Abstract:
PURPOSE: A distortion compensation apparatus, a signal transmitting device, and a method thereof are provided to prevent performance degradation because of calculation error during a process of extracting distortion information. CONSTITUTION: A distortion compensation apparatus(12) recompenses nonlinearly characteristic of a nonlinear device(10) for wireless telecommunication. The nonlinear device outputs linear signal through a transmission antenna(14) using a distortion compensation apparatus. The distortion compensation apparatus uses a signal predistortion mode in order to recompense the nonlinear characteristic of the nonlinear device. The distortion compensation apparatus comprises an additional signal applying unit(120), a predistortion unit(122), and an indirect adaptation controller(124).
Abstract:
PURPOSE: A broadband local wireless communication method and method thereof are provided to enlarge communication arrival distance. CONSTITUTION: A source device(110) searches a list of relay devices(130,131,132) in a basic service set. A channel state between a source device and a relay device and a channel state between a target device(140) and relay device are confirmed. A relay device to operate is selected as a relay between the source device and the target device. A relay link setting request message is transmitted to the selected relay device. A relay link is set through the selected relay device.
Abstract:
PURPOSE: A wireless communication system capable of reducing power consumption and a method thereof are provided to reduce power consumption. CONSTITUTION: A receiving terminal receives scheduling information associated with data transmission and reception of a transmitting terminal. The receiving terminal directly performs communication with the transmitting terminal by referring to the scheduling information. A scheduling information includes information about the data transmission period. A controller(220) controls a communication unit(210) in order to be operated in a sleep mode excluding the data transmission period.
Abstract:
PURPOSE: A wireless relay channel measuring device is provided to measure a wireless relay channel about a wireless link between a base station, relay and a terminal. CONSTITUTION: According to a user input, a control unit(110) establishes one operating mode among a base station mode, a relay mode or a terminal mode. According to the fixed operating mode, the control unit performs transceiving control of a signal for wireless relay channel measurement.
Abstract:
PURPOSE: A bandpass delta sigma signal transmitter which uses a band pass delta signal modulator is provided to prevent the unnecessary quantization noise of a power amplifier. CONSTITUTION: A digital IF(Intermediate Frequency) unit(320) converts an I/Q signal which is received from a baseband to an IF signal. A multi-bit band pass delta sigma modulating unit(330) outputs the IF signal through the sampling of the IF signal. An RF up converter(340) converts the quantized IF signal into the quantized RF signal. A power amplifier(350) amplifies the quantized RF signal.
Abstract:
PURPOSE: A multiple clock synchronizing method and apparatus thereof are provided to synchronize the clock of a high layer in a multiple clock communication environment which uses heterogeneous clock. CONSTITUTION: A lower layer of a terminal performs synchronization with a lower layer of the other terminal(410). The lower layer of the terminal transmits the synchronizing signal with the higher layer of the terminal. The higher layer of the terminal stores synchronization information(420). The higher layer of the terminal receives the synchronization information from the other terminal. The higher layer of the terminal compares the received synchronization information with the stored synchronization information.
Abstract:
PURPOSE: A dual-band wideband local signal generating device is provided to differently form a signal generated in an oscillator and a local signal supplied to a transceiving terminal, thereby reducing VCO pulling. CONSTITUTION: Oscillation units(101,102,103) generate a positive in-phase signal, a negative in-phase signal, a negative orthogonal phase signal, and a positive orthogonal phase signal. Frequency de-multipliers(104,105) generate an RF signal by de-multiplying frequencies of generated IP and IN signals. A poly phase filter(107) generates LO signal of IP, IN, QP, and QN. Switch units(108,109) select a high-band frequency signal or a low band frequency signal. A single side band mixer(106) generates a local signal by the sum or the subtraction of the de-multiplied signal and the selected signal.
Abstract:
PURPOSE: A preamble generating method and a device for a station, and a data frame generating method are provided to supply a preamble which can distinguish a channel about a plurality of station and can minimize the effect to a system. CONSTITUTION: A base sequence for channel estimation is generated(S201). Antenna channel estimation sequence about at least one antenna of a station is generates(S203). A preamble is generated by allocating at least one modification sequence in a frequency area about at least one time section(S205). The modification sequence uses a control sequence for the base sequence, the antenna channel estimation sequence, and channel estimation. The control sequence is for identifier recognition of a code word or an access point of a constant set length.
Abstract:
PURPOSE: A method and an apparatus for generating a data frame, a method and an apparatus for transmitting/receiving a data frame in a wireless communication system are provided to reduce the amount of payload by supplying a data frame to firstly decode a header including segment information. CONSTITUTION: In a method and an apparatus for generating a data frame, a method and an apparatus for transmitting/receiving a data frame in a wireless communication system, a data frame comprises a FL PHY header(201), a VL PHY header(203), a ATIF(205), an HCSs(207,213), a RS parities(209,215), and a MAC header(211). 5 FL PHY headers is firstly allocated to the data frame, and then VL PHY header and the ATI are allocated to a data frame sequentially. The HCS including an error detection code is allocated to the data frame, and then RS parity including the error correction code is allocated to the data frame. The HCS and the RS parity are allocated to the data frame.
Abstract:
PURPOSE: A standby mode supporting method in wireless LAN-system is provided to track the location of the terminal in case the terminal moves under operation of standby mode. CONSTITUTION: A terminal transmits a request message for waiting mode start to AP(Access Point)(S200). The terminal starts the standby mode(S220). The AP transmits a paging indication message including traffic arrival information to the terminal(S230). The terminal transmits a request message for waiting mode termination to the AP(S240). The AP transmits a response message about the standby mode termination to the terminal(S250).