摘要:
Systems and methodologies are described that facilitate estimating transmit covariance from evaluation of a channel (e.g., forward link channel, reverse link channel, . . . ) to be utilized in linear precoding for multiple-input multiple-output (MIMO) wireless communication systems. Predefined codebooks that include any number of precoding matrices may be modified based upon transmit covariance estimations to yield improved precoding performance. Further, channel related feedback may be generated and analyzed by utilizing the modified codebooks.
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:
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:
Systems and methodologies are described that facilitates computing a precoding index which correlates to a precoding matrix within a codebook. According to various aspects, systems and/or methods are described that facilitate computing an effective signal-to-noise ratio (SNR). Such systems and/or methods may further facilitate selecting a precoding matrix and a corresponding precoding index. Such systems and/or methods may still further facilitate employing the precoding matrix in a MIMO wireless communication system.
摘要:
Techniques for transmitting data with limited channel information are described. A transmitter (e.g., a base station) obtains channel information for a subset of multiple antennas used for data reception at a receiver (e.g., a terminal). The channel information may include at least one channel response vector for at least one antenna, which is a subset of the multiple antennas at the receiver. The transmitter derives multiple eigenvectors based on the channel information, e.g., using pseudo eigen-beamforming. The transmitter selects at least one eigenvector from among the multiple eigenvectors and transmits data with the selected eigenvector(s). The transmitter may select and use different subsets of eigenvector(s) in different time intervals. The transmitter may arrange the multiple eigenvectors into multiple sets based on their eigenvalues, select at least one set based on a MIMO transmission rank, and select one eigenvector from each set.
摘要:
Systems and methodologies are described that facilitate generating and/or utilizing explicit and implicit feedback related to a forward link channel for linear precoding in a time division duplex (TDD) multiple-input multiple-output (MIMO) system. Implicit feedback may be provided by estimating a reverse link channel, which may be substantially similar to at least a portion of the forward link channel (e.g., based upon reciprocity). Moreover, explicit feedback may be yielded by quantizing at least part of an estimate of the forward link channel (e.g., utilizing vector and/or scalar quantization).
摘要:
Methods and apparatuses are disclosed for providing flexible channel information feedback. In some cases this may be according to reporting types assigned by one or more sectors, with different reporting types for each sector. In other cases, a reporting mode is determined to determine the reporting types to be utilized.
摘要:
Methods and apparatuses are disclosed for providing flexible channel information feedback. In some cases this may be according to reporting types assigned by one or more sectors, with different reporting types for each sector. In other cases, a reporting mode is determined to determine the reporting types to be utilized.
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:
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.