Samsung Electronics Co., Ltd.

Yonsei University

Hyo-Yol Park

Yung-Soo Kim

Dong-Ho Kim

Kwang-Soon Kim

Yun-Seok Choi

Keum-Chan Whang

Hee-Won Kang

Sung-Kwon Jo

Tak-Ki Yu

Hwa-Sun You

Ha-Young Yang

Ye-Hoon Lee

Myeon-Gyun Cho

Yon-Woo Yoon

Jae-Won Kang

A method and apparatus are provided for controlling a data rate in a mobile communication system. The method includes changing an offset from a first offset used in a previous packet to a second offset determined based on whether or not the previous packet is successfully received by a second apparatus; determining whether or not a second channel quality in which the second offset is applied is within a range from a minimum quality to a maximum quality; if it is determined that the second channel quality is not within the range, determining that the offset is maintained as the first offset in a current packet; and transmitting, to the second apparatus, the current packet according to a first channel quality in which the first offset is applied.

Apparatus and method for rate control in mobile communication system

Disclosed are an apparatus and system for controlling a data rate in a mobile communication system. The apparatus includes a controller which is configured to update an offset when an error rate of a channel needs to be corrected based on a code rate of a frame, presence/absence of an error through Cyclic Redundancy Check (CRC), and channel state information such as an offset value, and maintain the offset when the code rate of the channel is a maximum value or a minimum value.

Method of estimating a channel in a wireless communication system by obtaining a channel impulse response from a pilot signal included in a received signal; estimating a timing offset with a maximum peak power value for the channel impulse response; and performing a phase compensation using the estimated timing offset and estimating a channel which is applied with the compensated phase.

Method and apparatus for estimating channel using phase compensation in wireless communication system

A method and an apparatus for estimating an offset are provided. The method includes determining one of a frequency offset and a timing offset to be estimated first for pilot symbols detected from a received signal, estimating one of the frequency offset and the timing offset for the pilot symbols according to the determination, compensating for an offset of the pilot symbols based on the estimated offset, and estimating remaining one of the frequency offset and the timing offset which is not estimated for the offset compensated pilot symbols.

Method and apparatus for offset estimation in mobile communication system

A method and an apparatus for transmitting a signal in a communication system are provided. An information vector is encoded according to a Low Density Parity Check (LDPC) encoding scheme, thereby generating an LDPC codeword. Minimum surviving check nodes are reserved for recovery of punctured nodes in the LDPC codeword. A check node is selected having a smallest cost function from among unreserved check nodes. A variable node is selected being unpunctured and having a smallest cost function from among variable nodes connected to the selected check node. The selected variable node is punctured when the selected variable node is not connected to the reserved check node. A stopping set check is performed when the selected variable node is connected to the reserved check node. The variable node is punctured when the stopping set check has been successfully performed. The check node is selected until there remains no variable node to be punctured and puncturing the variable node.

Apparatus and method for signal transmission/reception in a communication system

A method for puncturing a Low Density Parity Check (LDPC). The method includes a) setting a codeword length and the total number of bit nodes to be punctured; b) selecting a check node (or check nodes) with highest priority excluding check nodes completely checked in a current round; c) selecting a bit node (or bit nodes) with a highest priority excluding bit nodes completely checked among bit nodes connected to the selected check node (or check nodes); d) determining whether the selected bit node is a bit node to be punctured, that is, it is not systematic, not set by a puncturing prohibition flag; e) puncturing an associated bit node if the selected bit node is the bit node to be punctured, setting unpunctured bit nodes connected to the selected check node by a puncturing prohibition flag, decreasing the number of remained bit nodes to be punctured by 1 and increasing the number of connected punctured node of associated check node by 1; f) determining whether the number of remaining bits to be punctured is greater than 0; and g) returning to step b) if the number of remaining bits to be punctured is greater than 0, and ending a puncturing process if the number of remaining bits to be punctured is not greater than 0.

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Seoul, South Korea

Hyo-Yol Park