Lg-ericsson Co., Ltd.

Other

Lg Electronics Inc.

Ericsson-lg Co., Ltd.

Hee Gul Park

Sung Lark Kwon

Hyuck Chan Kwon

Jung Seung Lee

Byoung Seong Park

Dong Joo Park

Jae Won Jang

Hoo Young Jeong

Young Kwon Ryu

Hong Jik Kim

Jin Ho Choi

Yoon Oh Yang

Tan Joong Park

Hoo Young Neuti Maeul Jugong Jeong

Dong Joo Neuti Maeul Jugong Park

Embodiments of the present invention may provide an apparatus and a method for transmitting and receiving a random access channel (RACH) in a single carrier-frequency division multiple access (SC-FDMA) system. A frequency domain RACH signal may be mapped to a localized sub-frequency band of an entire frequency band available to the SC-FDMA system. A guard band including at least one sub carrier may be allocated between the RACH signal band and other channel signal bands. A guard time may be allocated between the RACE signal and other channel signals in the time domain. The RACH signal may include a short message including information related to a mobile station. The RACE signal may be detected in a frequency based method, a time based method or a sliding matched filter based method. Receiver complexity can be decreased if the RACH signal includes a CAZAC code sequence for a preamble. In such a case, a receive delay may be simply calculated and then adjusted more accurately.

Apparatus and method for transmitting and receiving a RACH signal in SC-FDMA system

Embodiments of the present invention may provide an apparatus and a method for transmitting and receiving a random access channel (RACH) in a single carrier-frequency division multiple access (SC-FDMA) system. A frequency domain RACH signal may be mapped to a localized sub-frequency band of an entire frequency band available to the SC-FDMA system. A guard band including at least one sub carrier may be allocated between the RACH signal band and other channel signal bands. A guard time may be allocated between the RACH signal and other channel signals in the time domain. The RACH signal may include a short message including information related to a mobile station. The RACH signal may be detected in a frequency based method, a time based method or a sliding matched filter based method. Receiver complexity can be decreased if the RACH signal includes a CAZAC code sequence for a preamble. In such a case, a receive delay may be simply calculated and then adjusted more accurately.

An apparatus and a method for interference cancellation using a multi-user multiple input multiple output (MU-MIMO) scheme in a single carrier frequency division multiple access (SC-FDMA) system are disclosed. Received data of every terminal are classified into first received data and second received data. The first received data has lower reliability and the second received data has higher reliability than the first received data. The second received data is transmitted to an upper layer. Interference signals are formed with the second received data based on a channel estimation value. The interference signals are removed from the first received data, and the interference signal free first received data is transmitted to the upper layer.

Interference cancellation with MU-MIMO scheme in SC-FDMA system

Apparatus and method for determining a fixed point in a mobile communication system are disclosed. An initial fixed point is set through simulation and a saturation for an output of a target device is compared with a reference saturation. Then, the position of the initial fixed point is adaptively changed according to the change in the output range of the target device. Therefore, when a floating point is converted into a fixed point, the performance of the system can be improved while the complexity of the hardware can be reduced.

Apparatus and method for determining fixed point in mobile communication system

An adaptive beamforming apparatus and method of an array antenna in a communication system. First, a tentative symbol decision value is obtained by processing a traffic signal vector, and a final updated coefficient value is obtained by performing a least mean square (LMS) algorithm at least once with respect to the tentative symbol decision value and a pilot signal vector on the assumption that the tentative symbol decision value is a transmitted symbol value. Then an adaptive beam which corresponds to a final symbol decision value is formed using the traffic signal vector and the final updated coefficient value.

Adaptive beamforming method in an IMT-2000 system

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Kimpo, South Korea

Hee Gul Park