摘要:
A method and apparatus of a base station (BS) perform uplink (UL) random access in a wireless communication system. Random access channel information is determined on each of a plurality of frames constituting a superframe, and a control message comprising the random access channel information is broadcasted. A method and apparatus of a mobile station (MS) perform UL random access in a wireless communication system. A control message comprising random access channel information is received. A frame for minimizing a collision during a contention-based random access is selected based on the random access channel information. For data to be transmitted using the selected frame, it is determined whether the information to be transmitted is an access class with equal or higher priority to a received access class comprised in the random access channel information. A contention-based random access bandwidth request is transmitted to the BS for the data to be transmitted.
摘要:
Provided are an ARQ apparatus and method for a multihop system in a broadband wireless access communication system. The ARQ method of a relay includes determining if the relay successfully receives specific data from a source and transmitting the specific data to a destination; receiving feedback data from the destination and determining if the destination successfully receives the specific data; generating feedback data including data indicating if the relay and the destination successfully receive the specific data, and outputting the feedback data to the source; and retransmitting the specific data, when the relay successfully receives the specific data but the destination fails to receive the specific data. Accordingly, when the MH-BTS successfully receives the data from the source but the destination fails to receive the data, the source does not retransmit same data to the MH-BTS.
摘要:
A common operating set including a plurality of cells may be set, and common radio resources may be allocated to enable the plurality of cells to perform a multi-cell common operation. Unique uplink radio resources may be allocated to each of terminals in the common operating set within the common radio resources, and each of the terminals may transmit corresponding uplink feedback information to a plurality of base stations based on corresponding unique uplink radio resources. Accordingly, each of the base stations may recognize information associated with a wireless environment between each of terminals and a corresponding base station.
摘要:
Disclosed herein is a polymer substrate for a flexible display, comprising a reticular superelastic alloy structure and/or an annular superelastic alloy structure therein. The polymer substrate has an improved flexibility because the superelastic alloy structure is embedded therein.
摘要:
An apparatus and method for exchanging frequency bands used by a plurality of base stations are provided. A base station for exchanging frequency bands includes a receiving unit to receive first quiet time duration information of an adjacent base station, a frequency band measuring unit to determine first frequency band measuring information with respect to a first frequency band used by the adjacent base station based on the first quiet time duration information, a frequency band exchange-determining unit to determine whether to exchange frequency bands with each other based on the first frequency band measuring information, and a transmitting unit to transmit data to a terminal using the first frequency band according to the determined result.
摘要:
A seamless handoff system and method reduces delay and packet loss during handoff of user equipment (UE) from a Wireless Local Area Network (WLAN) network to a Universal Mobile Telecommunication System (UMTS) network. The handoff system and method performs pre-registration and pre-authentication processes before the occurrence of a handoff, buffers packets being delivered to a UE during a handoff period, and forwards the buffered packets to the UE after completion of the handoff, thereby reducing packet loss that can occur during handoff.
摘要:
A method of reporting channel state information by a Mobile Station (MS) in a mobile communication system is disclosed. The method includes measuring a state of a downlink channel for the entire frequency band, determining a first Modulation and Coding Scheme (MCS) level corresponding to the measured channel state, and reporting the determined MCS level to a Base Station (BS).
摘要:
Provided is an apparatus and method for transmitting/receiving signals in a communication system. A base station allocates a quasi-dedicated control channel (QDCCH) to a first mobile station (MS), and allocates the QDCCH allocated to the first MS, to a second MS for a preset time. An MS receives a QDCCH allocated from the base station. If there is data to transmit to the base station, the MS determines whether the QDCCH is allocated to another MS different from the MS. If it is determined that the QDCCH is allocated to the MS itself, the MS transmits the data to the base station over the QDCCH.
摘要:
Provided is an apparatus and method for enhancing the link performance of a multicast service for UEs in a wireless system. In the method, multicast data received in an Nth frame is recovered using systematic packets. When the recovery fails, parity packets are received in an (N+1)th frame and are used to recover the multicast data. When the recovery fails again, an autonomous handover is performed to receive parity packets from a neighboring cell or sector, which are used to recover and the multicast data.
摘要:
A method is provided for transmitting a packet data unit (PDU) by a transmitter in a wireless mobile communication system. The method includes determining at least one desired transmission PDU, determining a modulation scheme corresponding to the number of PDUs, and transmitting a first indicator value indicating the number of PDUs and the modulation scheme, transmitting the PDUs, receiving a second indicator value indicating a reception state of the PDUs, from a receiver that receives the PDUs, determining a new PDU or a retransmission PDU according to the second indicator value, and determining a modulation scheme corresponding to the number of the determined PDUs, and transmitting a third indicator value indicating the number of PDUs and the modulation scheme, and the corresponding PDUs.