Change search
ReferencesLink to record
Permanent link

Direct link
Adaptive Gain Equalizer and Modulation Frequency Domain for Noise Reduction
Blekinge Institute of Technology, School of Engineering.
2010 (English)Independent thesis Advanced level (degree of Master (Two Years))Student thesis
Abstract [en]

Speech quality during the communication is generally e ected by the surrounding noise and interference. To improve the quality of speech signals and to reduce the amount of disturbing noise, speech enhancement is one of the emerging and most used branches of signal processing. For the reduction of noise from speech signals, methods are continuously developed, one method is the Adaptive Gain Equalizer (AGE) which is a single-channel speech enhancement, method that has the particular focus on enhancement of speech instead suppression of noise. Modulation decomposition of the speech signals brought the idea of a modulation system which is useful for modeling of speech and other signals. The purpose of this thesis is to implement the AGE within modulation system, for the purpose of enhancing speech signal, by reducing noise. The successful implementation of the system has been validated with di erent performance measurements, i.e., Signal to Noise Ratio Improvement(SNRI), Mean Opinion Score(MOS), Spectral Distortion(SD). The system has been checked with male and female speaker and with the noise signals Engine Noise(EN), Factory Noise(FN), Gaussian Noise(GN), Tonal Noise(TN) and Impulse Noise(IN) at 0dB, 5dB, 10dB and -5dB Signal to Noise Ratio(SNR). The system has provided the 10dB SNRI for the TN, and around 6dB SNRI for EN and FN. The system has some compromises on the GN and IN in a sense it gives good sound but low SNRI. MOS has been shown between 4 and 3 for all the test cases.

Place, publisher, year, edition, pages
2010. , 87 p.
Keyword [en]
Modulation domain, Adaptive gain equalizer, filter bank, COG, Gain, slow average, fast average
National Category
Signal Processing Probability Theory and Statistics Telecommunications
URN: urn:nbn:se:bth-5074Local ID: diva2:832435
Physics, Chemistry, Mathematics
Available from: 2015-04-22 Created: 2010-06-21 Last updated: 2015-06-30Bibliographically approved

Open Access in DiVA

fulltext(12336 kB)60 downloads
File information
File name FULLTEXT01.pdfFile size 12336 kBChecksum SHA-512
Type fulltextMimetype application/pdf

By organisation
School of Engineering
Signal ProcessingProbability Theory and StatisticsTelecommunications

Search outside of DiVA

GoogleGoogle Scholar
Total: 60 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 40 hits
ReferencesLink to record
Permanent link

Direct link