A pn sequence target detection and processing method based on multi-carrier dtmb signal

Abstract

The invention discloses a PN sequence target detection and processing method based on a multi-carrier DTMB signal. The method comprises the following steps: step (1) carrying out PN mode identification and synchronization calculation on a DTMB signal received by a radar by virtue of a locally known PN sequence, extracting a PN sequence in the DTMB signal, and compensating frequency offset; step (2) carrying out multipath clutter jamming inhibition on the PN sequence processed and obtained in the step (1) by virtue of the locally known PN sequence; step (3) carrying out coherent integration, namely coherence stack and matched filtering on the PN sequence processed in the step (2), and carrying out subsequent processes such as target detection and tracking. By virtue of the method, a target is detected by virtue of a known PN sequence signal, so that an outer-radiation-source radar receiving system does not need to be equipped with an additional reference channel; meanwhile, the algorithms of clutter inhibition and coherent integration are optimized by virtue of the characteristics of the PN sequence signal, so that the calculation amount is reduced, and the detection performance of the target is improved; and the method is easily realized in the engineering, and the feasibility of detecting the target by virtue of the signal is verified by virtue of an actual measurement result.

Description

technical field [0001] The invention belongs to the technical field of radar communication, in particular to a method for detecting and processing a target based on a multi-carrier DTMB signal PN sequence. Background technique [0002] In the past ten years, my country's digital broadcasting has developed rapidly, especially DTMB (Digital Television Terrestrial Multimedia Broadcasting) digital TV terrestrial broadcasting signals have basically covered large, medium and small cities in China. The DTMB standard was proposed in 2006, including two modes of single carrier and multi-carrier. Among them, the multi-carrier mode uses the orthogonal frequency division multiplexing technology to modulate the frame body. Compared with the traditional frequency division multiplexing, this technology improves the spectrum utilization rate and has excellent anti-multipath ability. This mode uses the PN sequence and its cyclic prefix and cyclic suffix as the frame header, which acts as a ...

AI Technical Summary

Problems solved by technology

[0005] For the monitoring of low-altitude near-targets in urban environments (such as UAV detection, target detection in forward scatter areas, etc.) and the existing radar detection methods using digital TV signal sources, it is necessary to purify the reference signal and have a large amount of calculation. The present invention proposes a method for detecting and processing PN sequence targets using multi-carrier DTMB signals. This method does not require additional reference channels, fully utilizes the characteristics of PN sequences and the average power of the signal is twice the average power of the frame body signal, greatly reducing the number of calculations. The amount improves the target detection performance and the system is simpler and easier to implement in engineering. It specifically includes the following steps:

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