Samsung Electronics Co., Ltd.

Ji-Won Ha

Sang-Min Bae

Hyun-Seok Oh

Sung-Jin Park

Min-Goo Kim

Jong-Han Kim

Hyun-seok Yu

Jin-Woo Heo

Soo-Bok Yeo

Eun-Jeong Yim

Jong-Chul Park

Gin-Kyu Choi

Se-Hyoung Kim

Jae-Sun Park

Hee-Jin Roh

Jong-Han Lim

Soo-bok Yeo

Yong-Won Shin

Woo-Sang Hong

Jeong-Hoe Ku

Jung-Wook Yoon

Jin-Wook Han

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. A verification is then made as to whether all bits of the sync words correspond to all bits of the predetermined code words, when it is determined as a result of the determination that the bit difference is less than or equal to the predetermined threshold value and the MPEG transport stream is descrambled before returning to step of storing values of sync words by shifting values of a sync word register.

Synchronization method and apparatus of moving picture experts group transport stream for reducing initial delay

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.

Apparatus and method for creating widget in portable terminal

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.

Apparatus and method for receiving data in a wireless communication system using bit interleaving, symbol interleaving and symbol mapping

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.

Apparatus and method for improving channel change speed in digital broadcasting reception terminal

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.

Gap filler apparatus and method for providing cyclic delay diversity in a digital multimedia broadcasting system, and broadcasting relay network using the same

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 (N&#x2212;m+1)subcarrier from a first distorted symbol on an msubcarrier by a first compensation coefficient in an OFDM FFT signal of Nsubcarriers. 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.

Apparatus and method for optimally compensating for imbalance between in-phase and quadrature-phase in a zero-IF OFDM receiver

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.

Method and apparatus for performing channel compensation and symbol demodulation for coherent demodulation in an OFDM system

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. If the number of error checking-passed bit streams is larger than or equal to 2, the controller compares frame quality metrics for the bit streams and selects one bit stream having the maximum frame quality metric in order to acquire the control information.

Apparatus and method for receiving packet data control channel in a mobile communication system

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.

Apparatus and method for measuring a received signal to interference ratio in a mobile communication system

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.

Apparatus and method for removing DC offset in a frequency direct-conversion device

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.

Apparatus and method for detecting discontinuous transmission period in a CDMA mobile communication system

A mobile station of the mobile communication system measures signal energy on a traffic channel and interference energy on a sync channel to calculate SIR, compares the calculated SIR with a threshold, and then transmits the comparison results to a base station for a forward power control operation. To this end, a PN despreader multiplies a received signal by a unique PN code and outputs a PN despread signal. An orthogonal code despreader multiplies the PN despread signal by a sync channel orthogonal code and a traffic channel orthogonal code and outputs first and second orthogonal code despread signals. An interference energy processor measures interference energy by processing the first orthogonal code despread signal. A signal energy processor measures signal energy by processing the second orthogonal code despread signal. An SIR calculator calculates SIR depending on the measured signal energy and interference energy. The calculated SIR is compared with a predetermined threshold and the compared results are transmitted to the base station for the forward power control operation.

Forward power control apparatus and method for use in a multi-carrier communication system

A mobile communication system having an AGC (Automatic Gain Control) function includes an apparatus for adaptively controlling an output level of a local oscillator to reduce nonlinear distortion which may occur when a high-power RF signal is received or when it is necessary to transmit a high-power transmission signal. When a high-power RF signal is applied to a first stage in a receiving stage, the apparatus prevents the signal input to a reception AGC loop from being distorted by decreasing an output level of the local oscillator, which is provided to a down-converter. Further, when the output signal of a transmission stage has a high power level, the apparatus decreases the output level of a transmission AGC amplifier and instead increases the output level of the local oscillator, which is input to an up-converter located in an IF stage, so that it is possible to obtain a nonlinear distortion-reduced signal while obtaining the same output level.

Apparatus and method for reducing nonlinear distortion in an automatic gain control system

A device for linearizing a transmitter in a digital radio communication system. In the device, a predistortion lookup table stores predistortion data determined by measuring in advance distortion characteristics of the transmitter with respect to input baseband data. During transmission, the device synthesizes the input baseband data with the predistortion data to predistort the input data so as to compensate for the distortion characteristics caused by non-linear elements constituting the transmitter.

Device and method for linearizing transmitter in digital communication system

A digital automatic gain control device for use in a communication terminal of a mobile radio communication system employing a time-division duplex (TDD) transmission. A transmission power amplifier and a reception amplifier, which constitute the communication terminal, are fully composed of digital elements. In a transmission mode, a reception data latch is cleared to turn off the reception amplifier, so as to prevent a distortion of a modulated transmission signal due to regeneration and coupling of a modulated transmission waveform generated from a receiver. On the contrary, in a reception mode, a transmission data latch is cleared to prevent the carrier generated from the transmitter from being leaked toward a receiver, thereby preventing deterioration of a reception sensitivity of the receiver. Therefore, the transmission and reception gain can be accurately controlled based on the accurate timing control by the control processor.

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Seoul, South Korea

Ji-Won Ha