전자공학회논문지B (Journal of the Korean Institute of Telematics and Electronics B)
- 제30B권9호
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- Pages.27-35
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- 1993
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- 1016-135X(pISSN)
아날로그 음성 비화기의 비도 및 음질 향상에 관한 연구
A Study on the Improvements of Security and Quality for Analog Speech Scrambler
초록
In this paper, a new algorithm for high level security and quality of speech is proposed. The algorithm is based on the rearrangement of the fast fourier transform (FFT) coefficients with pre and post filter process, hamming window and adaptive pseudo spectrum insertion. Then, the pre and post filters are used for the whitening of speech spectrum and the adaptive pseudo spectrum is inserted for the unclassification of silence/speech. Also, the hamming window technique is applied for the robustness to the syncronization error in the telephone line. According to the simulation results, it can be seen that the security of scrambled signal and the quality of descrambled signal have been improved fairly in both subjective and objective performance test and the new FFT scrambler is robust to the synchronization error.
키워드