Abstract:
Un método para comunicar información de canal de control en un sistema de comunicación inalámbrica, que incluye transmitir una supertrama que tiene una región de recursos de tiempo-frecuencia que contiene un canal de control de asignación y múltiples elementos de pilotos, por lo menos algunos de, los cuales se asocian con el canal de control de asignación, e indican, en un canal de control de configuración de la supertrama, una característica de los elementos de pilotos asociados con el canal de control de asignación.
Abstract:
A generalized form of cyclic shift diversity is described for use in an OFDM system with multiple transmit antennas. Multiple cyclic shifts are performed for each transmit antenna and the shifted signals are scaled and summed to form a time-domain data stream for each transmit antenna. A cyclic extension is added to each data stream prior to transmission.
Abstract:
A method an apparatus is described for providing feedback for closed-loop transmitting with multiple transmit and receive antennas. The method includes a first step (900) of providing a codebook containing sets of weightings for each data stream of the multiple transmit antennas with each set identified by an index known to a transmitter and a receiver. The same codebook is utilized for any number of data streams up to the number of transmit antennas. A next step (902) includes measuring a composite channel between the transmitter and receiver. A next step (904) includes determining at least one performance metric for each set of weightings in the codebook. A next step (906) includes selecting preferred weightings for each data stream in response to the performance metrics. A next step (908) includes feeding back an index of the preferred weightings to the transmitter for use in subsequent transmissions.
Abstract:
A method and apparatus for performing spatial-division multiple access within a communication system is provided herein. During operation, nodes will return null subspace information along with their channel subspace information. The null subspace is similar to the channel subspace except that the null subspace information directs a base station to the matrix in a predefined codebook that results in minimum power being received at the node. The null subspace for each node is taken into consideration when communicating with a particular node.
Abstract:
Un método para comunicar información de canal de control en un sistema de comunicación inalámbrica, que incluye transmitir una supertrama que tiene una región de recursos de tiempo-frecuencia que contiene un canal de control de asignación y múltiples elementos de pilotos, por lo menos algunos de los cuales se asocian con el canal de control de asignación, e indican, en un canal de control de información de configuración de la supertrama, una característica de los elementos de pilotos asociados con el canal de control de asignación.
Abstract:
A method an apparatus is described for providing feedback for closed-loop transmitting with multiple transmit and receive antennas. The method includes a first step (900) of providing a codebook containing sets of weightings for each data stream of the multiple transmit antennas with each set identified by an index known to a transmitter and a receiver. The same codebook is utilized for any number of data streams up to the number of transmit antennas. A next step (902) includes measuring a composite channel between the transmitter and receiver. A next step (904) includes determining at least one performance metric for each set of weightings in the codebook. A next step (906) includes selecting preferred weightings for each data stream in response to the performance metrics. A next step (908) includes feeding back an index of the preferred weightings to the transmitter for use in subsequent transmissions.