Patent application number | Description | Published |
20100316107 | FREQUENCY DOMAIN EQUALIZATION METHOD FOR CONTINUOUS PHASE MODULATED SIGNALS - A method for frequency domain equalization of a cyclic CPM signal received via a channel is disclosed. In one aspect, the method includes representing the received cyclic CPM signal as a matrix model comprising a channel matrix representing influence of the channel, separate from a Laurent pulse matrix and a pseudocoefficient matrix respectively representing Laurent pulses and pseudocoefficients determined by Laurent decomposition of the received cyclic CPM signal. The method may further include applying a channel equalizer on the separate channel matrix and after the equalization. It may further include demodulating the received cyclic CPM signal by the matrix model, the demodulation exploiting known correlation properties of the Laurent pulses and the pseudocoefficients. | 12-16-2010 |
20100316166 | METHOD FOR GENERATING A DATA BLOCK FOR TRANSMISSION USING A CPM SCHEME - A method for generating a data block for transmission using a continuous phase modulation scheme is disclosed. In one aspect, the method includes inserting payload data in the data block, the payload data having a plurality of payload symbols, each involving an state change in a continuous phase modulation waveform generated from the data block in one of two opposite directions. It may include inserting state compensation data in the data block for cancelling out the state changes, such that the waveform has an end state at the end of the data block equal to a begin state at the beginning of the data block. The state compensation data is determined by determining from the state changes an overall state change caused by the payload data over the waveform and by selecting a set of compensation symbols for the state compensation data on the basis of the overall state change. | 12-16-2010 |
20120236926 | FREQUENCY-DOMAIN ADAPTIVE FEEDBACK EQUALIZER - A circuit for adaptive feedback equalization is disclosed. In one aspect, the circuit includes a frequency-domain feedforward filtering section and a feedback filtering section, a slicer to slice a block of equalized symbols, a summing module for summing outputs of the filtering sections thereby yielding the block of equalized symbols. First and second updating modules provide coefficient updates to the filtering sections. The updating modules are fed with a frequency-domain converted block of error signals indicating the difference between the block of equalized symbols at the slicer input and the block of sliced symbols at the slicer output and for computing updates using the frequency-domain converted block of error signals. A time-domain compensation module receives a time-domain version of the updated filter coefficients of the feedback filtering section and symbols of the block of sliced symbols. It adds a feedback error compensation signal to the block of equalized symbols. | 09-20-2012 |
Patent application number | Description | Published |
20110291891 | METHOD AND SYSTEM FOR MIXED ANALOG/DIGITAL BEAMFORMING IN WIRELESS COMMUNICATION SYSTEMS - A method is disclosed for mixed analog/digital beamforming in a wireless communication system having transmit and receive antennas and analog front-ends connected to either the transmit antennas or the receive antennas. The method includes determining transmit and receive analog/digital beamforming coefficients by a) determining information representative of communication channels formed between a transmit antenna and a receive antenna, b) defining coefficients representing the transmit analog beamforming coefficients and the receive analog beamforming coefficients, c) determining a beamforming cost function using the information and the coefficients, the cost function taking into account the analog front-ends, d) computing an optimized set of transmit/receive analog beamforming coefficients by exploiting the cost function, e) deriving an estimate of the frequency responses of the communication channels using the information determined in process a, and f) deriving for each channel transmit/receive digital beamforming coefficients using the estimated frequency responses and the optimized beamforming coefficients. | 12-01-2011 |
20110317575 | METHOD AND APPARATUS FOR MULTI-USER MULTI-INPUT MULTI-OUTPUT TRANSMISSION - Embodiments of the present invention relate to methods and systems of transmitting data signals from at least one transmitting terminal with a spatial diversity capability to at least two receiving user terminals, each provided with spatial diversity receiving device. The methods and systems are useful, for example, in communication between terminals, e.g., wireless communication. In certain embodiments, transmission can be between a base station and two or more user terminals, wherein the base station and user terminals are each equipped with more than one antenna. | 12-29-2011 |