Speech Enhancement

This thesis presents algorithm and architecture for§simultaneous diagonalization of matrices. As an§example, a subspace-based speech enhancement problem§is considered, where in the covariance matrices of§the speech and noise are diagonalized simultaneously.§In order to compare the system performance of the§proposed algorithm, objective measurements of speech§enhancement is shown in terms of the signal to noise§ratio and mean bark spectral distortion at various§noise levels. In addition, an innovative subband§analysis technique for subspace-based time-domain§constrained speech enhancement technique is proposed.§The proposed technique analyses the signal in its§subbands to build accurate estimates of the§covariance matrices of speech and noise, exploiting§the inherent low varying characteristics of speech§and noise signals in narrow bands. The subband§approach also decreases the computation time by§reducing the order of the matrices to be§simultaneously diagonalized. Further, architecture is§proposed to implement the simultaneous§diagonalization scheme. The architecture is§implemented on a Xilinx FPGA. FPGA resource§utilization re-enforces on the practicability of the§design.