| Patent application number | Description | Published |
|---|
| 20090154458 | REPETITION APPARATUS AND METHOD FOR REPEATEDLY TRANSMITTING AND RECEIVING DATA PACKET USING DIFFERENT PUNCTURING PATTERNS - Provided are repetition apparatus and method for repeatedly transmitting and receiving a data packet using different puncturing patterns to overcome signal attenuation and fading in a high speed mobile environment by repeatedly transmitting the duplicated information bit sequences with parity bits having a different puncturing pattern after channel-encoding the duplicated information bit. The repetition apparatus for repeatedly transmitting a data packet, includes a dual data generator for generating duplicated information bit sequences identical to each of information bit sequences to transmit, a channel encoder for dividing each of the duplicated information bit sequences into a plurality of information bits, and generating coded data packets alternately having a plurality of parity bits according to different puncturing patterns for each of the divided information bits, and a transmitter for transmitting the generated coded data packets sequentially. | 06-18-2009 |
| 20100046415 | METHOD AND SYSTEM FOR EFFECTIVE ADAPTIVE CODING AND MODULATION IN SATELLITE COMMUNICATION SYSTEM - A Second Generation Digital Video Broadcasting via Satellite (DVB-S2) system is provided. More particularly, a method and apparatus for maintaining synchronization of a signal by changing an Adaptive Coding and Modulation (ACM) method that is used for a conventional DVB-S2 system are provided. In the apparatus and method, an FEC frame of a variable length is formed by turbo encoding rather than Bose-Chaudhuri-Hocquenghem (BCH) and Low Density Parity Check (LDPC) encoding, and a Physical Layer (PL) frame of a specific length is formed regardless of a modulation method, so that a satellite terminal receives a signal transmitted at a specific length regardless of a modulation method or a coding rate to easily maintain synchronization without interruption and efficiently transmit the signal. | 02-25-2010 |
| 20100135198 | APPARATUS FOR MOBILE SATELLITE COMMUNICATIONS AND METHOD OF CONTROLLING COMMUNICATIONS ROUTE - A mobile satellite transmission/reception apparatus and a communications route control method using the same are disclosed. The mobile satellite transmission/reception apparatus comprises: a first antenna unit configured to receive a signal along a first communications route; a second antenna unit configured to receive a signal along a second communications route; and a data processor configured to compare cyclic redundancy check (CRC) values with respect to packet streams of signals respectively received by the first and second antenna units, and change communications route to one of the first and second communications routes if packets having the same CRC value are detected. | 06-03-2010 |
| 20100135327 | APPARATUS AND METHOD FOR GENERATING FRAME FOR MPE-FEC DECODING - An apparatus and method for generating frames for MPE-FEC decoding are disclosed. The apparatus for generating frames for MPE-FEC decoding includes: a packet reception unit configured to receive a packet; a packet attribute inspection unit configured to inspect whether or not the received packet forms a header part of a section; and a frame generation unit configured to generate a frame according to different methods depending on whether or not the packet forms a header part of a section. | 06-03-2010 |
| 20100138726 | MPE-FEC RS DECODER AND DECODING METHOD THEREOF - A decoding method of an MPE-FEC (MultiProtocol Encapsulation-Forward Error Correction) RS (Reed-Solomon) decoder, includes: substituting a value corresponding to an erasure error position with 0 in a reception signal; calculating a syndrome by using the reception signal; calculating an erasure position polynomial by using erasure information; calculating a modified syndrome by using the syndrome and the erasure position polynomial; calculating an erasure error size polynomial by using the modified syndrome; calculating an error position by using the erasure position polynomial; calculating an error size by using a modified Formey's algorithm; and correcting an error through the error position and the error size. | 06-03-2010 |
| 20100138878 | RECEIVER CIRCUIT OF SATELLITE DIGITAL VIDEO BROADCAST SYSTEM - A receiver circuit of a satellite digital video broadcast system includes: a multiplication unit outputting a synchronized reception symbol by multiplying a reception symbol by frequency error information as a feedback; a common autocorrelation unit acquiring autocorrelation values for each symbol by multiplying the synchronized reception symbol by an autocorrelation coefficient; a frame synchronization unit detecting a SOF (Start Of Frame), which is a synchronization word indicating start of a frame, from the autocorrelation values for each symbol; a frequency synchronization unit estimating the frequency error information based on the autocorrelation values for each reception symbol and the SOF; and an SNR estimation unit estimating an SNR (Signal to Noise Ratio) based on the autocorrelation values for each symbol and the SOF. | 06-03-2010 |
| 20100142625 | METHOD FOR GENERATING AND PROCESSING HIERARCHICAL PES PACKET FOR DIGITAL SATELLITE BROADCASTING BASED ON SVC VIDEO - A method for generating and processing a hierarchical packetized elementary stream (PES) packet for digital satellite broadcasting based on SVC (Scalable Video Coding) video is disclosed. That is, when SVC video is applied to a digital satellite broadcasting system, a transmitter side can generate a hierarchical PES packet in consideration of a hierarchical structure of SVC video and a receiver side can effectively process a received hierarchical PES packet. | 06-10-2010 |
| 20100158091 | FREQUENCY ERROR ESTIMATOR AND FREQUENCY ERROR ESTIMATING METHOD THEREOF - Provided is a frequency error estimating method of a communication system. The method includes receiving a frame, and calculating a frequency error from a SOF field of the received frame. | 06-24-2010 |
| 20110006950 | MICROSTRIP ANTENNA COMPRISED OF TWO SLOTS - Disclosed relates to a microstrip antenna, particularly, relates to a dual band microstrip antenna including two slots. The microstrip antenna includes a conductor plate having a first hole and a substrate having a microstrip patch where slots of two different sizes are positioned, the substrate being located on a top of the conductor plate. | 01-13-2011 |
| 20110047199 | CORRELATION APPARATUS AND METHOD FOR ACQUIRING ROBUST SYNCHRONIZATION - Provided is a correlation apparatus and method for acquiring a robust synchronization. The correlation method may include: calculating a received symbol phase difference with respect to a received symbol; calculating a correlation SoF symbol phase difference with respect to a correlation SoF symbol for a correlation; calculating a differential correlation value of the received symbol using the received symbol phase difference and the correlation SoF symbol phase difference; calculating a Euclidean distance value of the received symbol using the received symbol phase difference; and calculating a sum correlation value of the received symbol using the differential correlation value and the Euclidean distance value. | 02-24-2011 |
| 20110113302 | TERMINAL TRANSMISSION APPARATUS FOR PROVIDING MULTIMEDIA SERVICE VIA SATELLITE COMMUNICATION LINK AND METHOD FOR PROVIDING MULTIMEDIA SERVICE USING THE SAME - The present invention separates inputted triple play IP data into Internet and TV data and voice (VoIP) data, encodes the Internet and TV data permitting a long delay time according to the existing DVB-S2 standard, and encodes the voice data permitting only a short delay time according to a DVB-RCS+M standard based 4K mode. Each encoded data is subjected to the orthogonal modulation and the orthogonally modulated voice data is subjected to a direct sequence spectrum spread according to a spreading factor. The spread spectrum signal is multiplexed in a SCPC frequency division multiple access (FDMA) scheme so as to overlap with frequencies allocated to each user. | 05-12-2011 |
| 20110131615 | SOURCE-CHANNEL COMBINED CODING METHOD AND SATELLITE BROADCASTING SYSTEM USING THE SAME - A source-channel combined coding method including: determining whether a channel signal-to-noise ratio (SNR) is varied or not; when it is determined that the channel SNR is varied, selecting a MODCOD suitable for the channel SNR by referring to a first table defining an SNR threshold value at which data transmission is performed without an error, for each MODCOD designating a low density parity check (LDPC) code rate and a modulation scheme; calculating a source coding rate by using an effective information bit rate of the selected MODCOD; extracting network abstraction layer (NAL) units for each layer from an inputted video frame so as to satisfy the calculated source coding rate, and packetizing the extracted NAL units; binding packets to configure a baseband (BB) frame; and LDPC coding and modulating the BB frame through the code rate and the modulation scheme which are designated by the selected MODCOD. | 06-02-2011 |
| 20110142005 | METHOD AND SYSTEM FOR FAST LAYER 3 HAND-OVER - The present invention relates to a method of seamlessly providing a satellite multimedia Internet service to a fixed subscriber belonging to a lower user network even in a satellite shadow environment and shortening a hand-over processing time between heterogeneous networks by applying a fast layer 3 hand-over technology between satellite and wireless networks in a mobile satellite terminal device. | 06-16-2011 |
| 20110149906 | METHOD FOR REDUCING PACKET ORDERING TIME OF LAYER 3 HANDOVER AND MOBILE SATELLITE TERMINAL USING THE SAME - There are provided a method for reducing a packet ordering time of layer 3 handover and a mobile satellite terminal using the same. The method for reducing a packet ordering time of layer 3 handover of a mobile router in a home agent of a satellite network connected with the mobile router includes: transmitting a first packet and a second packet to the mobile router through a satellite link of the mobile router; transmitting a sequence control packet to the mobile router through the satellite link; and transmitting a third packet to the mobile router via a wireless link of the mobile router. The sequence control packet provides a reference time for rapidly reordering the second and third packets which reach the mobile router in a reverse sequence. | 06-23-2011 |
| 20110150123 | TRANSMITTER, RECEIVER, TRANSMITTING METHOD, AND RECEIVING METHOD FOR COMMUNICATION SYSTEM - The present invention relates to a transmitting method, a receiving method, a transmitter, and a receiver of a communication system. A transmitting method according to an aspect of the present invention includes generating a burst by scattering a plurality of pilot symbols, and transmitting the burst. | 06-23-2011 |
| 20110150133 | BITS-TO-SYMBOL MAPPING METHOD FOR 4+12+16 APSK MODULATION - Disclosed is a bits-to-symbol mapping method of 4+12+16 amplitude phase shift keying (APSK) having excellent performance against the non-linearity of a high power amplifier. According to the present invention A bits-to-symbol mapping method of 4+12+16 APSK modulation, comprising: representing 32 symbols of the 4+12+16 APSK modulation by a polar coordinate and arranging the 32 symbols by a size of θ while giving priority to a symbol having a small signal size when the size of θ of two or more symbols are same; grouping the arranged 32 symbols into 4 groups according to quadrant regions where the symbols are located; and allocating bits so that the same bits are allocated to the symbols belonging to the same region for each region with respect to each of the first to fifth bits of the symbols grouped into four regions. | 06-23-2011 |
| 20110150143 | SOFT-DECISION DEMAPPING METHOD FOR DIGITAL SIGNAL - Disclosed is a demapping method of a soft-decision of an efficient soft determining scheme which is applicable to a DVB-2 satellite communication system. The soft-decision demapping method for a digital signal received through a transmission channel in a communication system using a phase shift keying (PSK) scheme includes: selecting reference symbols in an area having a higher probability than a predetermined probability that the received signal will be positioned among all reference symbols on a constellation diagram using a most significant bit (MSB) value of the received signal; and acquiring a maximum value of a log likelihood ratio (LLR) for the selected reference symbols. | 06-23-2011 |
| 20110151777 | DUAL MODE SATELLITE VERY SMALL APERTURE TERMINAL APPARATUS AND CONTROLLING METHOD THEREOF - Provided are a satellite VSAT apparatus and a control method thereof. The satellite VSAT apparatus according to an exemplary embodiment of the present invention can switch a modulation type of a signal to be transmitted from an indoor unit (IDU) to the outdoor unit to a linear or non-linear type in a case in which outputting of a transmitted signal is not controlled to an outdoor unit due to limitations, that is, there is no function such as an automatic signal level control in a block up-converter (BUC), a case in which transmission output limitation is large due to a lot of interference requirements for an adjacent channel, a case in which the number of adjacent channels (carriers) is large, or a case in which adjacent channel interference is large due to a frequency in a satellite multi-beam environment and polarization reuse, in a satellite VSAT apparatus system which aims at a low-priced user terminal. | 06-23-2011 |
