Channel inconsistency error correction direction finding method for channel state information

Abstract

The invention discloses a channel inconsistency error correction direction finding method for channel state information, and belongs to the technical field of indoor positioning. The method comprisesthe following steps: modeling a CSI direction finding algorithm; calculating direct wave time of flight ToF by using the single antenna data; smoothing the CSI data between the paired antennas to increase the aperture of the receiving array; carrying out amplitude-phase error calculation between paired antennas by using the direct wave time of flight ToF and the direct wave incident angle prior information; and establishing an amplitude-phase error table under different incoming wave directions according to offline data, dynamically selecting a gamma value according to the table in an online process, and performing channel amplitude-phase error correction and iterative direction finding. According to the invention, a complex inter-channel amplitude-phase error correction problem of a commercial Wi-Fi network card is solved; the CSI direction finding precision of the Wi-Fi network card is ensured, the complexity and cost of deployment and use of the indoor positioning system based on the commercial Wi-Fi network card are effectively reduced, the application prospect is wide, the operation is simple, special equipment is not needed, and the method can effectively adapt to an indoor multipath environment.

Description

technical field [0001] The invention belongs to the technical field of indoor positioning, and in particular relates to a direction finding method for channel inconsistency error correction of channel state information. Background technique [0002] Traditional indoor positioning algorithms based on wireless signal strength are often difficult to obtain the required positioning accuracy due to factors such as multipath effects in the indoor environment. The current indoor positioning method using channel state information (Channel State Information, CSI) direction finding is considered to be an effective way to improve positioning accuracy. CSI is a fine-grained description of different subcarriers in the channel state, which can better reflect the multipath state of the channel. However, the CSI direction-finding accuracy of common commercial Wi-Fi network cards is limited by the amplitude and phase errors caused by the inconsistency of multi-antenna receiving channels. A...

AI Technical Summary

Problems solved by technology

However, the CSI direction-finding accuracy of common commercial Wi-Fi network cards is limited by the amplitude and phase errors caused by the inconsistency of multi-antenna receiving channels.

At present, the traditional channel inconsistency error correction method cannot solve the problem of indoor multipath effect, and the correction accuracy is limited; while using special equipment such as a vector network analyzer for wired correction or directly using a specially designed high-precision network card, the operation is complicated or hardware High cost, difficult to promote and apply on a large scale

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