To analysis the signal whose frequency changes as time, this article presents a new time-frequency analysis method based on short-time fractional Fourier transform (FRFT) and integration of midpoints. This method uses window functions to divide the signal to many pieces, then the FRFT is used to calculate the frequency modulation (FM) rate of each piece. A chirp signal can be built based on the FM rate and the intermediate frequency (IF) signal is obtained by mixing the chirp signal and the primary signal. The frequency of the midpoints can be estimated by the chirp-z transform (CZT), therefore the frequency of every piece can be calculated. This method avoids the impact that the quick change of frequency leads to the error of short-time Fourier transform. It also can reduce the error brought by the estimation of chirp rate. Therefore, the method can improve the accuracy of time-frequency analysis. This article also puts forward a method to search the order of fractional Fourier transform, and the computer simulation and measurement verifies the effectiveness of the proposed algorithm.
목차
Abstract 1. Introduction 2. Time-Frequency Distribution 2.1 Definition of FRFT 2.2 Calculation of FM Rate 2.3 High Order Moments of FRFT 2.4 Obtain Initial Frequency 2.5 Integration of Midpoints 3. Simulation and Measurement 3.1 Simulation 3.2 Measurement 4. Conclusion References
키워드
fractional Fourier transformintegration of midpointstime-frequency analysis
저자
Wenxin Zhang [ University of Chinese Academy of Sciences, Beijing 100190, China, Key Laboratory of Electromagnetic Radiation and Sensing Technology ,Chinese Academy of Sciences, Beijing 100190, China ]
Xiaojun Liu [ Key Laboratory of Electromagnetic Radiation and Sensing Technology ,Chinese Academy of Sciences, Beijing 100190, China ]
Xiuwei Chen [ Key Laboratory of Electromagnetic Radiation and Sensing Technology ,Chinese Academy of Sciences, Beijing 100190, China ]
Qing Liu [ Key Laboratory of Electromagnetic Radiation and Sensing Technology ,Chinese Academy of Sciences, Beijing 100190, China ]
Guangyou Fang [ Key Laboratory of Electromagnetic Radiation and Sensing Technology ,Chinese Academy of Sciences, Beijing 100190, China ]
보안공학연구지원센터(IJSIP) [Science & Engineering Research Support Center, Republic of Korea(IJSIP)]
설립연도
2006
분야
공학>컴퓨터학
소개
1. 보안공학에 대한 각종 조사 및 연구
2. 보안공학에 대한 응용기술 연구 및 발표
3. 보안공학에 관한 각종 학술 발표회 및 전시회 개최
4. 보안공학 기술의 상호 협조 및 정보교환
5. 보안공학에 관한 표준화 사업 및 규격의 제정
6. 보안공학에 관한 산학연 협동의 증진
7. 국제적 학술 교류 및 기술 협력
8. 보안공학에 관한 논문지 발간
9. 기타 본 회 목적 달성에 필요한 사업
간행물
간행물명
International Journal of Signal Processing, Image Processing and Pattern Recognition
간기
격월간
pISSN
2005-4254
수록기간
2008~2016
십진분류
KDC 505DDC 605
이 권호 내 다른 논문 / International Journal of Signal Processing, Image Processing and Pattern Recognition Vol.8 No.7