| Patent application number | Description | Published |
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| 20090154617 | AUTOMATIC GAIN CONTROL DEVICE, SIGNAL RECEIVING APPARATUS, AND SIGNAL RECEIVING METHOD - A signal receiving apparatus according to an embodiment of the present invention includes: an amplifier that controls a gain according to a gain control signal and amplifies a received signal to generate an amplified signal; an analog-to-digital (A/D) converter that converts the amplified signal into a digital signal; a Fourier transform unit that performs Fourier transform of the digital signal to a frequency domain signal to generate a Fourier transform signal; a demodulator that demodulates the Fourier transform signal to generate a demodulated signal; and an automatic gain control unit that divides the Fourier transform signal into a noise period and a symbol period, calculates the signal level of the noise period based on the signal level of the symbol period, and generates the gain control signal according to the signal levels of the symbol period and the noise period. Accordingly, when a non-cyclic burst signal is received, the non-cyclic burst signal is divided into a signal presence period and a signal absence period, and the gain is only controlled by using the signal presence period. Therefore, accuracy of the signal level can be secured, and the signal level of the symbol can be calculated in the frequency domain, thereby reducing complexity. | 06-18-2009 |
| 20100118744 | WIRELESS TRANSCEIVER SYSTEM FOR SUPPORTING DUAL MODE - The present invention relates to a wireless transceiver system for supporting a dual mode, and more particularly to a wireless transceiver system for supporting a dual mode that simultaneously supports the Frequency Division Duplex (FDD) method and the Time Division Duplex (TDD) method in a certain frequency band. The present system supports the FDD system conducting transmission and reception simultaneously by using different frequency bands for transmission and reception as well as the TDD system temporally alternating transmission and reception by using the common frequency band among an upper frequency band and a lower frequency band used in the FDD system as well as another frequency band adjacent thereto, thereby selectively supporting both of the two communication systems in a wireless transceiver system. Therefore, efficient use of various wireless communication standards and the limited frequency resource is provided, and on this basis, an efficient application of all wireless transceiver systems adopting the TDD system and the FDD system as well as the mobile communication base station and the terminal is provided. | 05-13-2010 |
| 20100135421 | APPARATUS AND METHOD FOR REDUCING PEAK TO AVERAGE POWER RATION IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEM - An apparatus for reducing PAPR (Peack to Average Power Ratio) in an OFDM (Orthogonal Frequency Division Multiplexing) system includes: an IFFT (Inverse Fast Fourier Transform) unit for performing an IFFT on an input data stream modulated using a specific constellation to generate time-domain signals; a time-domain clipping unit for performing a time-domain clipping on the time-domain signals at a clipping level determined by characteristics of the time-domain signals; an FFT (Fast Fourier Transform) unit for performing an FFT on the clipped time-domain signals to generate frequency-domain signals; and a frequency-domain clipping unit for performing a frequency-domain clipping on the frequency-domain signals. The time-domain clipping reduces in the OFDM system, and the frequency-domain clipping reduces distortions generated by the time-domain clipping. | 06-03-2010 |
| 20100146021 | MODULAR-3 CALCULATION APPARATUS AND METHOD - A modular-3 calculation method for binary number includes: determining whether two 1s consecutive from MSB exist in a binary number, when a target value for modular-3 calculation is inputted, and generating a first binary number by substituting the two 1s with 0 whenever the consecutive two 1s exist; performing a modular-3 calculation on the first binary number; and determining the result of the modular-3 calculation. | 06-10-2010 |
| 20110063026 | PRE-DISTORTION APPARATUS OF POWER AMPLIFIER AND METHOD THEREOF - A pre-distortion apparatus of a power amplifier includes: a pre-distortion unit configured to generate a pre-distorted signal of an input signal by calculating a magnitude of the input signal and outputting a complex correction coefficient corresponding to the calculated magnitude of the input signal, and provide the generated pre-distorted signal as an input of the power amplifier; and a complex correct coefficient update unit configured to generate an error signal by comparing an output signal of the power amplifier with the input signal and updating the complex correction coefficient to minimize a magnitude of the generated error signal, wherein the pre-distortion unit provides a constant bias value corresponding to the magnitude of the input signal as a bias of the power amplifier while updating the complex correction coefficient. | 03-17-2011 |
| 20110237210 | APPARATUS AND METHOD FOR CONTROLLING GAIN OF POLAR TRANSMITTER - Disclosed is an apparatus for transmitting complex signals in a wireless communication system. The present invention, there is provided a method for controlling gain according to a magnitude change of output signals in a polar transmitter including an amplification unit having two or more amplification degrees, the method includes processes to control an output level of a modulated signal when a output-required power of transmission signals are less than a predetermined threshold value, and to perform a basic amplification through the amplification unit; to amplify the amplification unit at a first amplification level when the output-required power of the transmission signals is equal to or greater than a predetermined first threshold value and is less than a predetermined second threshold value; and to amplify the amplification unit at a second amplification level when the output-required power of the transmission signal is equal to or greater than the second threshold value. | 09-29-2011 |
| Patent application number | Description | Published |
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| 20100056083 | RADIO FREQUENCY CALIBRATION APPARATUS AND METHOD FOR MULTI-ANTENNA MOBILE COMMUNICATION SYSTEM - There is provided to an RF calibration apparatus and method for a multi-antenna mobile communication system, which calibrates a phase error and gain error of an RF path by calculating the minimum value of a sum of an initialized reference signal and a comparison signal by a simple operation and controlling the phase value of a phase converter and the gain of a variable amplifier on the RF path, in calibrating the RF path of a multi-antenna mobile communication system of a TDD (Time Division Duplexing) type or FDD (Frequency Division Duplexing) type. | 03-04-2010 |
| 20100128775 | APPARATUS AND METHOD FOR TRANSMITTING SIGNAL IN WIRELESS COMMUNICATION SYSTEM - Disclosed are an apparatus and method for transmitting a signal in a wireless communication system. The apparatus includes a controller for receiving power control information of a baseband signal, deciding an output mode, and providing an output mode signal, a signal converter for receiving the baseband signal outputting a phase signal, and outputting an envelope signal when the output mode signal indicates a first output mode, a phase modulator for up-converting the phase signal, and an amplifier for combining the envelop signal and the up-converted phase signal for the first output mode and amplifying the combined signal. | 05-27-2010 |
| 20100136939 | GAIN CONTROL APPARATUS AND METHOD IN RECEIVER OF MULTIBAND OFDM SYSTEM - A gain control apparatus in a receiver of multiband OFDM system includes: an amplifier amplifying a received signal based on a first auto gain control signal; an analog-to-digital converter for converting the amplified signal into a digital signal; band reception signal extractor for extracting a signal of a desired reception band from the converted digital signal for each reception band, and controlling gain of the extracted signal according to a second auto gain control signal; a reception power detector for detecting a reception power value of whole band from the converted digital signal; and a multiband integration baseband processor for generating the first auto gain control signal by using the detected reception power value of the whole band, and generating the second auto gain control signal to be provided to the band reception signal extraction units, resource allocation information for each band and a reception power for each reception band. | 06-03-2010 |
| 20100150262 | APPARATUS AND METHOD FOR AMPLIFYING SIGNAL AND WIRELESS TRANSMITTER USING THE SAME - Provided are a signal amplifying apparatus and method and a wireless transmitter using the same. The signal amplifier includes a polar coordinate converter configured to output an envelope signal and a phase signal by converting a signal to a polar coordinate, a multilevel quantizer configured to output a multilevel quantized signal by quantizing the envelope signal to multiple levels, an amplification state controller configured to control an amplification state using the multilevel quantized signal, and a power amplifier configured to amplify the phase signal according to the controlled amplification state. | 06-17-2010 |
