Abstract:
A method includes receiving at least two space-time coded signals from an antenna system associated with a first station, determining complex channel state information based on the received space-time coded signals, and sending the complex channel state information to the first station. In an alternative embodiment, a method includes transmitting at least two space-time coded signals in respective beams of a multi-beam antenna array, measuring a channel impulse response for each space-time coded signal at a second station, and sending an indicia of a selected set of least attenuated signals from the second station to the first station. The multi-beam antenna array is associated with a first station. The beams transmit a signature code embedded in each respective space-time coded signal, and the signature codes are orthogonal so that the second station can separate and measure the channel impulse response corresponding to each space-time coded signal.
Abstract:
The present invention relates to acoustic properties of a terminal device of a telecommunication network. To improve the capability of the terminal device to maintain the sound quality good while the distance between the speaker and the ear changes, the enclosure of the terminal device is provided with means (71, 81) for conveying the acoustic waves generated backwards by the speaker (30) of the device inside the enclosure to a cavity-like antenna space (80) intended for the antenna of the terminal device.
Abstract:
The invention relates to a method of transmitting data in a radio channel from a transmitter to a receiver, and to a transmitter and a receiver implementing the method. The method includes setting a radio channel quality requirement according to the user and system information; setting a data transfer delay requirement; determining a radio channel coherence time; channel encoding the data; selecting interleaving depth using the radio channel coherence time and the data transfer delay as decisive parameters; interleaving the channel coded data; if the radio channel quality requirement is not fulfilled, selecting at least one transmit diversity antenna besides the main antenna so that the radio channel quality requirement will be fulfilled; transmitting modulated, interleaved and channel coded data with the selected antennas.
Abstract:
A radio system includes a base station and a remote station. The base station includes a space-time encoder, an antenna system, a transmitter, a base station receiver, and a power management controller. The space-time encoder encodes a stream of symbols into first and second space-time coded signals, and the transmitter transmits the first and second space-time coded signals at respective first and second initial transmit powers from the antenna system so as to form respective first and second radiation patterns. The base station receiver receives power coefficient indicator information from the remote station, and the power management controller determines first and second adjusted transmit powers based on the respective first and second initial transmit powers and the power coefficient indicator information. In an alternative embodiment, a transmit station of a radio system includes a circuit to determine an angular power spectrum, a space-time encoder, and a transmitter. The space-time encoder encodes first and second symbols into first and second space-time coded signals, and the transmitter transmits the first and second space-time coded signals in respective first and second beams so that the first and second beams are contained within an angular spread of the angular power spectrum.
Abstract:
The invention relates to a RAKE receiver of a CDMA system using IRC, the receiver receiving a radio signal by using at least two antenna branches. In accordance with the invention a RAKE finger comprises: a weighting coefficient part for forming weighting coefficients maximizing the Signal-to-Interference-and-Noise Ratio for each antenna branch; a multiplier for multiplying a pilot part, despread by a despreader in each antenna branch, by a weighting coefficient; a multiplier for multiplying a data part, despread by a despreader in each antenna branch, by a weighting coefficient; an antenna branch summer for combining the despread pilot parts, received via the separate antenna branches and multiplied by the weighting coefficient, to one pilot signal; an antenna branch summer for combining the despread data parts, received via the separate antenna branches and multiplied by the weighting coefficient, to one data signal. In addition, the receiver comprises a RAKE finger summer for combining the data signals of the RAKE fingers operating by different delays to a sum data signal representing the received bits.
Abstract:
The invention relates to a method, a base station and a computer program for selecting a spatial transmission method for a next downlink transmission in a base station. The base station can be a WiMAX, a UMTS or a 3 GPP LTE base station. According to the invention the base station makes a selection between beamforming (BF), space-time coding (STC) or MIMO for a next downlink frame. The selection is based on uplink measurements and feedback information from a particular mobile station whereto the next downlink frame is to be transmitted.
Abstract:
An apparatus of a multi-antenna telecommunication system includes a beam forming unit configured to form at least two antenna beams, and a signal feeding unit connected to the beam forming unit and configured to feed beam-specific data streams to the beam forming unit. The beam-specific data streams are allocated to one and the same transceiver of the wireless telecommunication system, and each data stream includes independently and separately encoded data signals.
Abstract:
A radio channel simulation system comprises a plurality of input buses for receiving a beam-specific transmit signal. A transformation module transforms a channel model from antenna domain to beam domain by using a transformation algorithm and beam forming weights. The channel model represented in the beam domain is inputted into a processing module which processes the beam-specific transmit signals according to the channel model represented in the beam domain.
Abstract:
The invention relates to a method, a base station and a computer program for selecting a spatial transmission method for a next downlink transmission in a base station. The base station can be a WiMAX, a UMTS or a 3GPP LTE base station. According to the invention the base station makes a selection between beamforming (BF), space-time coding (STC) or MIMO for a next downlink frame. The selection is based on uplink measurements and feedback information from a particular mobile station whereto the next downlink frame is to be transmitted.
Abstract:
A method for determining weight factors of antenna beams, the method comprising using at least one directional antenna beam implemented with an antenna array to establish a radio link, forming a radio cell with the antenna beam, dividing the radio cell into at least two different cells by dividing the antenna beam, selecting weight factors of antenna elements of the antenna array such that the antenna element specific sums of weight factors of a radio cell formed with the antenna array and corresponding weight factors of at least one, second radio cell formed with the same antenna array are at least substantially equal within predetermined limits in order to achieve a predetermined power balance between different antenna elements.