Abstract:
Disclosed is a method for controlling an operational state of a medium access control layer in a broadband wireless access communication system. The method includes the steps of performing an uplink access of a contention-based scheme to an access point using resources required to perform the uplink access according to the contention-based scheme when data to be transmitted in an access state is detected, and being allocated resources required to perform an uplink access of a contention-free scheme from the access point in a case of failing in the uplink access of the contention-based scheme; and performing a state transition from the access state into the traffic state in a case of having been allocated the resource required for the contention-free scheme, and performing the uplink access of the contention-free scheme to the access point using the allocated resource in the traffic state.
Abstract:
Dynamically allocating a frame cell (FC)/subchannel in a mobile communication system by an access point that receives channel quality information (CQIs) fed back from access terminals, determines a modulation and coding scheme (MCS) to be applied to the access terminals based on the CQIs, and if access terminals whose FCs/subchannels must be changed are detected from the access terminals, sends an FC/subchannel change request to an access router. The access router allocates an FC/subchannel set by selecting a number of FCs/subchannels according to the FC/subchannel change request, and transmits information on the allocated FC/subchannel set to the access point. The access point selects and allocates a particular FC/subchannel from among FCs/subchannels in the FC/subchannel set information to the access terminals whose FCs/subchannels must be changed, based on CQIs last received from the access terminals.
Abstract:
An apparatus and method for generating an RS SCH in a wireless communication system are provided, in which a base station checks a BS SCH sequence and a mask sequence, and generates an RS SCH sequence by XOR-operating the BS SCH sequence and the mask sequence.
Abstract:
Provided is an apparatus and method for providing a synchronous relay service in a multi-hop relay BWA communication system. In the method, a BS-MS link subframe and an RS-MS link subframe are configured for a first section of a subframe in an ith frame. At least one of a BS-RS link subframe, an RS-RS link subframe and an RS-MS link subframe is configured for a second section of a subframe in the ith frame. The BS-MS link subframe and the RS-MS link subframe are configured for a first section of a subframe in an (i+1)th frame. At least one of the BS-RS link subframe, the RS-RS link subframe and the RS-MS link subframe is configured for a second section of a subframe in the (i+1)th frame.
Abstract:
Apparatus and method for transmitting and detecting subchannel constitution scheme information in a multihop relay Broadband Wireless Access (BWA) communication system. The method includes determining a subchannel constitution scheme for fixing a start zone of BW-RS link according to channel information (e.g., channel condition information, interference, and mobility), transmitting determined subchannel constitution scheme information of the start zone using a FCH preamble, detecting physical channel signals of subchannel constitution schemes from the received FCH preamble, checking preset codes, and detecting the subchannel constitution scheme of the start zone using the detected physical channel signals of the subchannel constitution schemes and the codes. The subchannel constitution scheme of the BS-RS link can be adaptively applied based on the channel information.
Abstract:
A signal transmission/reception apparatus of a communication system. The signal transmission apparatus receives an information vector, encodes the information vector into a structured Low Density Parity Check (LDPC) codeword using a structured LDPC coding scheme, and transmits the generated structured LDPC code to the signal reception apparatus. Then the signal reception apparatus receives a signal, and detects an information vector by decoding the received signal using a decoding scheme corresponding to the structured LDPC coding scheme used in the signal transmission apparatus.
Abstract:
An apparatus and method for supporting an optimized network reentry procedure in a multihop relay Broadband Wireless Access (BWA) communication system are provided. The communication method for an RS in a multihop relay cellular communication system, includes receiving a HO-notify message, which contains information of an MS handed over to the RS, from a Base Station (BS); and performing an optimized network reentry procedure with the MS using the MS information of the HO-notify message. By defining the RS-BS signaling to provide the RS with information as to the MS handed over to the RS, the optimized network reentry procedure can be carried out between the RS being the target node and the MS.
Abstract:
An apparatus and method for transparently relaying a signal using a plurality of frequency bands in a multi-hop relay cellular network are provided, in which a Relay Station (RS) communicates with a Base Station (BS) via a relay link in a first frequency band and communicates with a Mobile Station (MS) within the sub-cell of the RS via a sub-cell link in a second frequency band different from the first frequency band.
Abstract:
A method and system for acquiring information about neighbor base stations (BSs) and neighbor relay stations (RSs) in a multi-hop relay broadband wireless access communication system are provided. In the method, a serving BS collects information about the neighbor BSs and the neighbor RSs, generates a message including the collected information, and transmits the message to a serving RS and an MSS directly communicating with the serving BS. The serving RS transmits the message to an MSS communicating with the serving BS via the serving RS.
Abstract:
An apparatus and method for determining a vertical handoff for a node supporting a WLAN and an IEEE 802.16 communication system are provided. Reception of a handoff request message from the node is monitored, an expected change in the total throughput of the WLAN in the case where the node is connected to the WLAN is calculated and compared with zero, and if the throughput change is equal to or greater than zero, the handoff request of the node is acknowledged and the node is handed off to the WLAN.