Three-Dimensional Positioning for LTE Systems

In the Third-Generation Partnership Project (3GPP) Long-Term Evolution (LTE) specifications, several 2-D positioning methods have been proposed to support location-based services (LBSs). It has been shown that the observed time difference of arrival (OTDOA) method provides the best result. With the advent of the fifth-generation cellular systems, 3-D beamforming will be introduced, and 2-D positioning may not be sufficient for future applications. Although the conventional OTDOA method can be used in 3-D positioning, it requires more base stations (BSs) in cooperation and often performs poorly in typical cellular network geometry. In this paper, the authors propose a novel OTDOA-based method to solve the problems. First, the authors exploit the sparsity of the wireless channel and propose to use a compressive-sampling-based channel estimation method, which greatly enhances the precision of time-of-arrival (TOA) estimation. Then, the authors propose a transmit beamforming scheme such that the elevation angle of departure (AOD) can be accurately estimated. Finally, the authors combine the estimated TOAs and the AOD in the OTDOA scheme to conduct 3-D positioning. With the proposed scheme, the number of BSs required for 3-D positioning remains the same as that of 2-D, and the positioning accuracy greatly outperforms that of the conventional OTDOA method. Simulations show that 90% of the position error can be less than 7 m.

Language

  • English

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Filing Info

  • Accession Number: 01637650
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jun 1 2017 3:28PM