V.Yu.Semenov The new method of line spectral frequencies calculation based on the universal algorithm of solution of transcendental equations |
Acoustic bulletin, Vol. 5 ¹ 4, (2002) |
| The new efficient method of calculation of the line spectral frequencies (LSF) is proposed. The method is based on a developed algorithm of full numerical solution of transcendental equation having no multiple roots. This algorithm is composed of two parts - location of intervals containing a single root and folowing refinement of root's value by one of standard rootfinding procedures. Efficiency of different modifications of the proposed LSF calculation method is verified on real speech signals. Two approaches to computation of LSF are considered - the direct solution of transcendental equations containing trigonometric functions and the solution of polynomial equations obtained by the series expansion in Chebyshev polynomials. The LSF's ordering property is used for decreasing the computational expenses. In opposite to majority of existing LSF computation algorithms, the proposed method provides arbitrary high accuracy and guarantees the stability of a corresponding autoregressive filter. It is shown that the developed method can be applied in real-time processing systems. |
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KEY WORDS: speech signal, line spectral frequency, autoregressive filter, digital communications system |
| TEXT LANGUAGE: Russian |