Patent · US Expired

Method distinguishing line of sight (LOS) from non-line of sight (NLOS) in CDMA mobile communication system

US7099640B2 · kind B2 · utility

3Cited by
2References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 29, 2002
Grant dateAug 29, 2006
Priority date
Expiry dateMay 2, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/7113
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The invention discloses a method that identifies whether a channel is LOS or NLOS in a mobile communication system. After coherent accumulation and non-coherent accumulation have been made by the system, first the method takes power difference between the direct path and the non-direct path in a same power delay profile to identify a channel; and then the result is further determined by {overscore (τ)}/σ difference of a LOS channel and a NLOS channel (where {overscore (τ)} and σ is the mean delay and the RMS delay spread of a multipath power profile, respectively). A channel is determined as a LOS channel, if the power ratio of the Maximum Path to the Local Maximum Path is greater than a threshold K, and simultaneously the arrival time difference between the First Path and said Maximum Path is less than a time interval T; otherwise it is a NLOS channel. The method is easier to implement and compatible with the present mobile communication system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.