Abstract:
A method for reducing feedback in a mobile communication system is provided to decrease required feedback without a drop in performance for full feedback by presenting an efficiency-based feedback reduction method. An MS(Mobile Station) estimates the average value of allocated subchannels(202). The MS determines the number of subchannels to feed back CQIs(Channel Quality Indicators)(204). The MS judges whether the determined number exceeds the total number of subchannels(206). If the determined number exceeds the total number of subchannels, the MS determines the number of subchannels to feed back CQIs as the total number of subchannels(208). Then the MS feeds back the CQIs of associated subchannels as much as the number of subchannels equivalent to the determined number(214). However, if the determined number is below the total number of subchannels, the MS judges whether the determined number is 0(210). If so, the MS works in detection mode(212).
Abstract:
A method and an apparatus of allocating for dynamic power to control inter-cell interference in multi-cell OFDMA(Orthogonal Frequency Division Multiple Access) systems are provided to enhance the capability of mobile stations positioned at a cell boundary by controlling the inter-cell interference. The amount of channel interference on respective channels, formed by different frequency resources from one another, are measured from signals received from a base station(430). Channel preference degree information, indicating channel preference degree on respective channels, is determined based on the measured channel interference amounts. Channel information including the determined channel preference degree information is fed back to the base station(460). The base station receives data from the base station through channels having allocated power based on the channel preference degree information.
Abstract:
A device for performing bi-casting in a mobile communication system and a method thereof are provided to enable a reference base station **to differently start** data bi-casting start time according to mobile speed of each terminal, thereby reducing backhaul resource consumption as well as generation of backhaul overloads. A mobile speed estimator(303) estimates mobile speed of terminals. A bi-casting threshold value setup unit(307) sets bi-casting threshold values based on the estimated mobile speed. A controller(301) compares the bi-casting threshold values with signal strength of a neighbor base station, and demands bi-casting execution to an upper system if the signal strength of the neighbor base station is larger than the bi-casting threshold values.
Abstract:
본 발명은 통신 시스템에서 매크로 기지국의 핸드오버 방법에 있어서, 상기 매크로 기지국이 복수의 그룹들 각각에 대응되며, 각 그룹에 위치한 이동 단말기들을 위한 핸드오버 가능 기지국들에 관한 정보를 포함하는 복수의 메시지들과, 상기 복수의 그룹들 각각의 위치를 나타내는 그룹 영역 정보를 해당 그룹 내에서 방송하고, 상기 복수의 메시지들 및 상기 그룹 영역 정보를 기반으로 상기 이동 단말기들의 핸드오버를 관리하며, 상기 복수의 그룹들은 복수의 마이크로 기지국들에 대한 서비스 영역들을 그룹화하여 결정된다. 인접 기지국 광고 메시지, 그룹 영역, 위치 정보 추정.
Abstract:
A device and a method for performing handover of a terminal between systems using a different frequency band are provided to reduce time and power needed for scanning by performing unnecessary scanning operation. A terminal transmits an indication signal for informing presence to surroundings after initial access(205). When a handover command message to a small-size base station is received from a base station, the terminal performs a handover procedure to the small-size base station(209).
Abstract:
A method for providing the continuity of the peer-to-peer communication when it is difficult to maintain a service due to the influence of the movement of a terminal and the change of a wireless channel condition and an apparatus therefor are provided. A terminal 1(302) performs P2P data communication with the terminal 2(304) through a P2P connection procedure(308). In case the distant between the terminals becomes larger or a radio channel environment is seriously degraded, because it is impossible to maintain the P2P service with limited transmission power, the terminals periodically monitor whether the P2P service can be continuously used by referring to the signal strength of the other parties(310). If it is determined that the continuity of the P2P service is impossible, the terminal 1 transmits a P2P connection request message(312) to a base station 1(300) to request P2P service relay.