Siemens Aktiengesellschaft

Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V.

Nokia Siemens Networks Gmbh & Co Kg

Heinrich Hertz Institut Fuer Nachrichtentechnik Berlin Gmbh.

Clemens Von Helmolt

Volker Jungnickel

Thomas Haustein

Wolfgang Zirwas

Udo Krueger

Slawomir Stanczak

Josef Martin Eichinger

Andreas Forck

Eduard Jorswieck

Klaus-Dieter Langer

Volker Pohl

Jelena Grubor

A method detects a first baseband signal sent by a first sending station via an air interface to a first radio station of a radio communications system. A first receive signal, which contains the first baseband signal superposed with at least a second baseband signal sent by a second sending station to a second radio station, is received by the first radio station. The first radio station uses at least a second receive signal received by the second radio station for detection of the first baseband signal. The second receive signal contains at least the second baseband signal, and is used to at least partially cancel the interference in the first receive signal caused by the second baseband signal.

Method, system and radio station for interference cancellation

An adaptive signal processing method to achieve an increase in capacity of data transfer systems, in which control data is returned via a backward channel. The method provides signal processing using an electrical sub-carrier sub-division according to frequency, the electrical sub-carrier with the lowest carrier frequency being permanently used as the backward channel (RC) for transferring control information relating to the current transfer quality of each sub-carrier. An electrical modulation on N parallel sub-carriers takes place in the transmitter (Tx) and then an optical intensity modulation is carried out for a serial data transfer in the optical channel (IRWC). The discrete division of the information to be transferred to the sub-carriers in a real-time operation can take place by the implementation of specific bit-loading algorithms.

Dynamic data-rate adaptive signal processing method in a wireless infra-red data transfer system

In a radio communication system, at least a first frequency band is subdivided into C radio resource units which are allocable for radio transmissions between radio stations and terminals. Each radio resource unit has at least two adjacent subcarriers, for allocation of at least a first resource unit for a data transmission between a terminal and a radio station. The radio station receives from the terminal a first short training symbol which has spectrally the same bandwidth as the first frequency band and includes at least Q frequency carriers, where Q is greater or equal to C, but smaller than the total number of subcarriers. The radio station estimates the radio channel for at least the first radio resource unit using the first short training symbol, and an allocation of the first radio resource unit to the terminal is broadcasted by the radio station.

Method for operating radio communication system, including sending station and receiving station thereof

A radio transmission method and a wireless transmission system comprising multiple transmitter and receiver antennae simultaneously operating within the same frequency range and space-time encoders and decoders. Data transmission and channel matrix measurement can take place synchronously. Characteristic pilot signals that are unequivocally recognizable are superimposed with low noise on the data subsignals in the transmitter and are used in the receiver for the analog measurement of the channel matrix in a weighting unit and for the analog recovery of the transmitted data subsignals from the received signals. The measured analog values are digitally processed in a signal processor. The weightings thus determined are then summed in an analog signal processing unit.

Indoor radio transmission method for parallel radio transmission of digital data substreams and a mobile radio transmission system

A bidirectional signal processing method uses parallel transmission of digital transmitted data streams in a multiple input-multiple output system. Related art methods generate high bit error rates mostly in singular transmission channels. For this reason, the rank-adaptive signal processing method provides that the number nof active subchannels are varied according to the actual channel behavior in order to effect a robust data transmission even in singular radio channels based on a transmit-side and receive-side channel knowledge and a modification of the data vector by a linear matrix vector multiplication while introducing a factor gamma for limiting the maximum transmit power. The maximum transmit power is then only distributed to the currently activated subchannels so that no transmit power remains unused. Another optimization of the number of subchannels noccurs when selecting the modulation and encoding methods. During the optimal rank-adaptation according to the water-filling principle, another power is allocated to each subchannel. Another modulation and encoding method is accordingly selected for each data stream. During the suboptimal rank-adaptation according to the channel inversion principle, all subchannels have the same power whereby enabling the data streams to be modulated and encoded in a common source.

MIMO signal processing method involving a rank-adaptive matching of the transmission rate

Optical frequency generator

An optical network, particularly fashioned as a homodyne or heterodyne receiver wherein a local oscillator (2) of an optical homodyne or heterodyne receiver comprising an optical wave guide network (1) is isolated from generally anisotropic reflections from the network (1) in order to preserve the stability and tunability of the oscillator (2) and a polarization filter (10), a polarization converter (11) and a phase shifter (12) are successively arranged in the direction of the outgoing optical wave in the beam path of the wave emitted by the oscillator (2) and reflected by the network (1) for optical homodyne or heterodyne reception.

Growing community of inventors

Berlin, Germany

Clemens Von Helmolt