for operation in real environment. This is the main reason why it is so challenging to enable PmP wireless distribution above 100 GHz. The development and introduction of Traveling Wave Tubes (TWTs) as power amplifier has opened new opportunities to enable sub-THz PmP wireless system [11]. TWTs can provide output power in the range of 40 dBm at D-band, over more than 10 GHz bandwidth [12], [13]. That performance permits to enable wide beam to transport tens of Gb/s data rate, with more than 100 Gb/s/km 2 area capacity, with high SNR supporting up to 64QAM over radial sector with 600 m or more radius. The ULTRAWAVE wireless concept is to distribute internet at high capacity by sectors in PmP deployed where needed. Each sector is generated by a transmission hub. Terminals are distributed over the sector to serve base stations at ground level, with a flexible allocation of channels. The transmission hub and the terminals at D-band use a simple Radio topology. This is an important design aspects, since the electronics at D-band is very challenging, not only in terms of mmMICs (millimeter wave Monolithic Integrated Circuits) but also interconnections, transitions, assembly. The ULTRAWAVE project has developed the full D-band PmP wireless system, including the mmMIC chipset, antennas, filters, The work has received funding from the European Union’s Horizon 2020 research and innovation programs under grant agreement no 762119. This work reflects only the author view’s and the Commission is not responsible of any use that may be made of the information it contains.