Amplitude and Phase Analysis Based on Signed Demodulation for AM-FM Signal

Guanlei Xu, Xiaotong Wang, Xiaogang Xu, Limin Shao

Navigation Department, Dalian Navy Academy, Dalian, China.
Ocean Department, Dalian Navy Academy, Dalian, China.

DOI: 10.4236/jcc.2014.29012                

Abstract

This paper proposes a new amplitude and phase demodulation scheme different from the traditional method for AM-FM signals. The traditional amplitude demodulation assumes that the amplitude should be non-negative, and the phase is obtained under the case of non-negative amplitude, which approximates the true amplitude and phase but distorts the true amplitude and phase in some cases. In this paper we assume that the amplitude is signed (zero, positive or negative), and the phase is obtained under the case of signed amplitude by optimization, as is called signed demodulation. The main merit of the signed demodulation lies in the revelation of senseful physi- cal meaning on phase and frequency. Experiments on the real-world data show the efficiency of the method.

Keywords

Amplitude Demodulation, Phase, Hilbert Transform, Signed Demodulation

Conflicts of Interest

The authors declare no conflicts of interest.

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