Abstract: Transmitting and receiving arrangements and methods in a Digital Subscriber Line (DSL) system having a plurality of modems and vectored transmission capability. A first part of an available frequency band is reserved for vectored DSL transmission and reception using modems operating in the first part of the frequency band. The remaining, second, part of the available frequency band is reserved for both vectored and non-vectored transmission using modems operating in the second part of the frequency band.

Abstract: Transmitting and receiving arrangements and methods in a Digital Subscriber Line (DSL) system having a plurality of modems and vectored transmission capability. A first part of an available frequency band is reserved exclusively for vectored DSL transmission and reception using modems operating in the first part of the frequency band. The remaining, second, part of the available frequency band is reserved for both vectored and non-vectored transmission using modems operating in the second part of the frequency band.

Abstract: Transmitting and receiving arrangements and methods in a Digital Subscriber Line (DSL) system having a plurality of modems and vectored transmission capability. A first part of an available frequency band is reserved for vectored DSL transmission and reception using modems operating in the first part of the frequency band. The remaining, second, part of the available frequency band is reserved for both vectored and non-vectored transmission using modems operating in the second part of the frequency band.

Abstract: The present invention relates to arrangements and methods in a Digital Subscriber Line (DSL) system. The basic idea of the present invention is to reserve a first part of an available frequency band exclusively for vectored DSL transmission and reception. The remaining part of the available frequency band can then be used either for only standard non-vectored transmission or for both for vectored DSL and for standard non-vectored DSL transmission. Therefore, the present invention makes it possible to get the full benefit of vectored transmission, on at least the first part of the frequency band, even if the DSL vector system cannot handle all DSL modems.

Abstract: The present invention relates to arrangements and methods in a Digital Subscriber Line (DSL) system. The basic idea of the present invention is to reserve a first part of an available frequency band exclusively for vectored DSL transmission and reception. The remaining part of the available frequency band can then be used either for only standard non-vectored transmission or for both for vectored DSL and for standard non-vectored DSL transmission. Therefore, the present invention makes it possible to get the full benefit of vectored transmission, on at least the first part of the frequency band, even if the DSL vector system cannot handle all DSL modems.

Abstract: Bit error rate estimates are used for measuring link quality in a radio telecommunications system. Unbiased, raw bit error estimates are produced from existing pilot symbols. The bit error rate estimates may be generated without incurring extra signaling overhead. More particularly, an estimation of link quality is obtained by receiving control signals in a radio receiver, where each control signal may include one or more pilot symbols deriving a channel estimate for each control signal, modifying each channel estimate as a function of the corresponding control signal's contribution to the channel estimate, and deriving a link quality measure based on said modified channel estimates.

Abstract: A method and apparatus for controlling transmission power levels in a CDMA cellular communication system are disclosed, whereby a third (middle) control loop is interposed between an inner loop and an outer loop to form a cascaded power control loop. Certain quality indicators are coupled to the outer loop and middle loop. The outer loop produces a quality target value for the middle loop. The middle loop produces the SIR target value.

Abstract: A transmission power control method and system are provided for use in a spread spectrum or CDMA mobile communications system, whereby an estimate of the achieved SIR is used as an additional parameter for the outer power control loop function. When the QoS and achieved SIR are both too low, the QoS is ignored and the SIR target value is instead controlled by the achieved SIR. Similarly, when both the QoS and achieved SIR are too high, the QoS is ignored and the SIR target value is instead controlled by the achieved SIR.

Abstract: Bit error rate estimates are used for measuring link quality in a radio telecommunications system. Unbiased, raw bit error estimates are produced from existing pilot symbols. The bit error rate estimates may be generated without incurring extra signaling overhead. More particularly, an estimation of link quality is obtained by receiving control signals in a radio receiver, where each control signal may include one or more pilot symbols deriving a channel estimate for each control signal, modifying each channel estimate as a function of the corresponding control signal's contribution to the channel estimate, and deriving a link quality measure based on said modified channel estimates.

Abstract: A method of a mobile radio system for synchronization a transmitter and receiver. The system relates to MC/DS-CDMA-system. In the system information is transmitted digitally in frames. For that purpose a data channel, a pilot channel and a synchronization channel are created. In the data channel the data blocks D0, D1, D2 etc are separated by a guard space .DELTA.. In the pilot channel, respective the synchronization channel, the information is arranged in blocks which are synchronous with each other. The repeating distance, A, of the pilot channel, corresponds to the length of one of the data blocks D0, D1, D2 etc. The repeating distance for the synchronization channel is S, corresponding to a number of blocks in the data channel. In the synchronization channel information is introduced into the blocks which indicates their relation to the data channel.

Abstract: A random access protocol system and method for communicating between a mobile station and a base station in a multi-access digital radio communication system, including the steps of cyclically repeating a random access sequence and transmitting each cyclically repeated random access sequence in an orthogonal frequency division multiplex format from the mobile station as an uplink transmission.

Abstract: A multi-user system includes radio channels which are independent and uncorrelated for different users. The system operates with frequencies which, due to multi-path propagation, are more or less attenuated for one user and more or less amplified for another user. Elements are arranged to detect or measure the attenuation/amplification for the different frequencies. The elements also prevent signal or information transmission at frequencies which drop below a predetermined lowest attenuation by disconnecting the frequency or frequencies in question and connecting a corresponding number of frequencies which pass the attenuation value criterion.

Abstract: The invention relates to a method and apparatus for synchronization of transmitters and receivers in digital transmission systems of the OFDM type. The system uses FFT technique to carry out the modulation and demodulation procedures. According to the invention, the transmitter sends synchronization frames with known frequencies and phase positions and with known time intervals in certain time slots. The receiver carries out a series of time-shifted FFT operations over the time position where the synchronization frame is calculated to be. For each operation, a cross-correlation is carried out in the frequency plane of the output signal with the known frequency function of the synchronization frame. The correlation maximum is detected, and this determines the time slot which contains the synchronization frame, whereupon this is used as time base for the following data frames.