Abstract:
본 발명은, 멀티유저 다중입출력(MU-MIMO) 방식으로 신호를 송수신하는 환경에서, 단말로부터 수신되는 코드북 기반의 피드백정보로 인한 오버헤드를 감소시키는 효과 및 피드백정보의 정확성을 높여 MU-MIMO 성능까지 개선하는 효과를 모두 달성할 수 있는 기지국장치 및 기지국장치의 동작 방법을 제안한다.
Abstract:
PURPOSE: Electric power control method and system thereof for a femtocell are provided to make all network users receive support greater than a specific level of service by appropriately controlling transmission electric power used in a femtocell. CONSTITUTION: An information acquisition unit (410) acquires information in a network environment. A scheduling unit (420) calculates the minimum transmission rate of a macrocell by performing Max-Min scheduling. A broadcasting unit (430) broadcasts the minimum transmission rate of the macrocell to the femtocell. An electric power control unit (440) sets up a target transmission rate using the minimum transmission rate broadcasted to the femtocell. The electric power control unit performs power control. [Reference numerals] (400) Femtocell electric power control system; (410) Information acquisition unit; (420) Scheduling unit; (430) Broadcasting unit; (440) Electric power control unit; (450) Alarm unit
Abstract:
본 발명은 다중사용자 MIMO 릴레이 시스템에서 단대단 레벨 SVD 전송기법에 관한 것으로, 본 발명에 따르면, MU(Multi-User)-MIMO(Multiple-Input and Multiple-Output) 릴레이 시스템에서 송신단-릴레이, 릴레이-사용자 두 개의 채널을 곱한 채널을 특이값 분해하고, 그 값을 기반으로 한 프리코딩 행렬을 이용하여 송신단-사용자 간 MU-MIMO 릴레이 채널을 다수의 독립된 SU(Single-User)-MIMO 채널로 분해하며, 분해된 단대단 SU-MIMO 채널을 SVD(singular value decomposition)-MIMO 기법을 이용하여 간섭이 없는 공간다중화 신호를 전송하는 방법이 제공됨으로써, MU-MIMO 릴레이 채널에 있어서 릴레이-사용자 채널에서 발생하는 간섭을 프리코딩을 이용하여 제거하며, 낮은 비용과 복잡도를 가지는 AF(amplify and forwarding) 릴레이를 이용하여 전송용량을 높일 수 있다.
Abstract:
PURPOSE: A radio resource management system in heterogeneous networks is provided to maximize the minimum process amount among all users like obtaining a max-min fairness. CONSTITUTION: A data rate calculation unit(610) calculates data rate of each user terminal in an OFDMA(Orthogonal Frequency Division Multiple Access) network and a WLAN(Wireless Local Area Network). A user terminal alignment unit(620) aligns a plurality of user terminals. A network selection group determination unit(630) selects a network selection group in which the minimum data rate is searched among all network selection groups of user terminals. A resource allocation unit(640) assigns the resources to each user terminal.
Abstract:
PURPOSE: A method for improving performance using a relay uplink of a 3gpp LTE system based hybrid OFDMA/SC-FDMA and a mobile communication terminal thereof are provided to enhance cell coverage by transmitting data to the communication net using a relay terminal. CONSTITUTION: A relay application determining unit(150) determines the operating status of a relay according to the movement of a mobile communication terminal toward a cell boundary area. A relay selection unit(160) selects a mobile communication terminal having a high performance value among the mobile communication terminals positioned near the mobile communication terminal as a relay terminal.
Abstract:
A method for eliminating the interference of a piconet using intelligent channel time allocation is provided to eliminate the interference generated in a common region among the piconets by using the intelligent channel time allocation comprising public channel time allocation and a normal channel time allocation. A first piconet coordinator adjusts a superframe to simultaneously a first piconet and a second piconet which have a common region, and the first and the second piconet coordinators transmit a beacon signal comprising superframe adjusting information of the common region to all devices(S100). The DEV which receives the beacon signal from the first or the second piconet coordinator determines whether it is contained in the common region, and the device contained in the common region requests private time channel allocation of a channel time(S200). The first and the second piconet coordinators allocate the channel time according to the channel time request(S300).