GSM Speech Coder Indirect Identification Algorithm

This paper presents GSM speech coder indirect identification algorithm based on sending novel identification pilot signals through the GSM speech channel. Each GSM subsystem disturbs identification pilot, while speech coder uniquely changes the tempo-spectral characteristics of the proposed pilot signal. Speech coder identification algorithm identifies speech coder with the usage of robust linear frequency cepstral coefficient (LFCC) feature extraction procedure and fast artificial neural networks. First step of speech coder identification algorithm is the exact position detection of the identification pilot signal using normalized cross correlation approach. Next stage is time-domain windowing of the input signal to convolve each frame of the input speech signal and window spectrum. Consecutive step is a short-time Fast Fourier Transformation to produce the magnitude spectrum of each windowed frame. Further, a noise reduction with spectral subtraction based on spectral smoothing is ca...

• Type: Journal
• Year: 2010
• Where: INFORMATICALT
• Authors: Rajko Svecko, Bojan Kotnik, Amor Chowdhury, Zdenko Mezgec
• Keywords: Coder Identification, Communications, GSM Speech Coder, INFORMATICALT 2010, Speech Coder