摘要:
The present invention relates to a device for compensating a radio frequency distortion caused by a sample/hold operation of a digital/analog converter in an orthogonal frequency division multiplexing (OFDM) transmission system, and a method thereof. In a digital transmission system, an edge frequency signal of a transmission signal band is distorted by a sample/hold operation of a digital/analog converter such that a signal attenuation is generated at a frequency domain by a sync function having a zero point at a sample frequency of a transmission signal. In the present invention, the signal distortion may be compensated by multiplying a coefficient of an inverse sync function by a signal weight value at the frequency domain, and it may be compensated by using a single multiplier and a lookup table storing the coefficient of the inverse sync function.
摘要:
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.
摘要:
The present invention relates to a device for compensating a radio frequency distortion caused by a sample/hold operation of a digital/analog converter in an orthogonal frequency division multiplexing (OFDM) transmission system, and a method thereof. In a digital transmission system, an edge frequency signal of a transmission signal band is distorted by a sample/hold operation of a digital/analog converter such that a signal attenuation is generated at a frequency domain by a sync function having a zero point at a sample frequency of a transmission signal. In the present invention, the signal distortion may be compensated by multiplying a coefficient of an inverse sync function by a signal weight value at the frequency domain, and it may be compensated by using a single multiplier and a lookup table storing the coefficient of the inverse sync function.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
The present invention relates 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.
摘要:
A repeating apparatus in a wireless communication system includes: a signal detection unit configured to receive a signal from a base station or a mobile station and detect strength of the signal; a control unit configured to compare the signal strength detected by the signal detection unit with signal strength predetermined by the system and provide comparison information; and an output signal control unit configured to receive the comparison information from the control unit and adjust and amplify gain of a signal transmitted to the base station or the mobile station.
摘要:
Provided is an apparatus and method for controlling power in a mobile communication system. The apparatus includes a moving speed measuring unit for measuring a moving speed of the terminal, a Channel Quality Indicator (CQI) processing unit for requesting a base station to adjust a CQI report frequency when the moving speed measured by the moving speed measuring unit exceeds a threshold value, and determining a CQI report frequency based on information on the CQI report frequency received from the base station to report CQI, and a power controller for performing a power control in response to a power control signal created by the CQI reported from the base station.