Patrick Cabrol

Measurement and Characterization of Various Outdoor 60 GHz Diffracted and Scattered Paths

This paper investigates diffracted and scattered waves in unlicensed millimeter wave mobile-to-mobile, access and backhaul radio links. Narrowband 60 GHz measurements of diffraction at building corners, and scattering by a car, lamppost and building, as well as blocking by humans are presented. Semi-analytical corner diffraction and human blocking models are proposed and verified based on the measurements. Analysis of the diffraction and scattering shows that the contributions from vehicular and lamppost scattered paths can be dominant compared to corner diffracted paths. Measurements also show that the majority of power from building scattering arrives in and near the horizontal plane containing the transmit and receive antennas.

60 GHz patch antenna array on low cost Liquid-Crystal Polymer (LCP) substrate

Millimeter wave communications promises to enable the very high data rates demanded of 5G networks, but there are several hurdles that must be negotiated first. One of these hurdles is the small energy collecting capability of the small aperture antennas at these wavelengths. High gain antennas are required to overcome this limitation. The 60 GHz band is of particular interest due to the large 7-9 GHz of unlicensed spectrum available. The often cited atmospheric absorption in the band (~13dB/km) is easily tolerated in the 100-200m links envisioned for 5G networks. In order to test the feasibility of a 60GHz network, a platform is being constructed and a low cost, high gain antenna is required. For a low cost and small size solution, a low profile microstrip phased array antenna has been designed and fabricated on low-loss, two-layer Liquid Crystal Polymer (LCP) substrate. 4×4, 8×8 antenna array prototypes have been characterized and the results are described.

60 GHz investigation of building scattering at 2 GHz using a scale model

In this work, we investigate building scattering at 2 GHz by performing 60 GHz scattering measurements on a 1/30 scale building model. The materials used to build this model were chosen to have similar reflected and transmitted power characteristics at 60 GHz to common building materials at 2 GHz. Co-polarized and cross-polarized scattering measurements of the model were performed with and without furniture and the front building surface. Near the specular direction, results show that the contribution from waves that enter a building, internally scatter and/or reflect, and then exit the building are not significant compared to those that only interact with the features on the front building surface. However, away from the specular direction, this contribution can be observed.

Exploring the possibility of Full-Duplex operations in mmWave 5G systems

Recent developments in the communications industry to accommodate user demand for ubiquitous, instantaneous over the air access to multimedia rich content has made spectrum utilization efficiency one of the key research topics. Full-Duplex radios have great potential to improve spectrum utilization efficiency and are well-studied for below 6 GHz applications. In this paper, we explore the possibility of mmWave Full-Duplex operation in 5G. We group the Full-Duplex radio system components into four modules: antenna systems, analog frontend and digital baseband self-interference cancellers, and protocol stack enhancements. We create a system model to analyze link-budget and determine the usable range for Full-Duplex operation by focusing on antenna systems, analog RF frontend design assumptions, and the channel models. We also highlight tradeoffs for employing cancellation techniques and criteria for protocol stack enhancements.

EdgeLink™ mmW Mesh Transport experiments in the Berlin 5G-Crosshaul Testbed

This paper presents the performance results for a series of outdoor experiments conducted on a fifth generation (5G) mmW Mesh Transport system to show multiplexing of high throughput fronthaul (FH) and backhaul (BH) traffic over a long-range mmW link with exceedingly low latency. The EdgeLink™ millimeter wave (mmW) system was deployed as part of the European 5G-Crosshaul H2020 5G-PPP project where an outdoor mesh network was setup in Berlin with link distances up to 185 meters. The inclusion of a self-organizing Mesh topology guarantees failure recovery within the system through redundant paths which are managed by a cloud based software defined network (SDN) controller.