Abstract: Disclosed are an apparatus and a method for decreasing a channel change time in a digital broadcasting reception terminal. Starting time information of at least one non-reference channel is selected. When the user selects a non-reference channel, broadcast data thereof is received by using the collected starting time information. The apparatus extracts time offset values between a starting time of a current reference channel and that of each at least one non-reference channel, and then obtains the starting time of each non-reference channel by using the extracted time offset values. When a channel change is performed, the starting time of the non-reference channel is established to receive broadcast data based on the starting time according to a corresponding time offset value. Hence, a time period required for a channel change is significantly reduced.

Abstract: A gap filler apparatus providing cyclic delay diversity in a digital multimedia broadcasting (DMB) system. In the gap filler apparatus, a receiver receives an orthogonal frequency division multiplexing (OFDM) signal transmitted as a broadcasting signal. A symbol synchronization unit acquires symbol synchronization of the OFDM signal, detects a guard interval of an OFDM symbol using the symbol synchronization, determines a sample length, by which the OFDM symbol is cyclic-delayed within the guard interval, and cyclic-delays the OFDM signal by the determined sample length. An amplifier amplifies the cyclic-delayed OFDM signal. A transmitter transmits the amplified OFDM signal to a wireless network.

Abstract: Provided are an apparatus and a method for creating a widget of a portable terminal. The method includes: determining a building block that a user selects on a widget creating screen including building blocks necessary for widget creation; generating a tag of data corresponding to the confirmed building block; and generating a widget code including the building block and the tag.

Abstract: A method and apparatus for performing channel compensation and symbol demodulation using an estimated channel impulse response during coherent demodulation of a received Orthogonal Frequency Division Multiplexing (OFDM) signal are provided. In the apparatus, an FFT processor IFFT-processes a received signal. A channel compensator generates a channel-compensated signal by multiplying the FFT received signal by an estimated channel impulse response and calculates the power of the estimated channel impulse response. A symbol demodulator sets the power of the estimated channel impulse response as a reference point defining a minimum distance between signal points in a signal constellation, and decides soft metric values for channel decoding using the reference point and I-channel and Q-channel signal components of the channel-compensated signal. A decoder recovers information bits by decoding the soft metric values.

Abstract: An optimum I/Q imbalance compensating apparatus and method in a zero-IF OFDM receiver. In the apparatus, a first compensator generates a first symbol by removing interference from a second distorted symbol on an (Ns?m+1)th subcarrier from a first distorted symbol on an mth subcarrier by a first compensation coefficient in an OFDM FFT signal of Ns subcarriers. A first hard decider generates a first compensated symbol by hard-decision on the first symbol, an error calculator generates an error symbol by subtracting the first received symbol from the first compensated symbol. A second compensator generates a second symbol by eliminating interference from the first distorted symbol from the second distorted symbol using a second compensation coefficient. A second hard decider generates a second compensated symbol by hard-decision on the second symbol, and an adaptive controller updates the first compensation coefficient using the error symbol and the second compensation symbol.

Abstract: An apparatus and method for receiving control information transmitted from a transmitter using one of a plurality of slot lengths in a high-speed packet transmission mobile communication system is provided. The apparatus and method includes a decoder adapted to receive symbols by the slot, and generate at least one bit stream by decoding as many symbols of at least one possible slot length among a plurality of slot lengths according to a previous decoding result. An error checker adapted to perform error checking on the bit stream from the decoder. A controller is adapted to provide symbols of one more consecutive slot to the decoder, if the error checking failed, and acquire control information from the error checking-passed bit stream, if the error check passed. The decoder is further adapted to output at least one frame quality metric for the bit stream along with the bit stream.

Abstract: An apparatus and method for measuring an SIR in a CDMA mobile communication system. The SIRs and power of PICHs and the power of PDCHs are measured sequentially for a plurality of active set base stations. An active set base station having the highest signal strength is selected according to the measurements. Thus a data rate is determined adaptively to the SIR for efficient high rate packet data transmission.

Abstract: An apparatus for removing a DC offset during frequency direct conversion in a reception device of a wireless communication system. In the apparatus, an adder receives a digital baseband signal comprising a DC component, receives an estimated DC offset value, and calculates a difference between the digital baseband signal with the DC component and the estimated DC offset value. A DC offset calculator receives gain mode information of an analog element of the reception device, and calculates the estimated DC offset value according to the gain mode.

Abstract: Disclosed is a method for a handover of a digital broadcasting reception terminal employing a time division multiplexing scheme, which periodically receives broadcast data through each of one or more broadcasting channels provided in a predetermined frequency band, the method including the steps of: when broadcast data of a channel selected by a user in a current cell is received, detecting handover determination information from the received broadcast data; determining if it is necessary to perform a handover to an adjacent cell by using the handover determination information; searching channels provided by the cell to which the terminal will be handed over for a channel providing broadcast data equal to that provided by the selected channel, when it is determined that it is necessary to perform a handover; and when a channel providing broadcast data equal to that of the selected channel is found, performing a handover to a corresponding cell and receiving broadcast data of the found channel.

Abstract: Provided is a method and apparatus for decoding a Multi-Protocol Encapsulation Forward Error Correction (MPE-FEC) frame in a Digital Video Broadcasting-Handheld (DVB-H) system. Packet Identifier (PID) filtering is performed on a Transport Stream (TS) packet received via a wireless network to detect a TS packet, and a table ID is detected from header information of the section data to identify the section data type. If the section data is an MPE section, frame buffering is performed. If there is a remaining portion in the data region after storage of an IP datagram of the last MPE section, zero-padding is performed on the remaining portion. If the section data is an MPE-FEC section, frame buffering is performed on parity data extracted from the MPE-FEC section.

Abstract: Disclosed are an apparatus and a method for decreasing a channel change time in a digital broadcasting reception terminal. Starting time information of at least one non-reference channel is selected. When the user selects a non-reference channel, broadcast data thereof is received by using the collected starting time information. The apparatus extracts time offset values between a starting time of a current reference channel and that of each at least one non-reference channel, and then obtains the starting time of each non-reference channel by using the extracted time offset values. When a channel change is performed, the starting time of the non-reference channel is established to receive broadcast data based on the starting time according to a corresponding time offset value. Hence, a time period required for a channel change is significantly reduced.

Abstract: An apparatus and method are provided for receiving data generated by sequentially performing bit interleaving, symbol interleaving and symbol mapping in a wireless communication system. A fast Fourier transform (FFT) processor receives in-phase/quadrature phase (I/Q) data of a radio channel generated by sequentially performing bit interleaving, symbol interleaving and symbol mapping, and performs an FFT process for the I/Q data. A symbol deinterleaver performs a process for symbol deinterleaving the FFT I/Q data and reference values to be used for symbol demapping of the I/Q data and outputs the symbol-deinterleaved I/Q data and reference values. A symbol demapper performs a process for symbol demapping the symbol-deinterleaved I/Q data according to the reference values. A bit deinterleaver performs a process for bit deinterleaving the symbol-demapped data. A demultiplexer demultiplexes the bit-deinterleaved data.

Abstract: A method and apparatus of multi-Cyclic Redundancy Checking (CRC) are provided for section detection and reliability information acquisition in a Digital Video Broadcasting-Handheld (DVB-H) system. A Packet Identifier (PID) filtering process is performed for a packet received through a radio network. A transport stream packet including section data is detected. A CRC process is performed for a payload of an associated section using header information of the section data and frame buffering is processed. The method and apparatus can perform CRC in a parallel fashion using multiple CRC checkers without interference between adjacent sections and can perform section detection and reliability verification.

Abstract: A method and apparatus for synchronization of a moving picture experts group (MPEG) transport stream, which minimizes an initial delay are provided. A packet synchronization unit and a mode of the packet synchronization unit to are initialized to “0”. Values of sync words are stored by shifting values of a sync word register when the sync words have been received and the received sync word is compared with predetermined code words As a result of the comparison, a determination is made as to whether a bit difference between the sync words and the predetermined code words exceeds a predetermined threshold value.

Abstract: An apparatus for detecting a frame transmission period in a CDMA mobile communication system supporting a discontinuous transmission mode. A first frame detector performs primary frame detection by calculating a signal-to-interference ratio (SIR) using traffic symbol energy, pilot symbol energy and noise energy measured for a predetermined time period, and comparing the SIR with a predetermined frame detection threshold value. A decoder calculates a symbol error rate (SER) by decoding symbols received for the predetermined time period. A second frame detector selects an SER threshold value according to frame detection information from the first frame detector, and compares the selected SER threshold value with the SER to determine whether a frame has been transmitted.

Abstract: A method and apparatus for performing channel compensation and symbol demodulation using an estimated channel impulse response during coherent demodulation of a received Orthogonal Frequency Division Multiplexing (OFDM) signal are provided. In the apparatus, an FFT processor IFFT-processes a received signal. A channel compensator generates a channel-compensated signal by multiplying the FFT received signal by an estimated channel impulse response and calculates the power of the estimated channel impulse response. A symbol demodulator sets the power of the estimated channel impulse response as a reference point defining a minimum distance between signal points in a signal constellation, and decides soft metric values for channel decoding using the reference point and I-channel and Q-channel signal components of the channel-compensated signal. A decoder recovers information bits by decoding the soft metric values.

Abstract: An optimum I/Q imbalance compensating apparatus and method in a zero-IF OFDM receiver. In the apparatus, a first compensator generates a first symbol by removing interference from a second distorted symbol on an (Ns?m+1)th subcarrier from a first distorted symbol on an mth subcarrier by a first compensation coefficient in an OFDM FFT signal of Ns subcarriers. A first hard decider generates a first compensated symbol by hard-decision on the first symbol, an error calculator generates an error symbol by subtracting the first received symbol from the first compensated symbol. A second compensator generates a second symbol by eliminating interference from the first distorted symbol from the second distorted symbol using a second compensation coefficient. A second hard decider generates a second compensated symbol by hard-decision on the second symbol, and an adaptive controller updates the first compensation coefficient using the error symbol and the second compensation symbol.

Abstract: A gap filler apparatus providing cyclic delay diversity in a digital multimedia broadcasting (DMB) system. In the gap filler apparatus, a receiver receives an orthogonal frequency division multiplexing (OFDM) signal transmitted as a broadcasting signal. A symbol synchronization unit acquires symbol synchronization of the OFDM signal, detects a guard interval of an OFDM symbol using the symbol synchronization, determines a sample length, by which the OFDM symbol is cyclic-delayed within the guard interval, and cyclic-delays the OFDM signal by the determined sample length. An amplifier amplifies the cyclic-delayed OFDM signal. A transmitter transmits the amplified OFDM signal to a wireless network.