摘要:
The present invention relates to an apparatus and a method for compensating carrier feedthrough in a quadrature modulation system. In order to suppress the carrier feedthrough, and minimize and compensate the carrier feedthrough, differences of baseband differential input DC voltages in an in-phase as well as a quadrature-phase are simultaneously adjusted to 0 or a certain slight voltage difference by a simple analog circuit. Therefore, it is possible to suppress carrier feedthrough using a simple analog type apparatus for compensating carrier feedthrough, and simply achieve an apparatus for carrier feedthrough using a variety of quadrature modulators.
摘要:
The method for transmitting a signal of an orthogonal frequency division multiplexing type according to an exemplary embodiment of the present invention has a configuration allowing a radio unit (RU) to perform a component adding a compression component and a decompression component before/after a serial interface interlocking between a digital unit (DU) and the radio unit (RU) and a component inserting a cyclic prefix (CP) into a signal so as to secure orthogonality of an orthogonal frequency division multiplexing (OFDM) signal, in a structure in which a base station is physically divided into the DU and the RU.
摘要:
In a wideband mobile communication system, a signal transmitting apparatus separates an envelope curve signal which is size information and a phase signal which is phase information from a signal to transmit, and compares the envelope curve signal with a predetermined voltage. The signal transmitting apparatus performs active bias control that amplifies and outputs an envelope curve signal according to different driving voltages based on a comparison result, and supplies a bias voltage to a power amplifier that amplifies a phase signal based on the amplified signal.
摘要:
Disclosed are a signal distortion component adjusting apparatus and method capable of adjusting error vector magnitude of subcarriers of a predetermined position by adjusting a signal distortion component occurring while decreasing a peak to average power ratio (PAPR) in a communication system of an orthogonal frequency division multiplexing (OFDM) technology or an orthogonal frequency division multiple access (OFDMA) scheme, and a system using the same. The present invention includes a signal distortion component adjusting unit to add an additional signal distortion component Pe((n+N/2) % N) to a signal distortion component e(n) that is obtained by subtracting a threshold Th value, set to decrease peak power, from an absolute value of a time domain signal x(n) of an input signal, and to thereby adjust the signal distortion component. The present invention may transmit a highly reliable signal by adjusting error vector magnitude of subcarrier of a frequency domain.
摘要翻译:公开了一种信号失真分量调整装置和方法,其能够通过调整在正交频分复用的通信系统中降低峰均功率比(PAPR)的同时发生的信号失真分量来调整预定位置的子载波的误差矢量幅度 (OFDM)技术或正交频分多址(OFDMA)方案,以及使用它们的系统。 本发明包括一个信号失真分量调整单元,用于将附加信号失真分量Pe((n + N / 2)%N)加到通过将阈值Th值减去得到的信号失真分量e(n) 从输入信号的时域信号x(n)的绝对值减小峰值功率,从而调整信号失真分量。 本发明可以通过调整频域的子载波的误差矢量幅度来发送高度可靠的信号。
摘要:
The predistorter may include: a predistortion filter predistorting an input signal to provide an output signal; a predistortion output estimation unit estimating the characteristics of a nonlinear device based on a signal processed by the nonlinear device and the output signal, and calculating a desired output signal of the predistortion filter by using the estimated characteristics of the nonlinear device; and an adaptive algorithm driving unit comparing the output signal with the desired output signal to output an error as a comparison result, calculating a filter coefficient according to which the calculated error is minimized, and providing the calculated filter coefficient to the predistortion filter in order to update a filter coefficient of the predistortion filter.
摘要:
There is provided a method of manufacturing a lens, including applying a second lens material to a first lens member made of a first lens material; aligning and fixing a light shielding member to the second lens material; and further applying the second lens material to the first lens member and performing curing thereon to complete a second lens member.
摘要:
A maximum likelihood timing recovering unit is disclosed, which includes a sampler for over-sampling a matched filtering signal, first and second delay units for sequentially delaying a sampling signal of the sampler, a first decimeter for outputting a decision sample among an output signal of the first delay unit to a symbol decision unit, an adder for adding an output of the sampler and an output of the second delay unit, a multiplier for multiplying a decision symbol ak received in a preamble format and an output signal of the adder, a second decimeter for outputting a certain interval value based on a decision sample position among the output of the multiplier, an accumulator for accumulating the output of the second decimeter at a certain interval, and a voltage adjusting oscillator for providing an oscillation frequency generated using the output of the accumulator as an adjusting voltage to a 2Fs sampling clock signal of the sampler, for thereby recovering an optimum timing using a data over-sampled by adjusting an oscillation speed of a voltage adjusting oscillator by two times.
摘要:
There is provided a method of manufacturing a lens, including applying a second lens material to a first lens member made of a first lens material; aligning and fixing a light shielding member to the second lens material; and further applying the second lens material to the first lens member and performing curing thereon to complete a second lens member.
摘要:
Disclosed is a technology for performing a communication using an ultrasonic wave in an environment where an electromagnetic shielding is so severe that a wireless communication using an electromagnetic is difficult. In the environment where the electromagnetic shielding is severe, an ultrasonic terminal according to the present invention may transmit the ultrasonic wave using a solid structure as a medium, and an ultrasonic base station may receive the ultrasonic wave using the solid structure as the medium.
摘要:
There is provided a method of manufacturing a lens, including: forming a first lens layer having a protrusion and a groove part formed on a first surface thereof; forming a light shielding layer on the first surface; and forming a second lens on the first surface.