摘要:
A method and system for supporting multiple hybrid automatic repeat request (H-ARQ) processes per transmission time interval (TTI) are disclosed. A transmitter and a receiver include a plurality of H-ARQ processes to transmit and receive multiple transport blocks (TBs) simultaneously per TTI. The transmitter generates a plurality of TBs and assigns the TBs to multiple H-ARQ processes. The transmitter sends control information for the TBs and H-ARQ processes associated with the TBs to the receiver. The transmitter then sends the TBs using multiple H-ARQ processes simultaneously per TTI. After receiving the TBs, the receiver sends feedback to each of the TBs indicating successful or unsuccessful receipt of each of the TBs to the transmitter. The control information and the feedback may be sent via a layer 1 or layer 2/3 control part.
摘要:
A multiple-input multiple-output (MIMO) receiver includes a MIMO decoder, a pre-scaling unit, a demapper, and a post-scaling unit. The MIMO decoder performs a MIMO decoding on received signals to decouple a plurality of symbols transmitted via a plurality of data streams. Both pre-demapping scaling and post-demapping scaling are performed to improve the performance of the receiver. A pre-scaling coefficient is applied to the symbols by the pre-scaling unit to generate pre-scaled symbols. The pre-scaled symbols are converted to soft bits by the demapper. The post-scaling unit then applies a post-scaling coefficient to the soft bits. The post-scaling coefficient is a signal-to-interference and noise ratio (SINR). Cross interference is taken into account in post-demapping scaling to obtain more accurate soft bits for subsequent decoding. The present invention is applicable to both a multi-carrier system, (such as orthogonal frequency division multiplexing (OFDM)), and a single carrier system.
摘要:
Tokens/keys are produced for wireless communications. These tokens/keys are used for watermarks, signature insertion, encryption and other uses. In one embodiment, contextual information is used to generate tokens/keys. The tokens/keys may be derived directly from the contextual information. The contextual information may be used in conjunction with other information to derive the tokens/keys. Tokens/keys may be exchanged between transmit/receive units. The exchange of these tokens/keys may be encrypted.
摘要:
A method and apparatus for feedback in a wireless transmit receive unit (WTRU) includes transmitting feedback over an aggregate of predefined control channel elements (CCEs) wherein the feedback is one of a channel quality indicator (CQI), a precoding matrix index (PMI) or a rank index.
摘要:
A method and apparatus for reducing a peak-to-average power ratio (PAPR) in a multiple-input multiple-output (MIMO) wireless communication system are disclosed. Transmit beamforming or precoding is performed on transmit symbols based on a channel matrix. For feedback, channel matrices may be averaged over multiple subcarriers and the averaged channel matrices may be further quantized. In order to reduce the PAPR, amplitude clipping may be performed on the symbols after the transmit processing. The amplitude clipping may be performed by hard clipping, soft clipping, or smooth clipping.
摘要:
A method for transmitting feedback information for a wireless transmit receive unit (WTRU) includes multiplexing the feedback information with an uplink shared channel, mapping the multiplexed feedback information to orthogonal frequency division multiplex (OFDM) symbols and transmitting the feedback information to an e Node B. The method also includes multiplexing the feedback information with the uplink shared channel using distributed frequency division multiplexing (FDM), mapping the feedback information to a first OFDM symbol, and distributing the mapped feedback information equidistantly across the transmission bandwidth.
摘要:
A method and system is disclosed for enhancing reception of wireless communication signals. A beam pattern including at least one set of beams is generated. Where the beam pattern includes at least two sets of beams, the beam sets may be offset with respect to each other and alternated to enhance reception. Beams may be selected for data processing based on a signal-to-noise ratio (SNR) and may be maximal-ratio combined where signals from a single WTRU are detected within more than one beam and are used for data processing.
摘要:
A multiple-input multiple-output (MIMO) receiver includes a MIMO decoder, a pre-scaling unit, a demapper, and a post-scaling unit. The MIMO decoder performs a MIMO decoding on received signals to decouple a plurality of symbols transmitted via a plurality of data streams. Both pre-demapping scaling and post-demapping scaling are performed to improve the performance of the receiver. A pre-scaling coefficient is applied to the symbols by the pre-scaling unit to generate pre-scaled symbols. The pre-scaled symbols are converted to soft bits by the demapper. The post-scaling unit then applies a post-scaling coefficient to the soft bits. The post-scaling coefficient is a signal-to-interference and noise ratio (SINR). Cross interference is taken into account in post-demapping scaling to obtain more accurate soft bits for subsequent decoding. The present invention is applicable to both a multi-carrier system, (such as orthogonal frequency division multiplexing (OFDM)), and a single carrier system.
摘要:
A system and method for automatic gain control for a wireless transmit and receive unit in a time-slotted communications system includes initializing an automatic gain control loop, sampling a received signal, and estimating the power of the received signal. The estimated power of the received signal is compared with a reference power level and an error signal is generated based upon the difference between the estimated power and the reference power level. The error signals generated by a plurality of received signals are accumulated in an accumulator, and the value of the accumulator is looked up in a table to locate a control word for an attenuator. The control word is then passed to the attenuator to adjust the gain.