Abstract: The present invention relates to a method for the transmission of data in a multi-carrier system, provided with a frequency band, the carrier frequencies of which are distributed in a sub-carrier band, dividing the frequency band. On the transmission side, dependent on current transmission properties, an adaptive pre-emphasis of the transmission signal is carried out for a part of the carrier frequencies in the sub-carrier band. The transmitter thus has the capacity to determine current transmission properties as well as adaptive pre-emphasis of a part of the carrier frequencies in the sub-carrier band of the transmission signal.

Abstract: The present invention seeks to improve data exchange in a communications system that is especially standardized according to IEEE 802.11a. For this purpose, when the transmission medium, preferably an IEEE 802.11 system with a distributed coordination function (DCF) is accessed in a decentralized manner, pilot signals are transmitted from the transmitter to the recipients using a number of transmission modes and then an allocation table regarding the transmission modes is calculated by the recipient on the basis of the pilot symbols received. The recipient transmits the allocation table to the transmitter so that the subsequent data exchange can proceed on the basis of the allocation table. In the case of centralized access, preferably an IEEE 802.11 system with a point coordination function (PCF), data exchange is improved in that the subsequent data are adaptively modulated already when the allocation table is transmitted.

Abstract: The invention relates to a transmitter-receiver pair for improved data transmission in a multi-carrier system and to a corresponding method, according to which a chain coding is used. To this end, a transmitter has a first coding stage, a transmission-demultiplexer stage, a second coding stage, a modulator stage, a transmission multiplexer stage and a multi-carrier modulator, whereby said transmission-demultiplexer stage and the transmission multiplexer stage are controlled by a bit loading device. Similarly, the receiver has a multi-carrier demodulator, a receiver demultiplexer stage, a first decoding stage, a receiver multiplexer stage and a second decoding stage, whereby the receiver multiplexer stage and demultiplexer stage are in turn controlled by the bit loading device.

Abstract: A method for data communication between a single-carrier system is provided, wherein a received single-carrier signal is spectrally scanned by the multi-carrier system which decides upon received data according thereto and/or simulates a single-carrier signal with its own carriers.

Abstract: The invention relates to a method for reducing signaling overhead in a multicarrier system with dynamic bit allocation per subcarrier and to a corresponding transmitter/receiver device, wherein an established bit allocation table (BAT) that is provided with an index (I) is stored in a BAT storage device (LUT). In order to reduce signaling overhead, only the corresponding index (I)of an existing bit allocation table is transmitted (S6).

Abstract: A method for the radio coverage of a mobile terminal of a mobile radio network in the catchment area of an intermediate station which is used as a converter, wherein: in the case of an existing connection between the mobile radio network and the mobile terminal, a connection is first set up on an internal frequency and the connection is then handled via the intermediate station; in the case of an existent connection from a mobile terminal via an intermediate station to the mobile radio network, the intermediate station will hand over the connection to the mobile terminal again directly to the mobile radio network when the mobile terminal is removed from the internal area of reception; and in the case of a new setting-up of a connection from the mobile terminal to the mobile radio network, for setting up the connection, the mobile terminal first, or after an unsuccessful connection set-up attempt with a mobile radio frequency, attempts to establish connection to an intermediate station on an internal frequency

Abstract: The invention relates to a method for the parallel transmission of identical data from a transmitter/receiver device to a plurality of terminals, said transmission at least partially proceeding via a radio connection. Common transmission capacities for a transmission of quality information regarding the transmission quality of the data are provided to the transmitter/receiver device in this radio connection for the purpose of transmission by a plurality of terminals.

Abstract: The invention relates to a method for accessing stations (WT, AP, APTi) onto a common transfer medium, wherein said stations (WT, AP, APTi) share the common transfer medium with other stations. In order to apportion the available transfer capacity as efficiently as possible, said stations inform each other of their capacity needs by sending messages when necessary. The sent messages can contain information on priority and capacity requirement. Stations which receive the sent capacity requests release unrequired transfer capacity or transfer capacity which is not urgently required, so that said capacity can by used by a station in need. The corresponding information can also be transferred by other stations, e.g. by several hops.

Abstract: The invention relates to a method and device for improving, on the receive side, the transmission quality (residual/bit error rate) of a data transmission system, which is based on orthogonal frequency division multiplexing (OFDM) technology and which is negatively influenced by narrow-band harmonic interference signals. The invention takes into account two technical measures. In one technical measure, a received OFDM symbol is processed by means of a cyclic rotation of the OFDM receive symbol and of a subsequent Nyquist windowing in the time domain whereby leading to a reduction of the interference spectrum outside of the sub-carrier bandwidth. In the other technical measure, a channel estimation of the channel transmission function on the sub-carrier level is effected in parallel with the first technical measure, and the signal-to-noise ratio is calculated or estimated by estimating the interference power on the sub-carrier level.

Abstract: In a radio communications network, the time is divided into a succession of frames for conducting data communications with subscriber stations located within a coverage area of two central stations of the network. In a first broadcast phase of each frame, a first central station (AP1) transmits first frame format information (BCH), which defines a first downlink phase of the frame (DL phase) and a first uplink phase (UL phase). In the same frame, a second central station transmits, on the same frequency, second frame format information (BCH), which defines a second downlink phase and a second uplink phase for the communication of subscriber stations (MS) with the second central station (AP2), whereby the phases within a frame do not overlap.

Abstract: A method for disturbance-free operation of at least two base stations working according to the CDMA (Code Division Multiple Access) principle in a universal mobile telecommunications system, preferably in-house base stations, with partially overlapping radio fields relative to one another and/or with respect to a telecommunications radio cell network, wherein, the base stations transmit the communications information using the CDMA multiple access method, at least two participating stations carry out an autosynchronization procedure for the purpose of eliminating disturbing interferences on account of the overlapping radio fields and identical transmission frequency, chip synchronism being produced as a result and, consequently, good reception of the orthogonal codes, i.e. good subscriber separation of the multiple access method, is ensured.

Abstract: In order to control the transmitting power provided for point-to-multipoint telecommunications links in a telecommunications system with wireless telecommunication and uncoordinated unlicensed system operation, without significant restriction of the transmitting range, use is made of the fact that the maximum number of mobile stations (MS1 . . . MSn) registered in a base station (BS1) is known. Thus, the base station knows at any time how many and which mobile stations are registered. If all mobile stations are registered (NACT=NSCHED), the base station can match the transmitting power to the mobile station received as the “weakest one”. In other cases, if not all mobile stations are registered (NACT≠NSCHED), the base station will alternately transmit with the maximum transmitting.