FIELD: communication means.
SUBSTANCE: invention pertains to wireless digital communication making use of speech coding and, in particular to the system and method of detection of bad data frames in reception of speech transfers. System and method of indication of faulty speech data frame includes evaluation of the signal/noise (SNR) ratio and checking value of the cyclic redundancy code (CRC) of the speech data frame. When speech data frame fails to go through the error check successfully by means of CRC, or SNR is lower than preliminary set value, bad frame indicator flag (BFI) is set. When the speech data frame goes through the error check by means of CRC successfully, and SNR is above the set value, quality metric of the received signal of the speech frame is checked against the upper threshold, and if necessary, against the low threshold. BFI flag and quality metric of the received signal for the previous speech frame is checked when the current quality metric of the received signal is between the upper and low thresholds. BFI flag is set according to the SNR value, CRC index, current and preceding quality metrics of the received signals and preceding BFI flag.
EFFECT: secured identification of bad frames, blocking negligible number of good speech frames, when a good signal is received.
31 cl, 4 dwg
