tailieunhanh - Báo cáo hóa học: " Aspects of Radar Imaging Using Frequency-Stepped Chirp Signals"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Aspects of Radar Imaging Using Frequency-Stepped Chirp Signals | Hindawi Publishing Corporation EURASIP Journal on Applied Signal Processing Volume 2006 Article ID 85823 Pages 1-8 DOI ASP 2006 85823 Aspects of Radar Imaging Using Frequency-Stepped Chirp Signals Qun Zhang1 2 and Ya-Qiu Jin2 1 The Institute of Telecommunication Engineering Air Force Engineering University Xi an Shaanxi 710077 China 2 Key Laboratory of Wave Scattering and Remote Sensing Information Ministry of Education Fudan University Shanghai 200433 China Received 14 September 2005 Revised 19 January 2006 Accepted 15 March 2006 Recommended for Publication by Douglas Williams The high-resolution frequency-stepped chirp signal can be applied to radar systems employing narrow-bandwidth chirp pulses in order to enhance the range resolution and to implement SAR ISAR imaging capabilities. This paper analyzes the effect of moving targets on the synthetic high-resolution range profile obtained using this signal waveform. Some constraints are presented for compensation of the radial motion from shift and amplitude depression of the synthetic range profile. By transmitting two chirp pulses with the same carrier frequency in a pulse-set a method of ground clutter cancellation is designed with respect to this signal format. Finally our simulation data demonstrate the effectiveness of the proposed method. Copyright 2006 Hindawi Publishing Corporation. All rights reserved. 1. INTRODUCTION Radar range resolution is determined by the bandwidth of the transmitted pulse. Classically high range resolution is obtained by either transmitting very short pulses or modulating the pulse to achieve the required bandwidth. Frequencystepping processing is another kind of a very effective method to obtain high downrange profiles of targets such as aircraft and its applicability has been well documented 1 . The main advantage of this approach is that the actual instantaneous bandwidth of radar is quite small compared with the total processing bandwidth. This fact allows the .