Direct wave AOA determination method in indoor multipath environment

Abstract

The invention discloses a direct wave AOA (Angle of Arrival) determination method in an indoor multipath environment. The direct wave AOA determination method in an indoor multipath environment includes the steps: 1) a sending terminal is equipped with a plurality of antennas to send signals, and a receiving terminal can estimate the channel state information between each sending antenna and the receiving terminal after receiving the signals; 2) according to the channel state information, the AOA-TOF (Time of Flight) estimate of each path in a propagation path cluster of each sending antenna and the receiving terminal is obtained; 3) a threshold is set, and one path cluster among the plurality of path clusters is selected at will as the initial path cluster; 4) the path in the initial pathcluster is selected and the path is determined, and according to the determination result, a decision is made for determining whether or not to maintain the path or remove the path; 5) each path in the initial path cluster is traversed, and the finally obtained path cluster is the maintained path cluster of the initial path cluster; and 6) according to the path situation in the maintained path cluster, the estimate of the direct wave AOA is output. The direct wave AOA determination method in an indoor multipath environment has the advantages of high determination accuracy for the direct waveAOA in the indoor multipath environment, low computational complexity, high timeliness, and no requirements for participation of users.

Description

technical field [0001] The invention relates to the field of wireless indoor positioning, in particular to a direct wave AOA determination method in an indoor multipath environment. Background technique [0002] With the popularity of mobile devices and the development of mobile Internet, positioning has become one of the important modules in many mobile applications. However, accurate indoor positioning is still a key missing part of the mobile Internet at this stage, and how to obtain accurate location information indoors has become a research hotspot in the academic circles. [0003] Compared with the current indoor positioning technology based on fingerprints, the positioning technology based on AOA (Angle of Arrival, angle of arrival) has gained widespread attention because it does not need to spend manpower and material resources to build a fingerprint database. In recent years, some commercial Wi-Fi devices such as Intel 5300 and Atheros 9380 have successfully obtain...

AI Technical Summary

Problems solved by technology

[0004] In the prior art, the CUPID system judges the AOA with the largest peak in the MUSIC spectrum as the AOA of the direct wave, but in the real environment, due to people moving around to block the propagation signal and hardware imperfections, the peak in the MUSIC spectrum with the largest peak is not necessarily corresponding to the direct wave

The LTEye system judges the path with the minimum estimated value of TOF (Time of Flight) as the direct arrival wave, but to estimate a relatively accurate TOF requires high-precision communication equipment, and current commercial communication equipment generally does not meet this standard. TOF The estimated value often has a large error, so the method proposed by the system cannot be well used in practice

The SpotFi system uses the results of multiple AOA estimates to determine the cluster with the smallest variance as the cluster corresponding to the direct wave through the clustering method, and the AOA average value of the elements in the cluster is used as the estimate of the AOA of the direct wave. The method works well, but the computational complexity is high, which cannot meet the real-time positioning requirements

The ArrayTrack system requires user participation when determining the direct wave AOA, and requires mobile sending equipment, which is difficult to apply in a large number of stationary equipment positioning scenarios

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