Estimation of mistuned frequency from received voice signal in suppressed carrier SSB
Jun Suzuki, Tetsuya Shimamura, Hiroyuki Yashima · 2002
In order to get distortion free speech at suppressed carrier SSB (SCSSB), a receiver should tune to the carrier frequency accurately. Manual tuning is very difficult due to the lack of carrier component. If fine tuning has failed at reception, harmonic structure of demodulated voiced sound is lost. A fundamental frequency Fo, however, can be calculated from the cepstrum of received speech even if the voiced spectrum is shifted. Difference between the carrier frequency and the receiving frequency, is estimated from peaks on the spectrum of received speech, which correspond to harmonics of Fo. Simulation of the proposed method shows that the difference frequency is estimated of accuracy within 4 Hz. This method will contribute to AFC of SCSSB.