Abstract: Described herein is a method that includes storing partial quotients of a continued fraction in a first set of counters, initializing a second sets of counters with counter values, decrementing a target counter in the second set of counters to obtain a decremented counter value, and outputting a value that corresponds to a partial quotient in a first counter in the first set of counters. The value is based on the decremented counter value.

Abstract: The method disclosed consists in analyzing the vocal signals in consecutive windows, in quantifying, on a determined number m of levels, the vocal signal in each of the windows and in measuring, in each of the windows, the vocal signal in each of the windows and in measuring, in each of the windows, the r-m-s value of the samples of the vocal signal. It consists constructing, in a vector space with n dimensions having, as its first base, the unit vectors (E.sub.0 to E.sub.n-1) of the energies measured on n consecutive windows, a resultant energy vector E corresponding to the sum of n energy vectors measured respectively in n windows of analysis of the vocal signal, then in achieving, in this space, a change of base having, as its first main axis, an oriented axis of unit vector having, as its components, the unit vectors of the first base, to project, in the new base obtained, the resultant energy vector. Codings on q bits such that 2.sup.

Abstract: The method disclosed comprises the steps of: cutting up the signal into frames, sampling each frame to obtain a digital signal comprising a determined number n of samples, pre-emphasizing the digital signal, filtering the pre-emphasized digital signal by means of a high-pass digital filter to obtain a filtered digital signal, measuring, in each frame, the maximum energy of the pre-emphasized signal and the maximum energy of the filtered digital signal, to achieve an energy ratio R between the maximum energy of the filtered digital signal and the maximum energy of the pre-emphasized digital signal.

Abstract: The continuous phase angular demodulation method disclosed digitally processes the signal in baseband after having over-sampled it with reference to the bit period. The processing consists in routinely demodulating sub-sets of differential phases at the bit period T.sub.b shifted with respect to one another by fractions T.sub.b /q of this period, in correcting them, a priori, by the phase deviations associated with a set of pre-defined d frequency drifts and in computing, for the d.q sets thus obtained, a noise criterion. The set of demodulated bits chosen is the one that reduces this noise criterion to the minimum. The set of bits then enables computation of the phase variation emitted and, using this variation and the measured variation, the real frequency drift. Another demodulation taking this drift into account is done for the q sets of initial differential stages and the set minimizing the noise criterion is then chosen and fixes the synchronization bit by the sampling instants associated with it.

Abstract: A method and device are provided for multistate modulation and demodulation with adjustable protection level, consisting in separating the binary signals, before demodulation, into critical and non critical signals, in attributing to the non critical signals all the states of the modulation and in attributing to the critical signals a reduced number of states which are, in the modulation diagram, the furthest removed from each other.

Abstract: The symbol synchronization method for the symbol demodulation of a digital signal uses E sequences of samples taken from the demodulated signal, each sequence being offset with respect to the following one by a fraction of the symbol period Ts/E. On the basis of each one of E sequences of samples (Si1,Si2, . . . SiN) ranging from from i=0 to E-1, a value F(i) of a pre-defined function F, optimized according to the type of modulation made at emission, is calculated. This function, which can be identified with a sine model, A+B COS(i-io)2.pi./E, can be used to determine io characteristic of the synchronization time-shift and, if necessary, A, characteristic of the d.c. offset, and B, characteristic of the variation in levels due to reception conditions. These values are used to correct the synchronization signal and, if necessary, the d.c. and the decision thresholds of the decision circuit during the symbol demodulation.