Ray Tracing RF Field Prediction: An Unforgiving Validation

Abstract

The prediction of RF coverage in urban environments is now commonly considered a solved problem with tens of models proposed in the literature showing good performance against measurements. Among these, ray tracing is regarded as one of the most accurate ones available. In the present work, however, we show that a great deal of work is still needed to make ray tracing really unleash its potential in practical use. A very extensive validation of a state-of-the-art 3D ray tracing model is carried out through comparison with measurements in one of the most challenging environments: the city of San Francisco. Although the comparison is based on RF cellular coverage at 850 and 1900 MHz, a widely studied territory, very relevant sources of error and inaccuracy are identified in several cases along with possible solutions.

Comparison of Empirical and Ray-Tracing Models for Mobile Communication Systems at 2.6 GHz

“…The ray-tracing model was expected to outperform the empirical models, even considering a substantial lack of detail in the model. However, as also documented by [8], ray-tracing requires much detail for accurate predictions of received power.…”

“…Maintaining and obtaining such geographical data is considered complex and time-consuming, however, when such data is obtained, modelling for new frequencies is trivial. [8] For these reasons, ray-tracing is commonly used for detailed propagation planning and link-level simulations, and usually cases where deployments already are present.…”

Measuring the non-line-of-sight ultra-high-frequency channel in mountainous terrain : a spread-spectrum, portable channel sounder

“…Geospatial analysis appears to be a useful method of channel characterization in mountainous terrain where large spatial scales and rough reflecting surfaces (i.e., sub-λ to tens of meters in scale) make computational approaches burdensome. Ray-tracing models might provide a valuable comparison to the experimental work presented herein (Vitucci et al 2015). However, we note that ray tracing generally applies to geometries with dimensions that are much greater than the signal wavelength; and thus, surface roughness effects would likely be lost by ray-tracing analysis.…”

Collaborative Quality Framework: QoE-Centric Service Operation in Collaboration with Users, Service Providers, and Network Operators

“…It has been reported that the radio propagation simulation provides very close estimates of the actual radio transmission measurement results, such as received field strength [22]. However, if we assume crowd-sourcing data collection, we need to investigate the stability of radio transmission measurement, such as RSRP, when measured under realistic usage conditions of smartphones.…”