Abstract: Method of preparing data, in particular voice signal parameters for transmission at a low bit rate, identical signal parameters are combined interval by interval in quantized form; forfurther bit reduction, bits are suppressed from the total number of bits of at least two intervals, the bit difference to be suppressed being formed on the basis of the total number of unreduced bits with respect to the next-higher power of two; and theprocedure supplies a better voice quality than in the case of changing the number of quantization stages by multiples of 2.

Abstract: The vector encoding method, particularly for voice signals, includes storing autocorrelation coefficients in one codebook and performing a logic operation on the autocorrelation coefficients with an autocorrelation function for the pulse response of an excitation filter to give the energy of the filtered excitation signal. For additional data reduction only those values having three autocorrelation coefficients other than the value 0 are entered in the codebook. The combination patterns which can be formed from these coefficients occur with the same frequency in the codebook. Because of these features, a transmission of encoded data which is very robust with respect to faults is possible with reduced processing and storage effort.