Siemens Aktiengesellschaft

Other

Durham Logistics, LLC

Christopher Brunner

Martin Haardt

Alexander Seeger

Bernhard Raaf

Joachim Hammerschmidt

A method and system for reducing interference in a cellular radio communications network. At least one parameter affecting user terminals within a cell is adjusted such that the cell boundary is modified, such that interference in the network is reduced. In alternative embodiments the at least one parameter is adjusted adaptively.

Method and system for adaptive modification of cell boundary

A radio communications system has subscriber stations and a base station that is provided with an antenna system with a plurality of antenna elements that emit a downlink signal in a weighted manner with coefficients of a weighting vector. In order to form a beam, a plurality of weighting vectors is determined at the subscriber station and the determined weighting vectors are transmitted to the base station. In a subsequent working phase, the subscriber station selects a dominant vector among the determined weighting vectors and transmits an indicator of the selected weighting vector to the base station.

Beam forming method

In a radio communication system, a beam is formed between subscriber stations and a base station which has an antenna device with several antenna elements. The antenna elements emit a downlink signal based on respective weighing with coefficients of a weighting vector. A plurality of weighting vectors are determined at the subscriber station in an initialization phase and transmitted to the base station. In a subsequent working phase, the subscriber station selects a dominant weighting vector from the weighting vectors and transmits a designation of the selected weighting vector to the base station.

A method controls the downlink beam in a radio communication system. The radio communication system has an antenna system with several antenna elements. The method involves a) examining a received uplink signal sent by a transmitter for the existence of phase correlations between parts of the uplink signal received from various antenna elements of the antenna system, and b) if a phase correlation is detected, assigning at least one source direction to the uplink signal and sending the downlink signal in the source direction. If a phase correlation is not detected, however, the downlink signal is sent in a non-directional manner in the form of several components produced using at least one diversity technique.

Method for controlling the formation of a downlink beam

A receiver that operates to recover data from spread spectrum radio signals, which include radio signals generated from a combination of the data and a data spreading code associated with the user and radio signals generated from a combination of a predetermined sequence of pilot data and a pilot spreading code. The receiver includes a plurality of antennas, each arranged to detect a different version of the radio signals. Base band conversion means is coupled to the plurality of antennas and arranged to generate, for each antenna, base band signal samples representative of the version of the radio signals. Data recovery means operates to correlate each version of the signal samples with respect to the pilot spreading code, form at least one covariance matrix from a frequency domain representation of a predetermined temporal window of the correlated pilot signals samples, correlate each version of the signal samples with respect to the user data spreading code, form a frequency domain representation of each version of the data correlated signal samples, and detect the data from the frequency domain data correlated signal samples in combination with the at least one covariance matrix. A method used with the receiver is also provided.

Receiver and method of recovering data from radio signals

A method for measuring characteristics of radio channels, in which the signals are received by a total of M receiving sensors in a linear antenna array, in which case the respective received signals are composed of wave elements of a transmitted signal with a different incidence direction and different delay, the transmitted signal contains a preselected test sequence, and the incidence angle as well as the delay of the dominant wave fronts are estimated simultaneously, taking account of the chip signal form of the test sequence, the signals from each antenna sensor are demodulated, and sampling is then carried out with M samples per chip in the test sequence. In this case, the resultant N &times;M samples are transformed to the frequency domain by discrete Fourier transformation, and the values which are obtained from this are corrected taking account the spectrum of the chip signal form, in which case the line vectors formed from the values obtained for each sensor can be combined to form a data matrix X (n), which contains invariances which characterize the channel.

Method and measurement configuration for measuring the characteristics of radio channels

The characteristics of radio channels are measured. The signals received by a plurality M,of receiving sensors of a two-dimensional antenna array are composed of wave elements of a transmission signal with regard to the azimuth and the elevation of a different two-dimensional incidence direction and different delay. The transmission signal contains a preselected test sequence, and the incidence angle as well as the delay of the dominant wave fronts are estimated simultaneously taking account of the chip signal form of the test sequence. The signals of each antenna sensor are demodulated, and sampling is then carried out with M,samples per chip in the test sequence. The resultant samples are transformed to the frequency domain by discrete Fourier transformation, and the resultant values are corrected taking account of the spectrum of the chip signal form, wherein the line vectors formed from the values obtained for each sensor can be combined to form a data matrix X,, which contains invariances that characterize the channel in the space/frequency domain.

A radio communications receiver for detecting first and second contemporaneously transmitted radio signals representative of first and second data. An adaptive antenna detects at least one wave front from the first radio signals, and at least one wave front from the second radio signals. A first radio detector which regenerates first data from the first wave front. An interference canceller subtracts the first radio signals, reconstituted from the first data, from the second wave front, dependent on interference from the first wave front to the second wave front. A second data detector regenerates the second data from the second wave front after the subtraction of the first wave front consequent upon the second radio signals. The first and second data are communicated contemporaneously on at least common parts of the radio frequency spectrum. The present invention finds application with wide band code division multiple access signals (W-CDMA) signals as well as time division-code division multiple access signals (TD-CDMA), and time division multiple access signals (TDMA) such as those generated by the GSM system.

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San Francisco, CA, United States of America

Christopher Brunner