Oversampling D/A Converter Design for Improved Signal to Quantization Noise Ratio

International Journal of Computer Trends and Technology (IJCTT)          
© 2015 by IJCTT Journal
Volume-28 Number-4
Year of Publication : 2015
Authors : Himanshu Mahatma, Rajesh Mehra, Gyan Prakash Pal


Himanshu Mahatma, Rajesh Mehra, Gyan Prakash Pal "Oversampling D/A Converter Design for Improved Signal to Quantization Noise Ratio". International Journal of Computer Trends and Technology (IJCTT) V28(4):167-171, October 2015. ISSN:2231-2803. www.ijcttjournal.org. Published by Seventh Sense Research Group.

Abstract -
Signals dealt in real world are mostly analog in nature and are needed to convert them in digital format before processing; finally when these signals are again represented to real world a reverse conversion is necessary. The accuracy of this conversion is dependent on number of bits used and/or number of samples taken during conversion, the error between the original signal and reconstructed signal represents a noise called quantization noise. This noise can be reduced if the numbers of samples are increased. The oversampling technique is used to increase the number of samples, which reduces the spacing between the samples so the accuracy of the output is improved and SNR is increased. To further improve the performance of D/A converter, sigma delta modulator with one bit quantization level is used to decrease word length while maintaining good resolution. In this paper, some examples are used to show D/A conversion with improved SQNR by using oversampling technique.

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oversampling, D/A converter, sigma delta modulator, multirate signal processing, single-bit quantization, multi-bit quantization.