Experimental Analysis of Dense Multipath Components in an Industrial Environment

Abstract

Abstract-This work presents an analysis of Dense MultipathComponents (DMC) in an industrial workshop. Radio channel sounding was performed with a vector network analyzer and virtual antenna arrays. The specular and dense multipath components were estimated with the RiMAX algorithm. The DMC covariance structure of the RiMAX data model was validated. Two DMC parameters were studied: the distribution of radio channel power between specular and dense multipath, and the DMC reverberation time. The DMC power accounted for 23 to 70% of the total channel power. A significant difference between DMC powers in line-of-sight and non-line-of-sight was observed, which can be largely attributed to the power of the line-of-sight multipath component. In agreement with room electromagnetics theory, the DMC reverberation time was found to be nearly constant. Overall, DMC in the industrial workshop is more important than in office environments: it occupies a fraction of the total channel power that is 4 to 13% larger. The industrial environment absorbs on average 29% of the electromagnetic energy compared to 45-51% for office environments in literature: this results in a larger reverberation time in the former environment. These findings are explained by the highly cluttered and metallic nature of the workshop.

Polarimetric Distance-Dependent Models For Large Hall Scenarios

“…The dense multipath field is modeled as uncorrelated in the spatial (angular) domains (I MR and I MT ) but correlated in the frequency (timedelay) domain (R f ). The isotropy assumption in the angular domain implies that the DMC should be antenna independent as demonstrated in [14]. Originally, the DMC is estimated from the covariance matrix of the complete data model (i.e.…”

“…In those models, the DMC is typically observed as the decaying slope of the power delay profile (PDP) [12] and characterized by its reverberation time [8]. It was shown that the energetic contribution of the DMC to the radio channel can vary between 20% and 80% for indoor or industrial scenarios [2], [13], [14], [15]. A distance-dependent model was recently reported for indoor radio channels where the PDP is described as the sum of the early SMC part of the PDP and reverberant component [16].…”

Capacity analysis of an IEEE 802.11n system in a residential house based on estimated specular and dense multipath components

“…Furthermore, the reliability of each estimated SMC is checked with a criterion based on the SMC power estimate and its estimation error variance (see [2] and [8] for further details). Estimated SMCs that fail this criterion are removed from further analysis.…”

“…This is expected as increased shadowing means that a larger proportion of the radio channel power will be carried by the DMC. Shadowing of the SMC reduces their power to the point where the RiMAX estimator cannot reliably detect them among the scattered diffuse multipath [8]. In this case, these low-power SMC are automatically lumped together with the DMC, increasing the presence and the power of the latter.…”

Capacity simulation and analysis of an IEEE 802.11n system in a residential house

“…Subsequently, the DMC and noise, i.e., the measured channel minus all optimized SMCs, are fitted to the data model in (3) and (4). Furthermore, the reliability of each estimated SMC is checked against a criterion based on the SMC power estimate and its estimation error variance (see [1] and [5] for details). If all five SMCs in one RiMAX iteration fail the reliability criterion, then the algorithm is stopped.…”