Abstract:
위성네트워크및 유선네트워크를포함하는다중전송경로환경에서데이터를송수신하는장치가제공된다. 위성네트워크경로를통해콘텐츠데이터를수신하고, 유선네트워크경로를통해콘텐츠데이터를복원하기위한정보를포함하는리던던트데이터를수신하며, 수신된콘텐츠데이터의손실데이터를리던던트데이터를이용하여복구할수 있다. 이때리던던트데이터는네트워크코딩을적용하여생성된것일수 있다.
Abstract:
Provided is a system and a method for satellite communication which receives a channel state information of a forward link connected to a subscriber terminal station; resets a modulation and coding (MODCOD) of a physical layer based on the received channel state information; and changes a congested window value of a transmission layer according to the reset MODCOD value of the physical layer.
Abstract:
PURPOSE: A transmission control protocol (TCP) packet loss classifying device and a method thereof are provided to classify the packet loss and the network congestion by using the wireless channel status information which is received from the transmission TCP, thereby improving the TCP performance by avoiding unnecessary congestion control. CONSTITUTION: A receiving unit (210) receives more than one TCP data packet from a TCP transmission terminal. A measuring unit (220), when receiving the TCP data packet, measures the quality value of current channel and periodically updates to the TCP layer. A status measuring unit (230) measures the wireless channel status information which is estimated by relating the TCP layer to the physical layer. A transmission unit (240) transmits the wireless channel status information to the TCP transmission terminal by including to the ACK packet. The transmission unit transmits more than one TCP data packet to the TCP transmission terminal. [Reference numerals] (210) Receiving unit; (220) Measuring unit; (230) Status estimation unit; (240) Transmission unit; (AA) TCP receiving terminal
Abstract:
위성통신시스템에서역방향링크패킷오류검출방법이개시된다. 역방향링크를통해패킷을수신하는위성통신장치에서수행되는역방향링크의패킷오류검출방법은, 역방향링크를통해수신된적어도하나의분할된패킷을조합하여제1 역방향링크패킷조합을생성하는단계및 제1 역방향링크패킷조합이생성된후에수신된적어도하나의제2 역방향링크패킷의분할정보와, 제1 역방향링크패킷조합의조합완성여부및 패킷처리상태정보중 적어도하나의정보를이용하여패킷의오류를판단하는단계를포함한다. 따라서, 수신된패킷의재조립오류로인한패킷손실을최소화할수 있다.
Abstract:
Provided are an apparatus and a method for controlling a satellite terminal by which a packet loss rate of a return link is measured by a central station, an modulation and coding (MODCOD) of the return link is determined by using the packet loss rate, and an MODCOD of a satellite terminal apparatus for the return link is controlled. [Reference numerals] (110) Packet loss rate measuring unit; (120) MODCOD determining unit; (130) MODCOD control unit
Abstract:
PURPOSE: A method for detecting return link packet errors in a hub in communication with a satellite terminal and an apparatus thereof are provided to reduce the loss of packets while the satellite terminal transmits the packets to a return link. CONSTITUTION: A transmitting part(730) transmits a normal link packet to a satellite terminal. A receiving part(710) receives return link packets from the satellite terminal. An error verifying part(750) successively combines the return link packets to generate a first return link packet. The errors of the packets are verified by comparing/analyzing the first return link packet and a subsequently received second return link packet according to the data length of the first return link packet.
Abstract:
PURPOSE: A channel prediction method based on weather data and a device thereof are provided to select an optimal encoding and decoding method by accurately predicting a channel state by using the weather data. CONSTITUTION: A filtering unit(112) extracts channel predicting information from a message including channel measurement information received from a terminal. The filtering unit acquires sample data by processing the channel estimation information. A weather data acquisition unit(113) acquires weather data corresponding to a location where the terminal is located. A channel prediction unit(115) calculates a channel prediction value based on the sample data and the weather data. A determination unit(116) determines an encoding method and a decoding method for processing data based on the channel prediction value. [Reference numerals] (11) Channel prediction device; (111) Message authentication unit; (112) Filtering unit; (113) Weather data acquisition unit; (114) Data storage unit; (115) Channel prediction unit; (116) Determination unit