Abstract: A method in a mobile radio station to select one of a number of dedicated control channels (DCCH1-21) which are transmitted from a number of base stations (B1-B21) in a mobile radio system. In the mobile station there is an equalizer to compensate for the multipath propagation characteristics of the radio medium between the mobile station and a certain base station. This equalizer is power consuming and should not be used if not necessary. According to the method an investigation is carried out in the mobile station whether or not the equalizer can be disconnected during the initialization of a call from the mobile to a base station. The signal quality of the dedicated channel (DCCH1) which has the greatest signal strength is measured without the equalizer. If the signal quality is not acceptable, a new detection is made with the use of the equalizer.

Abstract: A method in a mobile radiotelephone system in which an address is added to a symbol message in a control channel in order to exclude interfering connections operating on the same radio frequency as the actual connection between a base station and a mobile station. According to the proposed method, the address (A1) to the intended receiver is added to the message (M) and an error check word (E) is calculated based on both the address (A1) and the message (M). Before transmitting to the receiver, the added address is removed and the transmitted control signal includes only the symbol message (M) and the error check code (E). In the receiver, the specific address for the receiver is added to the received control signal and the same calculation is carried out as in the transmitter in order to get an accept/reject signal.

Abstract: The invention relates to a method and an arrangement for controlling the frequency of a radio-receiver which receives signal-sequences which have been subjected to interference and which include a synchronizing-sequence and a data-sequence. A signal-sequence is converted into signal-points intended for analysis. A Viterbi-analyzer is adapted to the prevailing interferences with the aid of the synchronizing-sequence. The data-sequence is Viterbi-analyzed through a large number of calculating stages to determine the bit-sequence of the data-sequence. A bit-sequence is extracted during the Viterbi-analysis, with a time-delay, subsequent to effecting a few calculating stages, and a corresponding extracted signal-point is calculated. The analysis-intended signal-point corresponding to the extracted signal-point is divided, time-delayed, and phase-compared with the extracted signal-point.

Abstract: The invention relates to a cellular digital mobile radio system including base stations (B.sub.m, B.sub.n) and mobile stations (MS.sub.1, MS.sub.2) with transmitters and receivers. The invention also relates to a method of transmitting message information digitally between mobile and base stations in such a system. In accordance with the invention, at least two base station transmitters (B.sub.ma, B.sub.mb, B.sub.na, B.sub.nb) at a given transmitting distance from each other are assigned to each of certain cells (C.sub.m, C.sub.n) within a restricted geographical area. The base station transmitters which are assigned to the same cell transmit digitally modulated radio signals within the same frequency range at least partially simultaneously to the mobile stations of the cell. The radio signals from different base station transmitters associated with the same cell are digitally modulated with the same message information to the mobile stations in the cell.

Abstract: A method of reducing blockages and call interruption in handling over calls in a cellular mobile radio system. When the signal strength from a base station to a mobile and vice versa falls below a given value the handover shall take place to another base station. In order that the call will not be interrupted, a smaller number of channels are reserved, so-called rescue channels, from the ordinary channels in the system. The rescue channels can be fixed or dynamic for a given base station.

Abstract: The invention relates to a combination of a switched telecommunication network, a telepoint connected to the network and a portable radio terminal constituting part of a residential equipment or an extension to a PABX, the portable radio terminal when served by a telepoint radio transceiver instead of its residential or exchange radio transceiver uses the telepoint and the network for calling its residential base radio station or PABX and reporting serving telepoint to a location store, calls to the portable radio terminal thereafter being transferred by the residential equipment or PABX through the network to the telepoint in accordance with information in the location store, whereby the portable radio terminal or cordless telephone may be called through the network and telepoint when in proximity of a telepoint.

Abstract: Apparatus for correcting the frequency in a coherent receiver associated with a radio communication installation, e.g. a mobile telephone installation for transmitting digital information in time-division multiplex. The receiver includes a controllable local oscillator (7) for generating a mixing signal for converting the frequency of a received signal, and unit (4,8,9) for calculating a frequency error and generating a control signal (f") to the oscillator (7). Each new value of the control signal (f") is dependent on a previous value and on the calculated frequency error, and is utilized for correcting the frequency of said mixing signal. At least the major part of a frequency error in the receiver is thus eliminated. A possibly remaining part of a required frequency correction is carried out by a frequency change in the baseband. This is achieved with the aid of a unit (11) included in the receiver, and adapted to perform regularly repeated phase shifts of a signal (I,Q) in the baseband by a value (V.sub.