Waveform design of double-period pinch-off pseudo-random code and signal processing method for echo

Abstract

The invention relates to a waveform design for a double-cycle pinch-off type pseudo-random code and a signal processing method for an echo. The waveform design for the double-cycle pinch-off type pseudo-random code and the signal processing method for the echo is characterized in that the needed radar signal-transmitting time width is computed combined with a radar equation, codon time width of random codes of a first group, the digit of the random codes and subcode time width when a wave form is pinched off are ascertained. An echo signal after analogue-to-digital sampling is finished under despreading and spread spectrum and section matched filtering is carried out. The result of the section matched filtering is under fast fourier transform (FFT) treatment, the constant false alarm rate (CFAR) technology is utilized, and a target is detected in a velocity dimension and a distance dimension. The waveform parameters of random codes of a second group are ascertained to cover a dead zone. Target data obtained through the first group and the second group are mixed to discover and complement the dead zone. The waveform design for the double-cycle pinch-off type pseudo-random code and the signal processing method for the echo has the advantages of being short in instantaneous pulse width and high in waveform duty ratio, short in distance of the dead zone, small in transmitting power and time sharing in receiving and dispatching.

Description

technical field [0001] The invention belongs to the field of waveform design and signal processing of radar (or its similar active emission sensors), and specifically relates to a waveform design of a double-period pinch-off pseudo-random code and a signal processing method for echo. Background technique [0002] Traditional radar can be divided into continuous wave radar and pulse radar according to the time period of the transmitted waveform. While the continuous wave radar emits electromagnetic waves, the receiver receives the echo signal and performs signal processing. When the pulse radar emits electromagnetic waves, the radar receiver is turned off, and the echo signal is collected after the emission cycle ends. [0003] The advantage of continuous wave radar is that the radar distance blind zone is short, but it has the problem of transmission and reception leakage. The leakage of the transmitted signal to the receiver can easily cause the saturation of the receiver...

AI Technical Summary

Problems solved by technology

[0007] In order to avoid the deficiencies of the prior art, the present invention proposes a waveform design of a double-period pinch-off pseudo-random code and a signal processing method for the echo, which solves the problem of leakage of transmission and reception of continuous wave radar, and the large distance of pulse radar blind spot problem

Images