DYNAMIKKOMPRESSOR

摘要

The invention relates to a sub-band splitter unit for splitting a broadband input signal (G1), e.g., an audio signal, in K narrowband sub-band signals (L1,....., Lk,....., LK), wherein K is an integer larger than 1, which sub-band splitter unit (100) is provided with an input terminal (100) for receiving the broadband input signal and K-1 sub-band filter circuits (SBF1,....., SBFk,....., SBFK-1), each of the sub-band filter circuits (SBFk) is provided with an input (103.k) and a first (104.k) and a second output (105.k), a first filter arrangement (LPFk) coupled between the input (103.k) and the first output (104.k), a second filter arrangement (HPFk) coupled between the input (103.k) and the second output (105.k), and the sub-band splitter unit is provided with K output terminals (102.1,....., 102.k,....., 102.K) for supplying the K sub-band signals. The first output (104.k) of a k-th sub-band filter circuit (SBFk) is coupled to an input (103.k+1) of the (k+1)-th sub-band filter circuit. The input (103.1) of the first sub-band filter circuit (SBF1) is coupled to the input (101) of the sub-band splitter unit. The second output (105.k) of a k-th sub-band filter circuit is coupled to the k-th output (102.k) of the sub-band splitter unit. The first output (104.K-1) of the (K-1)-th sub-band filter circuit is coupled to the K-th output (104.K-1) of the sub-band splitter unit. The first filter arrangement (LPFk) of a sub-band filter circuit is adapted to carry out a lowpass filtering on the signal at the input of the first filter arrangement, and the second filter arrangement (HPFk) is adapted to carry out a highpass filtering on the signal at the input of the second filter arrangement. In addition, the sub-band splitter unit is furthermore devoid of any down-sampling means. (Fig.1). Furthermore, the invention relates to a sub-band combining unit (110), for which holds that it is provided with K input terminals (111.1,....., 1111.k,....., 111.K) for receiving the K narrowband sub-band signals and an output terminal (112). The sub-band combining unit is adapted for combining the K narrowband sub-band signals for generating a broadband output signal which is a replica of the broadband input signal of the sub-band splitter unit, and for supplying the broadband output signal to its output terminal. The sub-band combining unit is adapted to add time equivalent samples of the K narrowband sub-band signals to generate the broadband output signal. Thereby, the subband combining unit is devoid of any up-sampling means (Fig.1,2). Further, the invention proposes an envelope curves detector unit, wherein the envelope curves detector unit comprises the K-1 sub-band filter circuits of the sub-band splitter unit.