Abstract: The present invention relates to a method for selecting satellites (SV1-SV32) to be used for positioning in a positioning system. The positioning system comprises information on the orbits of the satellites (SV1-SV32). In the method, at least one satellite (SV1-SV32) to be searched for is selected at a time, and a searching step is performed to find out if the signal transmitted by at least one selected satellite (SV1-SV32) can be received. In the method, at least a first searching step and at least one continued selection step are performed, wherein in the continued selection step, at least one satellite (SV1-SV32) is selected at least partly on the basis of the findings of the previous searching step. The selection step is followed by the satellite searching step.

Abstract: A method and apparatus for coding successive pitch periods of a speech signal. Based on a priori knowledge of statistical properties of successive speech periods, a shaped lattice structure is designed to cover the most probable points in the pitch space. The codebook index search starts with finding an open-loop estimate in the pitch space considering all dimensions and refining the open-loop estimate in a closed-loop search separately in each dimension based on the shaped lattice structure. The closed-loop search for the first subframe is for obtaining an absolute pitch period or a delta pitch while the closed-loop search for each of the other subframes is for obtaining a delta pitch for the respective subframe.

Abstract: A method and apparatus for coding successive pitch periods of a speech signal. Based on a priori knowledge of statistical properties of successive speech periods, a shaped lattice structure is designed to cover the most probable points in the pitch space. The codebook index search starts with finding an open-loop estimate in the pitch space considering all dimensions and refining the open-loop estimate in a closed-loop search separately in each dimension based on the shaped lattice structure. The closed-loop search for the first subframe is for obtaining an absolute pitch period or a delta pitch while the closed-loop search for each of the other subframes is for obtaining a delta pitch for the respective subframe.

Abstract: The invention relates to a method for controlling the operation of a receiver. In the method, at least one spread spectrum modulated signal is received on at least two receiving channels, and a reference signal is formed on said at least two receiving channels by using a reference code corresponding to the code used in the modulation of the signal to be received. Further, in the method, the received signal is correlated with the reference signal. In the receiver, a set of correlators is used, and for at least one correlator of said set of correlators, a receiving channel is selected, wherein said at least one correlator is used in the correlation of the signal received on the receiving channel with the corresponding reference signal.

Abstract: The invention relates to a method for determining a boundary of an information element, in which repetition-coded signal transmitted by satellites is received, which signal is modulated with information elements. A group of symbols forms one information element. In the method a group of reference values are formed on the basis of the received signal. Of these reference values at least one vector is formed wherein the number of the elements corresponds to the number of symbols used in the transmission of the information element. A determination vector is formed on the basis of said at least one vector, whereafter the greatest of the elements of said determination vector is searched, wherein the index of said element indicates the boundary of the information element.

Abstract: This invention presents a voicing determination algorithm for classification of a speech signal segment as voiced or unvoiced. The algorithm is based on a normalized autocorrelation where the length of the window is proportional to the pitch period. The speech segment to be classified is further divided into a number of sub-segments, and the normalized autocorrelation is calculated for each sub-segment. If a certain number of the normalized autocorrelation values is above a predetermined threshold, the speech segment is classified as voiced. To improve the performance of the voicing determination algorithm in unvoiced to voiced transients, the normalized autocorrelations of the last sub-segments are emphasized. The performance of the voicing decision algorithm can be enhanced by utilizing also the possible lookahead information.

Abstract: The present invention relates to a method for selecting satellites (SV1-SV32) to be used for positioning in a positioning system. The positioning system comprises information on the orbits of the satellites (SV1-SV32). In the method, at least one satellite (SV1-SV32) to be searched for is selected at a time, and a searching step is performed to find out if the signal transmitted by at least one selected satellite (SV1-SV32) can be received. In the method, at least a first searching step and at least one continued selection step are performed, wherein in the continued selection step, at least one satellite (SV1-SV32) is selected at least partly on the basis of the findings of the previous searching step. The selection step is followed by the satellite searching step.