Samsung Electronics Co., Ltd.

Seong-Kyu Hwang

Jae-Hawk Lee

Jeoung-Gil Lee

Chae-Man Lim

Yong-Serk Kim

Hyun-Kuk Choi

Dong-Ryeol Ryu

Nam-il Lee

Sang-Won Kang

Sang-hyun Chi

An apparatus and method for adjusting a desired expression section according to input bit values in a mobile communication system that expresses only a defined partial section of the input bit values in order to make the number of output bits be less than the number of the input bits, and maps bit values included in unexpressed sections to a specific value is provided. In the apparatus and method, a measurer divides possible output bit values into at least three sections, and measures output frequencies of output bits for the respective sections for a predetermined time. A controller adjusts the desired expression section, when an output frequency for a specific section is greater than output frequencies for other sections.

Apparatus and method for adjusting an input range for a soft-decision decoder

An apparatus and method of receiving multi-path signals in a direct sequence Code Division Multiple Access (CDMA) mobile communication system is disclosed. Timing control signals from respective fingers are collected, and relations among positions of time delays where the respective fingers intend to perform a demodulation are analyzed. If it is determined that the time delay position for a specified finger approaches the time delay position of the finger allocated with an adjacent multi-path as close as a threshold value, the distance between the time delay positions is compulsorily kept as the threshold value. This can be effected by making the timing control signal of the finger allocated with the adjacent multi-path be equally used in the specified finger.

Rake receiving apparatus and method in a direct sequence CDMA mobile communication system

A fast search method for searching for an optimum codeword for nearest neighbor vector quantization. An upper boundary value and a lower boundary value between which an optimum codeword will exist in a codebook are calculated using a distortion of a designated element in an input vector and an experimentally determined threshold. Further, a start point and an end point for codebook search are determined using a binary search method from a codebook rearranged in descending order, and a full search scheme is applied only within a search range calculated by the determined start point and end point, thereby determining an optimum codeword for nearest neighbor vector quantization.

Fast search method for nearest neighbor vector quantization

A transmitter for a multiple frequency radio communication system provides a capability for filtering spread spectrum signals of a multiple frequency system by using one lowpass filter, and variably controlling the sampling speed when converting the lowpass filtered digital signal into an analog signal. In one embodiment, the transmitter comprises a clock generating section for receiving a predetermined bandwidth selecting control signal and then generating a clock having a speed in proportion to the predetermined bandwidth, a multiplexing section for inserting zero into a signal, spread modulated in a desired bandwidth, the bandwidth being selected from the plurality of frequency bandwidths according to the predetermined bandwidth selecting control signal, to produce an oversampled signal, a lowpass filter for receiving the clock and for lowpass filtering an output signal of the multiplexing section, a digital/analog converter for receiving the clock and then converting an output signal of the lowpass filter into an analog signal at the clock speed, and a switch for receiving the bandwidth selecting control signal and then switching an output of the digital/analog converter to a corresponding one of a plurality of intermediate frequency circuits according to the selected bandwidth.

Transmitter of multiple frequency radio communication system

A method for increasing information throughput in a transmitter of a digital mobile telecommunication system is provided. The method includes the step of implementing error correction with respect to a traffic channel frame having user service information to generate CRC bits for the user service information of the traffic channel frame. The CRC bits are inserted into a control channel frame. The traffic channel frame and the control channel frame having the inserted CRC bits are transmitted at a radio frequency.

Transmitter with increased traffic throughput in digital mobile telecommunication system and method for operating the same

A circuit for detecting a frequency correction burst in a TDMA digital mobile communication system. The circuit comprises a first multiplier for inputting I-channel data modulated by a continuous phase shift key and multiplying the inputted I-channel data by a sine wave frequency of the frequency correction burst to produce a first channel signal I1(nT); a second multiplier for inputting Q-channel data modulated by the continuous phase shift key and multiplying the inputted Q-channel data by the sine wave frequency of the frequency correction burst to produce a second channel signal Q1(nT); a low-pass filter for lowpass-filtering the first and second channel signals I1(nT) and Q1(nT) to produce first and second filtered channel signals I2(nT) and Q2(nT); a first energy estimation unit for estimating energies of the first and second channel signals I1(nT) and Q1(nT), respectively to generate a first instantaneous signal energy E.sub.p (nT); a second energy estimation unit for estimating energies of the first and second channel signals I1(nT) and Q1(nT), respectively to generate a second instantaneous signal energy E.sub.q (nT); a normalization unit for normalizing the first instantaneous signal energy E.sub.p (nT) to the second instantaneous signal energy E.sub.q (nT) to generate a normalized signal G(nT); and a burst discriminator for detecting only a frequency correction burst from the normalized signal G(nT).

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Seoul, South Korea

Seong-Kyu Hwang