摘要:
An efficient link adaptive scheme according to a channel status in a broadband wireless communication system is disclosed. In applying an adaptive modulation and coding (AMC) scheme, modulation and coding selection (MCS) subsets are determined from all or part of MCS set in accordance with a service type or channel status, whereby feedback overhead is reduced and efficient link adaptation is performed in conjunction with a downlink power control scheme.
摘要:
A method of transmitting a midamble for channel estimation of multiple antennas performed by a base station in a system having segregated uplink and downlink frequency bands is provided. The method includes transmitting midamble information indicating presence of the midamble within a downlink frame to a user equipment (UE), and transmitting the midamble on a single downlink subframe among at least one downlink subframe included in the downlink frame or on a common zone to the UE by using the multiple antennas. A scheduling overhead of a base station and other overheads can be reduced by decreasing the number of transmissions of a midamble on one downlink frame, and thus limited radio resources can be effectively used.
摘要:
A method for detecting signals based on despreading and a signal transmitting method for the same are provided. Signals are spread according to the size of at least one spreading band, which is determined in consideration of a correlation degree of a frequency band in a communication system. A reception side which receives the signals detects the signals after de-spreading with respect to signals which are spread in a frequency band having a correlation degree equal to or greater than a predetermined level as a spreading band, among the reception signals. Thus, the dimension of the detected signals can be decreased.
摘要:
A method for transmitting a multiple codeword (MCW) in a Multiple Input Multiple Output (MIMO) communication system is disclosed. A method for transmitting a multiple codeword (MCW) in a Multiple-Input Multiple-Output (MIMO) communication system includes performing a channel coding and modulation process for each codeword of the multiple codeword (MCW), multiplying the channel-coded-modulated result by a rotation matrix decided by either a spatial multiplexing rate or a layer (R), and performing a codeword permutation (CP) on the multiple codeword (MCW), performing a MIMO encoding on the multiple codeword (MCW), and transmitting the multiple codeword (MCW) via a multi-antenna.
摘要:
A method of transmitting a pilot method in a multi-antenna system is provided. The method comprises generating a preceding matrix including a preceding vector, the preceding vector being applied to each of data streams to be transmitted, performing preceding procedure for a pilot by using the preceding matrix, and transmitting the precoded pilot, wherein transmission power of the precoded pilot is determined specifically to the each of the data streams. The transmission power of a precoded pilot can be controlled adaptively, individually and independently for each channel to improve channel estimation performance.
摘要:
A data transmission method for multiple users having multiple receive antennas is provided. The method includes selecting a receive antenna among the multiple receive antennas for each user, performing DPC (Dirty Paper Coding) from the multiple transmit antennas to the receive antenna and transmitting a transmission signal on which the DPC is performed. Since DPC is implemented through a receive antenna selected among multiple receive antennas, complexity is not much increased although the DPC is applied to a MIMO system.
摘要:
There is provided a method for placing reference signals in a wireless communication system. The method includes preparing a plurality of sub-frames for a plurality of antennas, placing a reference signal for one sub-frame and placing a reference signal for another sub-frame not to overlap with the reference signal for one sub-frame, wherein the reference signal for one sub-frame and the reference signal for another sub-frame are successively placed on contiguous OFDM symbols or on the contiguous sub-carriers. Channel estimation or data demodulation can be prevented from performance degradation.
摘要:
The present invention relates to a method for transmitting a sounding signal in a multiple input multiple output (MIMO) wireless mobile communication system. The method comprises: a step in which a terminal that supports a plurality of transmitting antennas receives, from a base station, at least one piece of uplink sounding transmission control information; and a step of transmitting a sounding signal using the received uplink sounding transmission control information, wherein said sounding transmission control information includes periodicity information for periodically repeating the transmission of the sounding signal, and a piece of antenna designation information for designating an antenna from among the plurality of transmitting antennas to be used in transmitting the sounding signal.
摘要:
A feedback method for performing a feedback by using a codebook in Multiple Input Multiple Output (MIMO) system includes receiving, by the mobile station, a MIMO mode type information, generating feedback information by using the codebook selected according to the MIMO mode type information, and transmitting the feedback information to the base station. The codebook includes a SU-MIMO codebook and a MU-MIMO codebook, and the MU-MIMO codebook is formed by extracting codebook elements from the SU-MIMO codebook. As a result, the method maximizes a system throughput simultaneously while effectively reducing an amount of feedback information.
摘要:
A pilot transmission method in a wireless communication system is provided. The method includes: transmitting a first pilot for channel measurement through a first transmission section; and transmitting a second pilot for channel measurement through a second transmission section which is subsequent in time to the first transmission section, wherein the first transmission section and the second transmission section include a plurality of sub-bands, parts of the plurality of sub-bands use predetermined precoding whereas the remaining sub-bands use non-predetermined precoding, and any one of the first pilot and the second pilot is carried only on a sub-band which uses the predetermined precoding whereas the other pilot is carried on the entirety of the plurality of sub-bands.