Study and Design of Precision Enhancement of Multiple Targets in FMCW Systems

Autor: Ming-Yi Ling, 林明毅
Rok vydání: 2016
Druh dokumentu: 學位論文 ; thesis
Popis: 105
This thesis analyzes and investigates the principles of frequency modulation continuous wave (FMCW) radar, and develops an algorithm to enhance the accuracy of range, as well as designs the digital signal processing circuits, including Fast Fourier transform (FFT) and inverse FFT, waveform correction, spectrum separation and so on. Firstly, the basic structure and working principles of FMCW radar ranging system are introduced. The triangular wave modulation signals are analyzed in details. The ranging errors of FMCW radar are affected by the accuracy of FFT spectrum estimation owing to the hurdle effect and spectrum leakage of FFT process. For the demand of high precision, short length of the FFT spectrum estimation is not accurate enough. In this thesis, the reasons that influence the ranging accuracy of FMCW radar are analyzed, and a new approach is proposed by combining the waveform correction algorithm and FFT to enhance the ranging precision of FMCW radar system. The Matlab simulation results confirm this algorithm can improve the ranging precision of multiple targets. Field programmable gate array (FPGA) was selected as the hardware development platform. After the FMCW radar analog baseband signals are sampled by the analog-to-digital converter (ADC) controller, the sampled data are transferred to the computer. The distances of the targets are obtained using the waveform correction and FFT algorithm. This algorithm was implemented using FPGA by the Xilinx Virtex7 VCVX330T platform and operated at 120 MHz. The measurement results were successfully verified with those from Matlab simulations.
Databáze: Networked Digital Library of Theses & Dissertations