摘要:
An apparatus and a method for interference cancellation in a broadband wireless communication system are provided. A receiving apparatus includes an estimator, a channel compensator, and a demodulator. The estimator estimates channels of a desired signal and at least one interference signal, estimates noise, calculates a mean interference power of each interference signal, and calculates a mean noise power. The channel compensator channel-compensates burst data. The demodulator calculates a noise variance value by adding the mean noise power to the at least one mean interference power and creates Log Likelihood Ratio (LLR) by demodulating the channel-compensated data.
摘要:
A method and apparatus for transmitting and receiving a Hybrid Automatic Repeat reQuest (HARQ) burst in a communication system are provided. A transmitter obtains at least one Protocol Data Unit (PDU) according to a decoding order of a receiver which supports a HARQ mode. The receiver controls an order of at least one HARQ burst using burst information including a HARQ Channel IDentifier (ACID).
摘要:
A method and Mobile Subscriber Station (MSS) are provided for transmitting Channel Quality Information (CQI) in a wireless communication system using an Orthogonal Frequency Division Multiple Access (OFDMA) scheme. A Carrier to Interference and Noise Ratio (CINR) of at least two bands are measured; each of the at least two bands including a plurality of adjacent subcarriers for a band Adaptive Modulation and Coding (AMC) operation. A Report Response (REP-RSP) message including first information related to the measured CINR is sent. Second information related to a differential CINR of the at least two bands is sent via a Channel Quality Information Channel (CQICH).
摘要:
A transmitter for minimizing a PAPR in OFDM communication system. The transmitter includes: a precoder for coding input symbols so that a signal rotation is generated, and generating a complex vector including the coded symbols; an encoder for performing a frequency-space mapping for the symbols generated as the complex vector according to a predetermined scheme; a random mapper for randomly mapping the symbols for which the frequency-space mapping has been performed on a frequency plane through at least one transmit antenna; an Inverse Fast Fourier Transform (IFFT) unit for performing an IFFT for the symbols for which the frequency-space mapping has been performed; and a gradient algorithm unit for receiving IFFTed signals from the IFFT unit and reducing the PAPR.
摘要:
Disclosed is a method for using various multiple antenna schemes in a baseband wireless access system is provided. According to the method, a downlink MAP message is constructed in order to support various multiple antenna schemes based on a multiple-input multiple output (MIMO), which is one of the multiple antenna schemes, so that compatibility with exiting MIMO technology having no MIMO feedback can be achieved and overhead occurring in transmission of an MAP information element can be reduced. Further, it is possible to efficiently support spatial multiplexing technology capable of transmitting multiple layers having different modulation and coding in a MIMO system.
摘要:
A method for allocating a frequency to a subscriber station (SS) in handover operation in an Orthogonal Frequency Division Multiple Access (OFDMA) system. In the method, the SS checks safety channel frequencies for a target base station (BS), generates a safety channel frequency request message for requesting allocation of the checked safety channel frequencies, and transmits the safety channel frequency request message. Upon receiving the safety channel frequency request message from the SS, a serving BS allocates frequencies for a requested channel, and transmits an allocation message with the frequency allocation information to the SS. The serving BS transmits a channel allocation request message to the target BS according to the frequency allocation information. Upon receiving the channel allocation request message, the target BS allocates the safety channel frequencies to the SS.
摘要:
A space-time block coding (STBC) apparatus and method for a transmitter with four Tx antennas is provided. An input symbol sequence is transmitted through the four Tx antennas in a predetermined method based on feedback information received from a receiver, thereby improving the performance of an STBC.
摘要:
An apparatus and method for preventing power imbalance between antennas in a closed-loop MIMO system are provided. In a transmitter in the MIMO system, a first calculator generates a vector by multiplying a transmission vector by a beamforming matrix and a second calculator generates a plurality of antenna signals by multiplying the vector by a predetermined phase rotation matrix.
摘要:
A method of mapping Space-Time Coding (STC) data to subcarriers in a broadband wireless communication system using multiple antennas is provided. Transmission symbols are encoded according to a predetermined space-time coding matrix and the coded data symbols are mapped to time-space-subcarriers according to a mapping rule determined by the space-time coding matrix.
摘要:
A space-time-frequency block coding apparatus and method in a transmitter with three transmit (Tx) antennas are provided. An input symbol sequence is transmitted through three Tx antennas according to a permutation method using a selected transmission matrix in order to improve the performance of an STFBC.