TAN Xiao-yun, ZHOU Xian-zhong, JIANG Yi-ming, et al. Comparative analysis of Sigma Delta modulation and pulse code modulation in micro-accelerometer[J]. Optics and precision engineering, 2009, 17(6): 1228-1232.
TAN Xiao-yun, ZHOU Xian-zhong, JIANG Yi-ming, et al. Comparative analysis of Sigma Delta modulation and pulse code modulation in micro-accelerometer[J]. Optics and precision engineering, 2009, 17(6): 1228-1232.DOI:
A comparative study of the Sigma Delta Modulation(SDM) and the Pulse Code Modulation(PCM) is presented
and the advantages and the disadvantages of the two kinds of modulation are also obtained. A 2-bit SDM simulated system and a 2-bit (PCM) simulated system for a micro-accelerometer are established in this paper. Then
the accelaration signals pass through the modulations are comparatively analyzed
and the difference of two mudulations output waves is obtained by the comparive analysis. Finally
the power spectral density patterns of two kinds of the modulated signals are computed with a periodogram respectively. The power spectral density from experimental results indicates that the quantization noise of the PCM is more serious than that of the SDM in the low frequency
but the quantization noises of both modulation methods are the same in the high frequency. The simulated results show that the SNR of the SDM is 20 dB higher than that of the PCM
though the SDM modulation system is more complex than the PCM.