Real-time Signal Processing Algorithms

ISBN-13: 9783639140705 / Angielski / Miękka / 2009 / 96 str.

Rohith Ramachandran

Opis

Cochlear implant (CI) patients have difficultyunderstanding tonal languages which use pitchvariations to convey meaning because of poor pitchperception. The ability of CI patients to communicatein noisy environments is severely degraded.Therefore, pitch-detection and (spatial) noisesuppression is of importance to current cochlearimplant devices. This thesis provides the details ofreal-time implementations that address theseconcerns. A pitch-detector was implemented toestimate the pitch and a beamformer was implementedto suppress spatial noise. The pitch-detection andthe beamforming algorithms were implemented on an ARMbased processor of a Personal Digital Assistant(PDA). The pitch-detection algorithm is based on theautocorrelation function. Its real-time performancewas measured and its efficiency in the presence ofspeech-shaped noise and babble noise was evaluated.The beamforming algorithm implemented was theGriffiths beamformer. Objective and subjective testsfor different signal-to-noise ratio levels ofspeech-shaped noise were conducted to evaluate itsperformance. This thesis includes the results ofthese evaluations.

O autorze

Rohith Ramachandran was born in Bangalore,India. He entered M. S
Ramaiah Institute of Technology, Bangalore in October 2000,to
pursue his Bachelor's degree in Electronics and Communications
Engineering. From August 2006, he has been a student in The
University of Texas at Dallas to pursue his Master of Science
degree in Electrical Engineering.