Abstract: In a method, an apparatus and a system for data transmission, a plurality of transmitters are provided, which operate according to a communications standard for data transmission with a bandwidth that is higher than the transmission bandwidth. The transmitter is adapted to the transmission bandwidth, and the plurality of the adapted transmitters are allocated to different carrier frequencies in the transmission bandwidth for parallel data transmission.

Abstract: In a method, an apparatus and a system for data transmission, a plurality of transmitters are provided, which operate according to a communications standard for data transmission with a bandwidth that is higher than the transmission bandwidth. The transmitter is adapted to the transmission bandwidth, and the plurality of the adapted transmitters are allocated to different carrier frequencies in the transmission bandwidth for parallel data transmission.

Abstract: 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.

Abstract: The invention relates to a signal processing method which optimizes the bit error rate under pragmatic conditions. The signalling method is optimally matched to the radio channel, variable with time, in rapid sequence by means of linear operations. Uplink and downlink transmission sides are determined by an excess of antennae on the downlink transmission side. The estimations of the channel matrix in the one transmission direction, necessary for the matching of the transmitter, can, in the absence of common-channel distortions with the condition of channel reciprocity, be directly obtained from the estimations for the other transmission direction. By a suitable linear combination of the transmission signals and, optionally, also the received signals, an error-free bi-directional transmission of data streams can be achieved in Rayleigh and Rice channels with significantly lower transmission powers than in purely receiver-side linear signal processing.

Abstract: 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.

Abstract: The invention relates to a signal processing method which optimizes the bit error rate under pragmatic conditions. The signalling method is optimally matched to the radio channel, variable with time, in rapid sequence by means of linear operations. Uplink and downplink transmission sides are determined by an excess of antennae on the downplink transmission side. The estimations of the channel matrix in the one transmission direction, necessary for the matching of the transmitter, can, in the absence of common-channel distortions with the condition of channel reciprocity, be directly obtained from the estimations for the other transmission direction. By means of a suitable linear combination of the transmission signals and, optionally, also the received signals, an error-free bi-directional transmission of data streams can be achieved in Rayleigh and Rice channels with significantly lower transmission powers than in purely receiver-side linear signal processing.

Abstract: An optical frequency generator provided with an optical comb generator for generating a plurality of frequencies including a central frequency and side bands spaced by a frequency transmitter. The central frequency is adjustably combined with the spectral component of a reference light source. Modification of frequency differences between the central frequency and the reference light source and modification of the transmission frequency of the frequency transmitter displaces the frequency comb of the comb generator or alters its spectral width. A heterodyne receiver connected to the output of the comb generator and a test light source of unknown frequency is provided for determining the frequency of the latter.