Abstract:
PURPOSE: An RIO(Random Early Detection with in and Out) method and an RIO-DC(DeCoupled) method are provided to evaluate buffer management methods of AF(Assured Forwarding) PHB(Per Hop Behavior) by comparing a performance between the RIO method and the RIO-DC method. CONSTITUTION: Average transmission rates required by a user are confirmed. A predetermined bandwidth is allocated in each sub-class of a guarantee type service for the confirmed average transmission rate by dividing delay time according to traffic information in each flow. A variable value is set based on a buffer size determined according to a bandwidth rate in a network topology and each sub-class of the guarantee type service.
Abstract:
PURPOSE: A signum function based frequency offset estimation method is provided to reliable estimation performance in various noise environments. CONSTITUTION: Receiving reception signal(S110), a complex sign signal(S120) is obtained from the reception signal. Correlation between samples is calculated using a correlation function(S130), a frequency offset estimation value(160) is calculated by performing angle calculation(S140) on the correlation. At this time, a predetermined constant is multiplied with the angle calculation result(S150). [Reference numerals] (S110) Reception signal; (S120) Sign signal; (S130) Correlation function; (S140) Angle calculation; (S160) Estimation value
Abstract:
PURPOSE: A fairness improving method is provided to improve link usage rates by improving fairness between TCP(Transmission Control Protocol) flows in a single domain and a multi-domain environment. CONSTITUTION: The yield fairness of an individual flow is improved in an integrated traffic management method in a differentiated service for a network in a ship. A TCP user uses AS(Assured Service) without managing user flows. The yield and the link usage rate are improved in a minimum bandwidth, a surplus bandwidth, and bandwidth shortage. The improvement of the yield fairness and the link use rate is confirmed in the improved single domain environment and the multi-domain environment.
Abstract:
PURPOSE: A cooperative transmission method strong against frequency selective fading is provided to obtain a cooperative diversity gain through asynchronous cooperative communication in a frequency selective fading channel. CONSTITUTION: A source node(S) transmits a generated OFDM(Orthogonal Frequency Division Multiplexing) transmission symbol to relay nodes(R1,R2) respectively. Each relay node performs an amplification operation to the received symbol. A destination node(D) performs a cyclic prefix removal to the symbol received through each of the relay nodes. The destination node obtains an estimation value of combination symbols transmitted from the source node. The destination node demodulates actual data symbols through a recombination process by using the estimation value of the combination symbols.
Abstract:
PURPOSE: A space time coding OFDM(Orthogonal Frequency Division Multiplexing) based low complexity multiple antenna relay transmitting method is provided to increase diversity gain by using a relay mode, an antenna selection mode, or a circulation delay diversity mode. CONSTITUTION: A signal transmitted to a first timeslot from a source node(100) is received by a multiple receiving antenna. An amplification gain is determined in consideration of average transmission power of each receiving signal. An LC-STBC(Linear Combining-Space-Time Block Coding) signal processing of each receiving signal is performed. The processed signal is amplified as the amplifying gain. The amplified signal is transmitted to a target node(300) through multiple transmission antenna. [Reference numerals] (100) Source node; (300) Target node
Abstract:
H.264에서 MPEP-2로의 트랜스코딩 방법이 개시된다. 이 H.264에서 MPEP-2로의 트랜스코딩 방법은 선박-육지 간 실시간 통신에서 다양한 콘텐츠를 제공하는 방송국 및 콘텐츠 제공자는 위성 통신을 통하여 H.264 표준으로 압축한 동영상을 실시간으로 MPEG-2표준 디바이스를 사용 중인 선박에 원활한 서비스를 제공할 수 있게 된다.
Abstract:
본 발명은 군집선박을 위한 선박 USN을 이용한 상황인식 모니터링시스템에 관한 것으로서, 본 발명에 따른 선박 USN을 이용한 상황인식 모니터링시스템은 선박에 설치된 적어도 하나의 센서 중 지정된 선박의 역할에 따라 필요한 센서만을 동작시키고, 센서에 의해 수집된 데이터를 근거로 선박의 운항 또는 작업에 필요한 상황을 인식하며, 인식된 결과를 다른 선박에 전송하여 정보를 공유하는 것을 특징으로 한다.
Abstract:
본 발명은 주파수 관리 장치 및 방법에 대하여 개시한다. 본 발명의 일면에 따른 주파수 관리 시스템은, 각 네트워크의 서비스 클래스별 트래픽 부하와 시간별 트래픽 부하를 측정하며, 상기 각 네트워크의 통신 프로토콜을 결정하는 부하 측정기; 상기 결정된 통신 프로토콜의 트래픽 부하들을 고려할 때 상기 결정된 프로토콜로 통신시 필요한 대역폭을 산출하는 복수의 네트워크 운영자; 및 상기 트래픽 부하들을 고려하여 상기 각 네트워크 운영자의 우선순위를 부여하고, 상기 우선순위를 고려하여 전체 주파수 대역을 상기 각 네트워크 운영자에게 분할하여 할당하는 주파수 관리자를 포함하는 것을 특징으로 한다. 협업 통신, 주파수 관리자, 스펙트럼 매니저, 해상통신, FSA
Abstract:
본 발명은 선박 등의 이동체에 적용할 수 있는 태양 추적 방법에 관한 것으로, 보다 구체적으로는 태양광 발전 시스템을 전기 발전량에 따른 최적의 고도각 및 방위각을 가지도록 구동시키기 위한 태양 추적 방법으로서, 소정의 단위 별로 방위각 및 고도각이 변하도록 태양광 발전 시스템을 구동시켜 각각의 방위각 및 고도각에 따른 전기 발생량을 측정하고, 최대 전기 발생량이 측정된 위치로 태양광 발전 시스템을 구동시키는 과정을 주기에 따라 반복함으로써 전기 발생량을 최대화 시키는 방법을 제공한다. 선박, 태양광 발전, 태양 추적, 방위각, 고도각
Abstract:
PURPOSE: A wireless indoor location measuring method based on KNN(k-nearest Neighbor) and PCM(Possibilistic C-Mean) is provided to form a wireless fingerprint type database by measuring a signal to noise ratio from several APs. CONSTITUTION: The first electric wave feature data is stored in a database with a wireless fingerprint type(S110). k reference points are selected by using KNN(S120). A group of the first electric wave feature data of the k reference points is formed(S130). A group of a location coordinate of the k reference points is formed(S140). A group including the reference points included in the first electric wave feature data based group and the reference point location coordinate based group is formed(S150). A group with the minimum distance square value of a group central vector and the first electric wave feature data is selected(S160). The average of the location coordinate of the reference points belonging to the selected group is produced. The location of a terminal is estimated(S170).