摘要:
Methods and apparatuses are disclosed that determine whether to feedback, and the amount of feedback, with respect to eigenbeam information based upon channel resources. Additionally, methods and apparatuses are disclosed that determine whether to feedback, and the amount of feedback, with respect to eigenbeam information based upon channel information and changes in channel information.
摘要:
Methods and apparatuses are disclosed that determine a type of channel information based upon whether a wireless device is scheduled to receive symbols. In addition, a determination may be as to a number of hop periods to determine the type of channel information. Further, a distance between hop regions may be utilized to determine a type of channel information.
摘要:
Apparatuses and methodologies are described that enhance performance in a wireless communication system using beamforming transmissions. According to one aspect, a set of transmit beams are defined that simultaneously provides for space division multiplexing, multiple-input multiple output (MIMO transmission and opportunistic beamforming. The addition of a wide beam guarantees a minimum acceptable performance for all user devices.
摘要:
Transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are described. For data transmission, the assigned subcarriers and spatial multiplexing order (M) for a receiver are determined, where M≧1. For each assigned subcarrier, M virtual antennas are selected from among V virtual antennas formed with V columns of an orthonormal matrix, where V≧M. V may be selected to achieve the desired spatial diversity order and channel estimation overhead order. Output symbols are mapped to the M virtual antennas selected for each assigned subcarrier by applying the orthonormal matrix. Pilot symbols are also mapped to the V virtual antennas. The mapped symbols are provided for transmission from T transmit antennas, where T≧V. Transmission symbols are generated for the mapped symbols, e.g., based on OFDM or SC-FDMA. Different cyclic delays may be applied for the T transmit antennas to improve diversity.
摘要:
Transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are described. For data transmission, the assigned subcarriers and spatial multiplexing order (M) for a receiver are determined, where M≧1. For each assigned subcarrier, M virtual antennas are selected from among V virtual antennas formed with V columns of an orthonormal matrix, where V≧M. V may be selected to achieve the desired spatial diversity order and channel estimation overhead order. Output symbols are mapped to the M virtual antennas selected for each assigned subcarrier by applying the orthonormal matrix. Pilot symbols are also mapped to the V virtual antennas. The mapped symbols are provided for transmission from T transmit antennas, where T≧V. Transmission symbols are generated for the mapped symbols, e.g, based on OFDM or SC-FDMA. Different cyclic delays may be applied for the T transmit antennas to improve diversity.
摘要:
Apparatus and methods implementing transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are provided. For example, an apparatus is provided that includes a processor configured to allocate different subcarriers to different antennas at different times. A memory is coupled to the processor. The processor can be further configured to map a traffic channel to a specific sequence of the different subcarriers at the different times. The processor can also be further configured to transmit the traffic channel on only one of the different subcarriers at each time in the different times. The processor can be integrated with at least one of a base station and a terminal.
摘要:
Techniques to enhance the performance in a wireless communication system using segments called subbands and using precoding are shown. According to one aspect, the bandwidth for transmission to an access terminal is constrained to a preferred bandwidth which is less than the bandwidth available for transmission to an access terminal and precoding information related to the subcarriers within the constrained bandwidth is provided to a transmitter. The precoding information related to the subcarriers within a constrained bandwidth provides feedback about the forward link channel properties relative to different subbands and may be fed back on a channel associated with the bandwidth.
摘要:
Apparatuses and methodologies are described that enhance performance in a wireless communication system using beamforming transmissions. According to one aspect, the channel quality is monitored. Channel quality indicators can be used to select a scheduling technique, such as space division multiplexing (SDM), multiple-input multiple output (MIMO) transmission and opportunistic beamforming for one or more user devices. In addition, the CQI can be used to determine the appropriate beam assignment or to update the beam pattern.
摘要:
Embodiments are described in connection with enhancing performance in a wireless communication system using codebook technology. According to an embodiment is a method for enhancing performance in a wireless communication environment. The method can include receiving a user preference for a transmission mode, associating the user preference with an entry or entries in a codebook, and assigning the user to a transmission mode corresponding to the entry or entries. The transmission mode can be one of a precoding, space division multiple access (SDMA), SDMA precoding, multiple input multiple output (MIMO), MIMO precoding, MIMO-SDMA and a diversity. Each entry can correspond to a transmission mode.
摘要:
Transmission schemes that can flexibly achieve the desired spatial multiplexing order, spatial diversity order, and channel estimation overhead order are described. For data transmission, the assigned subcarriers and spatial multiplexing order (M) for a receiver are determined, where M≧1. For each assigned subcarrier, M virtual antennas are selected from among V virtual antennas formed with V columns of an orthonormal matrix, where V≧M. V may be selected to achieve the desired spatial diversity order and channel estimation overhead order. Output symbols are mapped to the M virtual antennas selected for each assigned subcarrier by applying the orthonormal matrix. Pilot symbols are also mapped to the V virtual antennas. The mapped symbols are provided for transmission from T transmit antennas, where T≧V. Transmission symbols are generated for the mapped symbols, e.g., based on OFDM or SC-FDMA. Different cyclic delays may be applied for the T transmit antennas to improve diversity.