Detection of LFM signals in low SNR based on STFT and wavelet denoising

Author

Duan Yu ; Wang Jinzhen ; Su Shaoying ; Chen Zengping

Author_Institution

ATR Key Lab., Nat. Univ. of Defense Technol., Changsha, China

fYear

2014

fDate

7-9 July 2014

Firstpage

921

Lastpage

925

Abstract

In view of continuous time-frequency characteristic of linear frequency modulated (LFM) signals, a detection method based on Short-time Fourier transform (STFT) and wavelet denoising is proposed. Input signals are short-time Fourier transformed into coherent integration of frequency-shift sample sequences with complex envelopes, achieving a time-frequency curve which is to be processed by wavelet, in order to weaken the noise and to detect LFM signals effectively. The scheme remains available in quite a low signal-to-noise (SNR) with low complexity. Simulation results show its fine detection performance in -18dB condition, which meets the demand of electronic reconnaissance to a large extent.

Keywords

Fourier transforms; frequency modulation; sequences; signal denoising; signal detection; time-frequency analysis; wavelet transforms; LFM signal detection method; STFT; complex envelopes; continuous time-frequency characteristic; electronic reconnaissance; frequency-shift sample sequence coherent integration; input signals; linear frequency modulated signals; low SNR; low signal-to-noise; short-time Fourier transform; time-frequency curve; wavelet denoising; Noise reduction; Signal to noise ratio; Time-frequency analysis; Wavelet transforms; DSP; LFM; STFT; low SNR; wavelet;

fLanguage

English

Publisher

ieee

Conference_Titel

Audio, Language and Image Processing (ICALIP), 2014 International Conference on

Conference_Location

Shanghai

Print_ISBN

978-1-4799-3902-2

Type

conf

DOI

10.1109/ICALIP.2014.7009929

Filename

7009929