Abstract:
위성 및 위성의 지상보조장치를 이용한 이동위성서비스의 주파수 공유 장치 및 방법을 개시한다. 위성 및 위성의 지상보조장치를 이용한 이동위성서비스의 주파수 공유 방법은 위성으로부터 수신한 신호의 세기를 측정하는 단계와, 측정된 신호의 세기에 따라, 통신 모드를 결정하는 단계와, 통신 모드에 따라, 위성 또는 위성의 지상보조장치 중 어느 하나의 장치와 통신하는 단계를 포함한다. 위성, 지상보조장치, 주파수, 공유
Abstract:
PURPOSE: A signal processing method in a relay apparatus is provided to increase spectrum efficiency by utilizing high dimensional modulation method. CONSTITUTION: An external apparatus transmits a signal modulated by a low-dimensional modulation symbol including basic information bit to a repeater(200). The repeater transmits a signal modulated by a high-dimensional modulation symbol including an additional information bit and the restored basic information bit to the terminal(210). The terminal restores the information bit by selecting or combining the signal of the repeater and the signal of the external apparatus(220).
Abstract:
PURPOSE: A communication method using symbol interleaving and an apparatus thereof are provided to reduce a data transmission error when AMC(Adaptive Modulation and Coding) is used in an LTE(Long Term Evolution) base satellite communication system. CONSTITUTION: An information exchange unit(110) receives memory information and service information from a terminal device(200). An interleaver use determination unit(120) determines the active condition of an interleaver based on the service information. An interleaver information determination unit(130) determines interleaver information based on resource allocation type information and the memory information. An encoding unit(140) modulates and encodes data. A symbol interleaver(150) interleaves data, which is encoded by using the interleaver information, by symbol. A data transmission unit(160) transmits the data interleaved by the symbol to a terminal.
Abstract:
PURPOSE: A resonator filter and a diplexer which includes a triple mode resonator and dual mode resonator are provided to alternatively use the triple mode resonator and dual mode resonator with the similar shape as the triple mode resonator, thereby controlling frequencies of each resonance mode. CONSTITUTION: A first dual mode resonator(110) comprises independent control parts which control each frequency according to two resonance modes. A triple mode resonator(130) comprises independent control parts which control each frequency according to three resonance modes which are different from the two resonance modes. A first combining part(120) electrically and mutually combines the first dual mode resonator and triple mode resonator. A second dual mode resonator(140) comprises independent controlling parts which control each frequency according to two resonance modes which are different from the three resonance modes and two resonance modes. A second combining part(150) electrically and mutually combines the triple mode resonator and second dual mode resonator.
Abstract:
PURPOSE: A service providing system in a satellite communication system by allocating resources and power to hierarchical antenna multi beams, and a method thereof are provided to improve the efficiency in the use of power by reducing the power consumption of a system. CONSTITUTION: A service providing system in a satellite communication system includes a satellite(102), a first terminal(170), a gateway(104), a core network(106), an access network(110), a BS(Base Station)(108), a CGC(Complementary Ground Component)(132), and a plurality of terminals. The satellite is a satellite BS configured to provide a communication service by using hierarchical multi-beams. The first terminal is located in a suburb to receive the communication service from the satellite. The gateway is configured to connect signal transmission and reception between the satellite and a terrestrial system. The core network is included in the terrestrial system and configured to transmit and receive signals to and from the satellite through the gateway. The gateway is a centralized gateway or one gateway of geographically distributed gateways, depending on the satellite communication system or requirements from an operator of the satellite communication system. The gateway is connected to the BS as a sub system which is connected to the core network or the access network. In the satellite communication system, the satellite forms the hierarchical multi-beams through an MIMO(Multi-Input Multi-Output) scheme in which one satellite uses a polarization characteristic of an antenna, or a plurality of satellites form the hierarchical multi-beams and transmit a signal to provide a communication service. Accordingly, the data transmission capacity may be increased, and the data reception function may be improved.
Abstract:
PURPOSE: A hierarchical random access method for a wireless communication system having very large cell area are provided to design slot length to integral times of basic slot length according to timing error compensation capability, thereby enabling terminals to user various slot lengths. CONSTITUTION: Terminals not having a timing compensation capability uses the first slot(110). According to timing compensation capability, terminals without timing compensation capability uses two more slots(120,130). According to capability of terminals, many RACH slots are assigned to terminals. Therefore, the terminals has much more random access chances at the same time. In hierarchical RACH structure, whole preamble sequence(111) assigned to RACH is assigned according to a layer.
Abstract:
A method for removing an inter-carrier interference in a mobile communication system is provided to remove an inter-carrier interference by reducing a frequency offset according to a channel state. A transmitting part generates a control signal(S101). The transmitting part transmits a control signal through a wireless channel(S103). A receiving part checks a generating state of a frequency offset of the received control signal(S105). The receiving part estimates a channel state and a SNR(Signal to Noise Ratio)(S107). The receiving part generates feedback information including a channel quality indicator corresponding to the estimated channel state and the SNR(S109). The receiving part transmits the feedback information to the transmitting part through a wireless channel(S111). The transmitting part predicts a channel state about the wireless channel(S113). The transmitting part generates an OFDM(Orthogonal Frequency Division Multiplexing) signal(S115). The transmitting part transmits the OFDM signal to the receiving part(S117). The transmitting part determines an excessive state of a coherence time(S119). The transmitting part checks an additional transmission(S121).
Abstract:
An electric wave resource re-using system and a method thereof are provided to secure the electric wave resource required for transmitting repeater data to a user terminal. A signal receiver(410) restores a signal received from an LM1 link or Lp link. A repeater data manager(430) manages data received from a satellite or base station and repeater data. A signal transmitter(440) transmits a signal of the repeater data manager to a user terminal of the second communication area through the electronic wave resource determined by an electronic wave resource reusing unit(420). The electronic wave resource reusing unit determines a portion of the whole electric wave resource of a system which can be re-used in a repeater.