A clutter suppression method for urban building environment based on wifi passive radar

Abstract

The invention discloses a method for suppressing urban building environment clutter by WiFi passive radar. On the basis of external radiation source radar signal processing, a preparatory work stage is added. In the preparatory work stage, the task of the radar is not to monitor or detect targets, but to collect building clutter echoes returned from the surrounding fixed environment, and to establish building environment clutter echoes. wave database; in the normal working phase, the radar is in the monitoring or target detection working state, for the monitoring channel signal, the primary clutter suppression processing and cross-correlation operation are performed first, and then the building clutter data stored in the building environment clutter database is used to The residual building clutter in the surveillance signal after cross-correlation processing is cancelled, and then the target is detected; the signal-to-clutter ratio after processing can be significantly improved.

Description

Technical field [0001] The invention belongs to the field of passive radar clutter suppression, and particularly relates to a WiFi passive radar clutter suppression technology using a clutter database of urban construction environment. Background technique [0002] WiFi passive radar uses WiFi signals that are easily available in urban space as an external radiation source, which can detect, locate and track interesting targets existing in buildings or in surrounding areas, and can be applied to security and scenes Surveillance, autonomous driving, clearing of important places, identification of dangerous targets, and emergency situation awareness are a kind of intelligent sensors with great application prospects. However, the complex building environment will cause the reflection, scattering and diffraction of electromagnetic waves, and cause serious environmental clutter interference to the passive radar system, which has become the fundamental reason for limiting the detection...

AI Technical Summary

Problems solved by technology

The airspace suppression method is spatial filtering, which requires the system to adopt an array antenna configuration, which is complex and costly to implement; the time domain suppression method needs to generate reference echo signals corresponding to the delay of different distance units, and calculate the projection matrix to project the monitoring signal to the clutter Orthogonal subspaces, but there is a problem of large amount of calculation, such as the extended cancellation algorithm (ECA, Ex-tensive Cancellation Algorithm) proposed by F.Colone, University of Rome, Italy, and the segmented extended cancellation algorithm (ECA-B, Extensive Cancellation Algorithm Batches) etc.

In addition, the above environmental clutter suppression method does not make full use of the prior information of the fixed building echo contained in the environmental clutter, and there is still the problem of insufficient suppression of the building environment clutter

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