Abstract:
PURPOSE: An adaptive playing device for scalable satellite broadcasting and a method thereof are provided to make the balance of computation complexity for a base layer stream and an enhancement layer stream by selectively performing operation modules of two decoding units. CONSTITUTION: A firsts decoding unit(230) and a second decoding unit(240) are successively processed for decoding a first video stream, a second video stream, and an audio stream. The first decoding unit and the second decoding unit comprise a plurality of operation modules which are individually controllable. The first decoding unit and the second decoding unit are operated in parallel. A control unit(250) selectively operates each of the operation module.
Abstract:
PURPOSE: An apparatus and method for transmitting data in a terminal of a satellite communication system are provided to enhance the efficiency of a transmitter of high power consumption in satellite communication. CONSTITUTION: A baseband signal processing unit(200) modulates data signals into IF(Intermediate Frequency) signals. After amplifying a synthesized signal, the baseband signal processing unit extracts only predetermined band. A transmission signal processing unit(230) extracts phase content and amplification content from the extracted signal. After amplifying divided amplitude content and amplitude-limited phase content, the transmission signal processing unit outputs the synthesized signal as the band signal for satellite transmission.
Abstract:
PURPOSE: A phase locked loop and a satellite communication terminal using the same are provided to obtain low satellite noise characteristics in high and low frequency bands by reducing the phase noises of a satellite synchronization loop. CONSTITUTION: A voltage control oscillator(407) outputs a frequency variable depending on an output terminal, and a frequency down converter(409) down-converts the frequency outputted from a voltage control oscillator according to the frequency band outputted form voltage control oscillator. A frequency divider(411) divides the frequency down-converted in the frequency down-converting unit.
Abstract:
PURPOSE: A method and an apparatus for transmitting/receiving data by using a satellite channel are provided to use low cost analog device in a terminal by providing excellent transmission performance under a weak communication environment. CONSTITUTION: When receiving bit data, the encoding unit performs channel encoding through an e-BCH(extend BCH) code. An interleaver(103) interleaves the encoded data through the encoding unit. A modulation unit(105) modulates interleaved data through a CPM(Continuous Phase Modulation) method which use 4 symbols, and a transmission unit(107) transmits the modulated data to a primary center.
Abstract:
본 발명은 디지털 변조신호의 비트 매핑 장치 및 그 방법에 관한 것으로, 디지털 변조 방식의 성상도(constellation) 상에서 내부 링과 외부 링의 형태를 가지는 각 심벌에 정보 비트 매핑 시, 외부 링 내 정보 비트들을 반시계 방향으로 하나씩 쉬프트(shift)시켜 매핑함으로써, 송수신 증폭기에서 발생하는 비선형 채널 특성을 극복하여 비트 오류율을 감소시키기 위한, 디지털 변조신호의 비트 매핑 장치 및 그 방법을 제공하고자 한다. 이를 위하여, 본 발명은 디지털 변조신호의 비트 매핑 방법에 있어서, 내부 링과 외부 링의 형태를 가지는 성상도(constellation) 상에 각 비트들을 매핑하는 초기 매핑 단계; 및 상기 외부 링 내 비트들을 쉬프트(shift)시켜 비트를 최종 매핑하는 최종 매핑 단계를 포함한다. 4+12 APSK, 성상도, 비트 매핑, 쉬프트, 비선형 특성
Abstract:
PURPOSE: A moving satellite transmission and reception apparatus and a communication route are provided to control a communication route for receiving a satellite signal received from different communication route without a disconnection phenomenon of a data. CONSTITUTION: A first antenna device(111) receives a signal through a first communications route. A second antenna device(112) receives the signal through a second communications route. A data processor(101) compares a cyclic redundancy check value about a packet stream of the signal received respectively the second antenna device and the first antenna device to the per packet. The data processor changes one communication route among the first communication route and the second communication route when the packet in which the CRC value is same is detected.
Abstract:
PURPOSE: A correlation apparatus for the strong synchronous acquisition and method uses the distance value about the receiving symbol. The frequency error can be over gotten. CONSTITUTION: The receiving symbol phase difference calculation unit(201) obtains the receiving symbol phase difference between the delay receiving symbol delaying the receiving symbol and the receiving symbol. The correlation symbol phase difference calculation unit(203) obtains the correlation symbol phase difference between the lag correlation symbol delaying the correlation symbol and the correlation symbol. The gradation correlator(205) uses the receiving symbol phase difference and correlation symbol phase difference.
Abstract:
PURPOSE: An apparatus and a method for performing handover between different networks using location information and a mobile router are provided to supply an internet service in which a session is not disconnected to a fixed node. CONSTITUTION: A handover starting information storage unit(320) stores handover execution location information. A handover execution determining unit(330) determines whether a mobile router needs handover execution into a network of a different type from a connection network based on information stored in the handover starting information storage unit according to current location information grasped in the location information grasping unit. A handover performing unit(340) performs handover according to the determination result.
Abstract:
PURPOSE: An apparatus and a method for transmitting variable length packet data and a device for receiving data are provided to transmit synchronization information in a satellite communication network environment to which a variable length packet transmission method is applied. CONSTITUTION: A data transmitter(10) inserts synchronization information to transmission data to be transmitted according to a variable length packet transmission method. The data transmitter transmits the transmission data into which the synchronization information is inserted to a data receiver. The data receiver(20) receives the transmission data including synchronization information from the data transmitter. The data receiver restores synchronization data included in the received transmission data. The data receiver synchronizes with the data transmitter according to the restored synchronization data.