Method and device for frame loss concealment

The lost frame concealment method, modified discrete cosine transform (MDCT: Modified Discrete Cosine Transform) if the count is detected to be lost, the lost frame previous record signal corresponding to the MDCT coefficient to generate a first synthesized signal (history signal) steps to use; The inverse modified discrete cosine transform coefficient corresponding to the lost MDCT (IMDCT: Inverse Modified Discrete Cosine Transform) performing a fast IMDCT for the first synthesized signal to obtain coefficients; And time-domain aliasing by using the IMDCT coefficient adjacent to the IMDCT coefficient corresponding to the IMDCT coefficient, and the lost MDCT coefficient corresponding to the lost MDCT coefficient (TDAC: Time Domain Aliasing Cancellation) to perform, and the lost frame and a step of obtaining a signal corresponding to. Also discloses apparatus for concealing lost frame. A method and apparatus for concealing a lost frame in an embodiment of the present invention by using the received partial signal to completely restore the quality of the speech signal and to improve the QoS.