Abstract: A data base query submitted in natural speech normally requires a dialog with the data base system, which repeatedly prompts the user to submit further statements. From each speech utterance submitted by the user a plurality of sets of statements are derived. The statements in these sets are tested for consistency with stored statements determined previously and consistent new statements are stored and stored statements are corrected or verified. Moreover, the stored statements are basically used in each dialogue step in order to derive from these statements an optimum request for the user by the system. Preferably, the statements are also stored with probability values or reliability values, the corresponding values of new statements to be stored being derived from the reliabilities of the statements of the respective speech utterance and the corresponding consistent statements stored.

Abstract: In speech recognition, a reliability measure can be determined by using various sentence hypotheses with a decreasing acoustic similarity. However, if a databank inquiry is to be derived from such a speech signal, often only individual words or even a single word from the utterance are required as data for such a databank access. Such a data, for example, the time, may be contained in the speech utterance in various ways. In accordance with the invention, a reliability measure for such a data rather than for a given word is determined, in which the same data may be constituted by various words. Thus, these various words are treated equally for determining the reliability measure.

Abstract: A radio transmission system having a base station and a mobile station is disclosed. A controller dynamically changes in real-time the allocation of channels in response to changes in signal propagation and traffic conditions between the base and mobile stations. The allocation of channels is based on use of a Kohonen model and is determined by a space-dependent component and/or a time-dependent component. The space-dependent component is determined by signal strengths received by the base and mobile stations and the time-dependent component are determined by activity of the channels.

Abstract: A spread-spectrum based cellular mobile radio system resolves average mutual interferences (I.sup.u (j).sub.av, I.sup.d (j).sub.av) between radio zones j, j') from a total interference experienced in a radio zone (j), using statistical methods. First, interference measurements are carried out in the radio zones (Z1, Z2), and data is transmitted to a central control arrangement (CA) which resolves the average mutual interferences. Then, these average mutual interference (I.sup.u (j).sub.av, I.sup.d (j).sub.av) are used in an optimization process for acquiring access control parameters (x) for controlling traffic per radio zone (Z1, Z2). In the optimizing process various objective functions may be applied so as to fulfil system operator demands. Thus, system overload is avoided, and further, a flexible tool is provided for satisfying operator demands.

Abstract: A cellular mobile radio systems includes fixed stations and mobile stations, a radio cell being subdivided into sub-cells and each sub-cell being assigned its own allocation of radio channels. The values of radio parameters of the fixed stations are measured and evaluated for assigning a mobile station to a sub-cell. To achieve an additional increase of the radio channel capacity of such system, a position vector is assigned to each respective mobile station which is derived from the measured parameters. A mobile station is then assigned to a specific sub-cell on the basis of its position vector.

Abstract: In a cellular mobile radio network a limited number of available channels must be allocated among the various cells, and the efficiency of such allocation is highly variable with changing traffic conditions in the network. To solve this problem the invention determines all possible radio situations which may arise in the network, including the radio positions of a mobile station and occupancy of the various channels. The individual components of each possible radio situation are then compared with predetermined thresholds so as to reduce the multiplicity of such situations to a relatively small number of classified radio situations each of which has its own channel list allocated thereto. When a channel is requested for a mobile station, the relevant classified radio situation is determined and channel assignment is made from the channel list applicable to that classified situation.

Abstract: A mobile radio system includes fixed stations and mobile stations, a free channel for establishing connection to a mobile station being selected from a predetermined channel list for each fixed station. The individual station lists are initially assigned in a radio network planning phase. To adjust to changes in the system which only occur after it is in operation, the assignment of radio channels is modified on the basis of measured data obtained during actual operation of the system. In this way the system becomes self-adaptative.