December 07, 2018

Spatial and Temporal Channel Characteristics of 5G 3D Channel Model with Beamforming for User Mobility Investigations

  • Awada A.
  • Fettweis G.
  • Karabulut U.
  • Simsek M.
  • Viering I.

High carrier frequencies are an integral part of the upcoming fifth generation (5G) mobile networks as they offer high data rates and increase the quality of experience. To compensate for the high path loss at high carrier frequencies, beamforming is applied resulting in users connecting and switching between beams of same or different cells. The current 3D channel models proposed for 5G are complex and have high computational complexity when used in user mobility investigations, which typically require long simulation time for collecting a statistically sufficient number of mobility events. From that perspective, simplified and computationally efficient channel models, that can capture the relevant spatial and temporal correlations, are required for user mobility investigations. To this end, the characteristics of the channel at high carrier frequency are investigated in this paper with respect to fast fading power envelope distribution, temporal variations, and spatial correlations among beams of same cell. Results reveal that for non-line of sight scenario the distribution of fast fading power envelope benefits from diversity gain, and the coherence time remains small even when applying beamforming. Moreover, it has been shown that there is a correlation between the beams of same cell, especially among those that are candidates for serving a user.

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