Measurement-based LoS/NLoS channel modeling for hot-spot urban scenarios in UMTS networks

Abstract

In this contribution, a measurement campaign is introduced for modeling radio channels with either Line-of-Sight (LoS) or Non-Line-of-Sight (NLoS) connection between a user equipment (UE) and a NodeB (NB) in an operating Universal Mobile Telecommunications System. A Space-Alternating Generalized Expectation-maximization (SAGE) algorithm is applied to estimate the delays and the complex attenuations of multipath components from the obtained channel impulse responses. Based on a novel LoS detection method of multipath parameter estimates, channels are classified into LoS and NLoS categories. Deterministic models which are named “channel maps” and fading statistical models have been constructed for LoS and NLoS, respectively. In addition, statistics of new parameters, such as the distance between the NB and the UE in LoS/NLoS scenarios, the life-distance of LoS channel, the LoS existence probability per location and per NB, the power variation at LoS to NLoS transition and vice versa, as well as the transition duration, are extracted. These models are applicable for designing and performance evaluation of transmission techniques or systems used by distinguishing the LoS and NLoS channels.