摘要:
Provided is a link adaptation method and apparatus in wireless communication system. The method, includes: amplifying a received signal; converting the amplified signal into a digital signal; calculating digital signal strength; and calculating the received signal strength based on the digital signal strength and a gain of said amplifying a received signal.
摘要:
Provided are a transmitter and receiver for a high throughput wireless communication system using a multiple antenna, a method thereof, and a digital intermediate frequency (DIF) transmission signal processing method for the same. The transmitter, includes: a baseband transmitting unit for processing a transmission signal by performing a Media Access Control (MAC) protocol process on transmission data and dividing the transmission data into n band signals where n is a predetermined natural number in a physical layer process; a DIF transmitting unit for integrating transmission signals of each band transmitted from the baseband transmitting unit and outputting m channels where m is a predetermined natural number; and a Radio Frequency (RF) transmitting unit for modulating each channel signal transmitted from the DIF transmitting unit into an RF signal and emitting the signal through the multiple antenna.
摘要:
An apparatus for detecting a packet end point in a wireless communication system includes: a signal reception unit configured to receive a signal from an outside, convert the signal into a baseband signal, perform analog-digital conversion of the baseband signal, and perform a digital front end; a storage unit configured to store an output of the signal reception unit; a frequency offset estimation unit configured to estimate a frequency offset using the output of the storage unit; a frequency offset correction unit configured to compensate for a frequency error using the estimated frequency offset; an offset correlation unit configured to calculate correlation of the frequency offset and a cyclic prefix; an auto-correlation operation unit configured to calculate auto-correlation of the cyclic prefix; and a packet end detection unit configured to check a packet end point using the auto-correlation.
摘要:
An apparatus for detecting a packet end point in a wireless communication system includes: a signal reception unit configured to receive a signal from an outside, convert the signal into a baseband signal, perform analog-digital conversion of the baseband signal, and perform a digital front end; a storage unit configured to store an output of the signal reception unit; a frequency offset estimation unit configured to estimate a frequency offset using the output of the storage unit; a frequency offset correction unit configured to compensate for a frequency error using the estimated frequency offset; an offset correlation unit configured to calculate correlation of the frequency offset and a cyclic prefix; an auto-correlation operation unit configured to calculate auto-correlation of the cyclic prefix; and a packet end detection unit configured to check a packet end point using the auto-correlation.
摘要:
Provided are apparatus and method for receiving signals in a wireless communication system. A receiving apparatus including a plurality of variable gain amplifier units configured to respectively control the gains of radio frequency (RF) signals received respectively through a plurality of antennas, and a plurality of analog-to-digital converters configured to respectively convert the output signals of the respective variable gain amplifiers into digital signals, includes: an automatic gain controller configured to calculate the gain values of the respective gain control amplifier units by receiving the digital signals outputted from the respective analog-to-digital converters, select the minimum gain value among the calculated gain control values, and calculate the differences between the minimum gain value and the other gain values; and a noise matching amplifier configured to attenuate the digital signals outputted from the respective analog-to-digital converters according to the calculated difference values.
摘要:
Provided are apparatus and method for receiving signals in a wireless communication system. A receiving apparatus including a plurality of variable gain amplifier units configured to respectively control the gains of radio frequency (RF) signals received respectively through a plurality of antennas, and a plurality of analog-to-digital converters configured to respectively convert the output signals of the respective variable gain amplifiers into digital signals, includes: an automatic gain controller configured to calculate the gain values of the respective gain control amplifier units by receiving the digital signals outputted from the respective analog-to-digital converters, select the minimum gain value among the calculated gain control values, and calculate the differences between the minimum gain value and the other gain values; and a noise matching amplifier configured to attenuate the digital signals outputted from the respective analog-to-digital converters according to the calculated difference values.
摘要:
Provided are a receiving apparatus for a multiple input multiple output (MIMO) system and a method thereof. The receiving apparatus includes a QR decomposing unit for calculating a single (Q) matrix vector and an upper triangle (R) matrix vector for a receiving signal vector; a first symbol estimation unit for estimating predetermined symbols using the calculated Q matrix vector and R matrix vector; a log likelihood ratio (LLR) calculating unit for calculating log likelihood ratios of unit bits for the estimated symbols; an interference removing unit for receiving a decoded signal that is decided using the calculated log likelihood ratios and removing interference from the receiving signal vector; and a second symbol estimation unit for linearly estimating remaining symbols for the interference removed signal.
摘要:
Provided are apparatus and method for transmitting and receiving data for a wireless communication system. The method includes generating a first aggregation packet by controlling the number of preambles or by controlling a size of a packet according to a channel state of a channel formed to at least one reception terminal or according to a state of the reception terminal, and transmitting the first aggregation packet to the reception terminal.
摘要:
A method for estimating timing offset in an OFDM wireless communication system using preamble and pilot includes: estimating a carrier offset by using preamble included in a currently received OFDM packet and estimating a first timing offset based on the estimated carrier offset to thereby produce a first timing offset estimation value; estimating a second timing offset to thereby produce a second timing offset estimation value by transforming the OFDM packet into signals of frequency domain and using a pilot signal of the frequency-domain signals; checking a channel condition based on packet error information of a previously received packet to thereby produce error condition information, and selecting one between the first timing offset estimation value and the second timing offset estimation value based on the error condition information; and compensating data signals for timing offset among the frequency-domain signals the based on the selected timing offset estimation value.
摘要:
Provided are apparatus and method for transmitting and receiving data for a wireless communication system. The method includes generating a first aggregation packet by controlling the number of preambles or by controlling a size of a packet according to a channel state of a channel formed to at least one reception terminal or according to a state of the reception terminal, and transmitting the first aggregation packet to the reception terminal.