Assessing the performance of a 60-GHz dense small-cell network deployment from ray-based simulations

Abstract

Abstract-Future dense small-cell networks are one key 5G candidates to offer outdoor high access data rates, especially in millimeter wave (mmWave) frequency bands. At those frequencies, the free space propagation loss and shadowing (from buildings, vegetation or any kind of obstacles) are far stronger than in the traditional radio cellular spectrum. Therefore, the cell range is expected to be limited to 50 -100 meters, and directive high gain antennas are required at least for the base stations. This paper investigates the kind of topology that is required to serve a suburban area with a small-cell network operating at 60 GHz and equipped with beam-steering antennas. A real environment is considered to introduce practical deployment and propagation constraints. The analysis relies on Monte-Carlo system simulations with non-full buffer, and raybased predictions. The ray-tracing techniques are today identified as a relevant solution to capture the main channel properties impacting the beam-steering performance (angular dispersion, inter-link correlation); and the one involved in the present study was specifically enhanced to deal with detailed vegetation modeling. In addition to the user outage, the paper evaluates the evolution of the inter-cell interference along with the user density, and investigates the network behavior in case of local strong obstructions.

Ray-based Deterministic Channel Modelling for sub-THz Band

“…The VolcanoURBAN tool [9] predicts the propagation loss above the clutter based on the well-known knife-edge diffraction technique (including some heuristics). 3D multiple paths are created from a ray-launching process: and the way to manage the vegetation obstacles has been improved [10]. Both the transmission through the vegetation and the diffraction on bottom and top of the foliage are considered.…”

Mixing deterministic and stochastic propagation for assessing mmWave small-cell networks

“…1. It is similar to the one designed in [7] to provide seamless outdoor coverage in absence, but without considering instreet obstacles like bodies or vehicles. The network is composed of 18 small-cells operating at 60 GHz, deployed over a 0.090 km² wide area.…”

“…The present article exploits the ray-based model described in [6] and adjusted to 60 GHz [7] to assess the performance of an outdoor mmWave small-cell network. The model is not used as it was originally.…”

“…The obstruction by a bus was already analyzed in [7], using the same ray-tracing tool. The scenario was composed of two outdoor small-cells and several in-street users.…”

“…The simulation of a dense mmWave outdoor small-cell deployment is reported in section IV. The same study was carried out in [7] with a static propagation environment. It is extended here based on the mixed deterministic and stochastic propagation framework.…”