摘要:
A direct sequence spread spectrum (DSSS) transceiver including a DSSS transmitter and a DSSS receiver, wherein the DSSS transmitter includes: an integral code mapping unit mapping source bit data in one of 2N (N is a natural number) of predetermined symbols by N bits and mapping the symbol in one of integral code words that are obtained by previously integrating each of 2N of bi-orthogonal code words; and a radio frequency (RF) transmitting unit transmitting the integral code words mapped by the integral code mapping unit over an RF carrier wave, and the DSSS receiver includes: an RF receiving unit removing an RF carrier wave from an RF signal from the RF transmitting unit and converting an analog signal obtained by removing the RF carrier wave from the RF signal into a digital signal; a differential circuit unit differentiating and converting the digital signal from the RF receiving unit into bi-orthogonal code words; and a symbol detection unit detecting a symbol corresponding to a maximum value of correlation values between bi-orthogonal code word from the differential circuit unit and a plurality of predetermined reference code words.
摘要:
A direct sequence spread spectrum (DSSS) transceiver including a DSSS transmitter and a DSSS receiver, wherein the DSSS transmitter includes: an integral code mapping unit mapping source bit data in one of 2N (N is a natural number) of predetermined symbols by N bits and mapping the symbol in one of integral code words that are obtained by previously integrating each of 2N of bi-orthogonal code words; and a radio frequency (RF) transmitting unit transmitting the integral code words mapped by the integral code mapping unit over an RF carrier wave, and the DSSS receiver includes: an RF receiving unit removing an RF carrier wave from an RF signal from the RF transmitting unit and converting an analog signal obtained by removing the RF carrier wave from the RF signal into a digital signal; a differential circuit unit differentiating and converting the digital signal from the RF receiving unit into bi-orthogonal code words; and a symbol detection unit detecting a symbol corresponding to a maximum value of correlation values between bi-orthogonal code word from the differential circuit unit and a plurality of predetermined reference code words.
摘要:
There are provided a power factor correction apparatus, a direct current/direct current (DC/DC) converter, and a power supplying apparatus, capable of preventing unstable feedback control due to a ripple component by controlling power switching based on a median value between a maximum value and a minimum value of a voltage level of the output power that is received as feedback. The power factor correction apparatus includes a power factor corrector switching input power and correcting a power factor thereof; and a controller detecting a voltage level of power factor-corrected power and controlling the switching of the power factor corrector, based on a median value between a maximum value and a minimum value of the voltage level of the power factor-corrected power detected for a predetermined period of time.
摘要:
Provided is a synchronization device for wireless communication packets, the synchronization device including an A/D (analog/digital) converter that converts an analog input signal applied from outside into a digital signal; a correlation calculating section that is connected to the A/D converter and correlates the converted input signal with a preset reference code so as to calculate a correlation value; a threshold setting section that is connected to the correlation calculating section and sets a threshold value of the correlation value; a maximum correlation detecting section that is connected to the correlation calculating section and the threshold setting section, compares the correlation value with the threshold value, detects the position of the maximum correlation value within each symbol of the input signal when the correlation value is larger than the threshold value, and judges whether a difference in position between the maximum correlation values of consecutive symbols is equal to the period of one symbol or not; a preamble detecting section that is connected to the correlation calculating section and the maximum correlation detecting section and outputs a preamble detection signal when the difference is equal to the period of one symbol; and a data detecting section that receives data of the input signal when the preamble detection signal is applied.
摘要:
There are provided a system on chip (SoC) with a low power mode and a method of driving the SoC, the SoC including: a power part supplying a main clock signal and controlling analog and digital power supply at a normal mode and supplying a sub clock signal and turning analog power off at a low power mode; a radio frequency (RF) part generating the main clock signal at the normal mode and stopping operation at the low power mode, under the control of the power part; and a control part operating according to the main clock signal at the normal mode and operating according to the sub clock signal, under to the control of the power part.
摘要:
There is provided a dual mode WPAN transceiver including a dual mode WPAN transmitter and a dual mode WPAN receiver. In the dual mode WPAN transceiver, the dual mode WPAN transmitter includes a low-speed spreading transmission block spreading low bit-rate data corresponding to a low data rate in low data rate mode, and a high-speed encoding transmission block encoding high bit-rate data corresponding to a high data rate in high data rate mode, and the dual mode WPAN receiver includes an A/D block converting analog I and Q signals into digital I and Q signals, a differential block obtaining a phase difference between the digital I and Q signals from the A/D unit and complex signals adjacent thereto to offset phase errors of the digital I and Q signals, a low-speed despreading reception unit despreading the digital I and Q signals differentiated by the differential block to detect low bit-rate data in low data rate mode, and a high-speed decoding reception unit decoding the digital I and Q signals differentiated by the differential block to detect high bit-rate data.
摘要:
The present invention relates to a method for detecting interference and an interference detecting device for a wireless communication capable of improving detection accuracy of an interference signal in a wireless communication device without influencing network operation while the interference signal is detected; and, more particularly, to a method for detecting interference and an interference detecting device for a wireless communication to determine an interference signal by increasing an interference packet count according to an RSSI value, its own packet detection, gain reduction, deterioration of signal quality, the number of the same symbols, and so on and comparing an increased interference packet count value with a threshold value by using each ZigBee device as a main constituent of interference detection unlike a conventional method for detecting interference in which a ZigBee coordinator or a ZigBee router is a main constituent of interference detection.
摘要:
An apparatus and a system for viewing a 3D image including a synchronization signal receiver for receiving 3D image synchronization signal; a 3D control signal generator for generating left-eye glass control signal and a right-eye glass control signal in accordance with the synchronization signal received; a left-eye glass that opens or intercepts light transmitted to the left-eye glass; a right-eye glass that opens or intercepts light transmitted to the right-eye glass; a central processor that controls operation of the 3D control signal generator and transmits the synchronization signal to the 3D control signal generator; and a power controller that connects or intercepts power supplied to the synchronization signal receiver and the central processor. The power consumption of the apparatus is minimized by supplying power to the synchronization signal receiver and the central processor at a time when the synchronization signal is received and power is intercepted during the rest period.
摘要:
A preprocessing unit samples and digitalizes analog signal. A differential operation unit delays digitalized signal for a predetermined period and differentiates delayed signals. A correlation unit correlates differentiated signal with a plurality of predetermined PN code sequences. A setting unit includes a shift register having a plurality of storage locations for shifting the correlation values and sequentially storing shifted correlation values at the storage locations, respectively, a detector including the determination slots for detecting the storage location of the maximum value, and a slot setter for comparing the storage location of the maximum value from the detector with the predetermined reference storage location and shifting the determination slots by the difference therebetween. A demodulation value estimation unit estimates, as a demodulation value of the received analog signal, a symbol of a PN code sequence corresponding to the maximum value from the shifted determination slots.
摘要:
There is provided an RF receiver recovering timing offset by shifting timing slots in response to timing offset occurring when a signal is sampled. An RF receiver having timing offset recovery function according to an aspect of the invention includes: a preprocessing unit sampling and digitalizing an analog received signal; a differential operation unit delaying the digitalized received signal from the preprocessing unit for predetermined periods of time and differentiating the delayed signals; a correlation unit correlating the differentiated received signals from the differential operation unit with a plurality of predetermined PN code sequences and sequentially outputting correlation values; a setting unit sequentially storing the correlation values from the correlation unit, detecting a maximum value among the stored correlation values, and shifting a plurality of determination slots by a difference between a storage location of the detected maximum value and a reference storage location; and a demodulation value estimation unit estimating as a demodulation value of the received signal, a symbol of a PN code sequence corresponding to the maximum value from the shifted determination slots.