数字EMT系统中的多频正交序列解调研究

Multi-frequency Orthogonal Demodulation in Digital EMT System

在正交序列解调技术的基础上提出了一种多频复合解调技术.在理论上,提出并论证了多频解调技术的原理与实现算法,给出了该算法的频域解释;在实验上,基于MATLAB软件和构建的EMT硬件平台,验证了多频解调技术的可行性和准确性.研究结果表明:多频正交序列解调具有更丰富的幅值和相位信息,是一种准确可行的数字解调技术.

Phase sensitive demodulation is a key part of an EMT hardware design. Orthogonal sequential demodulation is the most commonly used digital demodulation at present time. A technique for multi-frequency signal demodulation is put forward based on orthogonal sequential demodulation. Theoretically, the principle and the algorithm of multiple-frequency demodulation is expounded and proved, and the explanation of this algorithm in frequency domain is put forward. Practically, the feasibility and the accuracy of the algorithm is tested based on the MATLAB software and the EMT hardware system. Accordingly, multi-frequency orthogonal sequential demodulation provides more rich information on amplitude and phase, and proves to be an accurate and feasible digital demodulation technology.