摘要:
During operation, the choice of the initial ranging code (sometimes referred to as a ranging preamble code, or a random-access preamble) at the mobile station is associated with a PMI feedback to be signaled to the base station during the initial ranging. More particularly, during initial system access a ranging code is transmitted by the mobile station to the base station. The mobile station chooses one of the available ranging codes based on the channel conditions and associates the ranging code with channel feedback information. The ranging code is then transmitted to the base station, and provides the base station with the channel feedback information.
摘要:
In an OFDM communication system, wherein a frequency bandwidth is divided into multiple Physical Resource Units (PRUs), a Frequency Partitioning Configuration Module (FPCM) is provided that configures a physical layer for use in multiple coverage areas. The FPCM divides the PRUs into a first group, for frequency selective allocations, and a second group, for frequency diverse allocations. The FPCM subdivides each of the two groups into multiple sets of PRUs, maps the sets of PRUs from the first group to consecutive PRUs allocated for contiguous segment allocation (CS-PRUs), and maps the sets of PRUs from the second group to consecutive PRUs allocated for distributed segment allocation (DS-PRUs). The FPCM permutes the DS-PRUs and allocates the CS-PRUs and the permuted DS-PRUs to at least one frequency partition.
摘要:
In an OFDM communication system, wherein a frequency bandwidth is divided into multiple Physical Resource Units (PRUs), a Frequency Partitioning Configuration Module (FPCM) is provided that configures a physical layer for use in multiple coverage areas. The FPCM divides the PRUs into a first group, for frequency selective allocations, and a second group, for frequency diverse allocations. The FPCM subdivides each of the two groups into multiple sets of PRUs, maps the sets of PRUs from the first group to consecutive PRUs allocated for contiguous segment allocation (CS-PRUs), and maps the sets of PRUs from the second group to consecutive PRUs allocated for distributed segment allocation (DS-PRUs). The FPCM permutes the DS-PRUs and allocates the CS-PRUs and the permuted DS-PRUs to at least one frequency partition.
摘要:
A method for communicating control channel information in a wireless communication system, including transmitting a super-frame having a time-frequency resource region containing an allocation control channel and multiple pilot elements, at least some of which are associated with the allocation control channel, and indicating, in a configuration information control channel of the super-frame, a characteristic of the pilots elements associated with the allocation control channel.
摘要:
A method for communicating control channel information in a wireless communication system, including transmitting a super-frame having a time-frequency resource region containing an allocation control channel and multiple pilot elements, at least some of which are associated with the allocation control channel, and indicating, in a configuration information control channel of the super-frame, a characteristic of the pilots elements associated with the allocation control channel.
摘要:
A method for communicating control channel information in a wireless communication system, including transmitting a super-frame having a time-frequency resource region containing an allocation control channel and multiple pilot elements, at least some of which are associated with the allocation control channel, and indicating, in a configuration information control channel of the super-frame, a characteristic of the pilots elements associated with the allocation control channel.
摘要:
A method and apparatus for providing channel feedback is provided herein. During operation a covariance matrix at time t (R) is calculated as a function of a received downlink signal. Matrix Ct is also calculated and is based on a previous quantized covariance matrix (Rqt-1), the covariance matrix (R) at time t, and a forgetting factor (γ) that is applied to Rqt-1. The Ct is then used to create a DERC feedback message (signal or waveform) and may be transmitted with pilots on a proper feedback channel to a base unit. The base unit receives the feedback (Ct) as a DERC waveform on a proper feedback channel. The base unit uses non-coherent or coherent detection to detect the DERC values send by the remote unit and uses the DERC values with a previous quantized covariance matrix estimate, a forgetting factor, and a weighting value to compute a covariance matrix estimate to use for beamforming. The base unit then uses the covariance matrix estimate to determine appropriate channel beamforming weights, and instructs transmit beamforming circuitry to use the appropriate weights.
摘要:
A method and apparatus for providing channel feedback is provided herein. During operation a covariance matrix at time t (R) is calculated as a function of a received downlink signal. Matrix Ct is also calculated and is based on a previous quantized covariance matrix (Rqt-1), the covariance matrix (R) at time t, and a forgetting factor (γ) that is applied to Rqt-1. The Ct is then used to create a DERC feedback message (signal or waveform) and may be transmitted with pilots on a proper feedback channel to a base unit. The base unit receives the feedback (Ct) as a DERC waveform on a proper feedback channel. The base unit uses non-coherent or coherent detection to detect the DERC values send by the remote unit and uses the DERC values with a previous quantized covariance matrix estimate, a forgetting factor, and a weighting value to compute a covariance matrix estimate to use for beamforming. The base unit then uses the covariance matrix estimate to determine appropriate channel beamforming weights, and instructs transmit beamforming circuitry to use the appropriate weights.
摘要:
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.
摘要:
Channel information feedback takes place by calculating channel information to feed back to the base station. The channel quality information is spread by a remote unit with spreading codes from mutually unbiased bases and transmitted to the base station. The advantages of spreading the feedback channel are that multiple mobiles can send their feedback on the same time-frequency resources making the feedback very efficient and also improving feedback performance through orthogonal spreading which gives a spreading gain above noise and interference. Using the spreading codes from mutually unbiased bases can reduce interference across sectors.