Abstract: The voice quality of telephone calls is evaluated. A first connection is established between a computerized apparatus and a person acting as a first experimenter, and a second connection is established between the platform and a second experimenter. The first and second connections are interconnected by the computerized apparatus to establish a call between the two experimenters and enable them to converse, the apparatus being cut into the call in order to acquire data about the call. The experimenters' opinions are solicited concerning their perceptions of the quality level they observe during their conversation. The apparatus evaluates consistency of the data collected with the nominal experimental conditions and the nominal quality level associated with the current test. Then, a determination is made as to how the current test is to be carried out as a function of a test plan and of the result of the evaluation.

Abstract: The voice quality of telephone calls is evaluated. A first connection is established between a computerized apparatus and a person acting as a first experimenter, and a second connection is established between the platform and a second experimenter. The first and second connections are interconnected by the computerized apparatus to establish a call between the two experimenters and enable them to converse, the apparatus being cut into the call in order to acquire data about the call. The experimenters' opinions are solicited concerning their perceptions of the quality level they observe during their conversation. The apparatus evaluates consistency of the data collected with the nominal experimental conditions and the nominal quality level associated with the current test. Then, a determination is made as to how the current test is to be carried out as a function of a test plan and of the result of the evaluation.

Abstract: For digitally demodulating a PSK analog signal transmitted as a linearly modulated carrier and representing successive symbols at a rate 1/T, the signal is sampled at a rate 1/.tau. at least twice the symbol rate 1/T, successive samples sampled with different filters selected from a plurality of filters corresponding to instants of no IES that are mutually offset by a fraction of the sampling .tau. that is optimum as regards coincidence between the respective sampling instant and an instant at which there is no ISI. A mean symbol demodulation rate equal to the symbol transmission rate is however retained. The signal as delivered by the selected filters in succession is decoded.