Companding techniques for high dynamic range audio CODEC receiver path

In this thesis, an audio CODEC receiver path has been modified by the addition of companding techniques. Companding compresses the input signal and expands the output signal according to the input power strength such that additional noise from the system is suppressed while the signal content is maintained. As the compression level is varied according to the input signal strength, transients occur at the output of the system. Sudden changes in the compression level cannot be processed instantaneously and generate transients in the output. The thesis first statically demonstrates that companding can increase the signal to noise ratio and improve the dynamic range of the audio CODEC Rx path by up to 18 dB. Further, two compensation techniques are analyzed in attempt to reduce the companding transients. The results show that transients in the output are reduced on average by 60% when using either compensation technique.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Ma, Yunjie, M. Eng. Massachusetts Institute of Technology

Advisor dc:contributor.advisor

• Guoqing Miao and Vladimir Stojanovic.

• Electrical Engineering and Computer Science.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/53133

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/53133