查询词典 frequency bandwidth

Speakers import modules with a combination of : titanium membrane Treble, and with fiberglass trumpet, better high frequency extension stronger sense of space; Bass modules using imported pulp Senate carbon fiber, rigid speaker cone greatly strengthened, the effective bandwidth within a more flat frequency response and bass modules using aluminum frame and aluminum wire voice coil. Shaker skeleton of the United States military material, light weight, high efficiency, so that the audio sound pressure increased significantly. more males, bass magnetic circuit using high efficiency of the cooling system to ensure that the speakers have very good heat dissipation, reduce distortion, effectively reduce the power to the compression.

跟进口喇叭单元的结合：采用钛膜高音，配以玻璃钢号角，使高频得到更好的延伸，空间感更强；低音单元采用进口纸浆参碳纤维，纸盆刚性大大加强，在有效的频宽内有更平坦的频率回应，低音单元采用铝盆架和铝扁线音圈，音圈骨架为美国军事物料制造，品质轻，效率高，使音频的声压大幅度提高，更具爆发力，低音磁路采用高效率的冷却系统，保证了扬声器有很好的散热，减少失真，有效降低功率的压缩给。

Its very high bandwidth means that frequency doublers can be eliminated in many high frequency systems, simplifying system architecture and reducing cost.

它有高的带宽，意味着在高频系统中能除倍频器，使系统简化并可降低生产成本。

In wireless broadband digital communication, Inter-Symbol Interference caused by time disperse of radio channel is one of main factors that limit bandwidth of communicated information and system performance of communication. In receiver, Orthogonal Frequency Division Multiplexing system can easily cancel ISI and equalize frequency-selective fadings that are both caused by time disperse of radio channel.

在这一系统中，无线信道时延扩展引起的符号间干扰是限制传输性能和信息速率的主要因素之一；而在消除符号间干扰和均衡由无线信道时延扩展引起的频率选择性衰落方面，正交频分复用(Orthogonal Frequency Division Multiplexing，OFDM)技术具有明显优势。

At last, the frequency spectrum analysis shows that the four-winged chaotic attractor has extremely wide frequency bandwidth compared with that of the Lorenz system and Chua circuit, which is important in practical applications in communication encryption etc.

最后，通过比较该四翼混沌吸引子的系统、Lorenz系统、Chua氏电路等混沌信号的频谱发现，四翼混沌吸引子的系统信号具有极宽的频谱带宽，该特性在通讯加密等工程应用中具有重要价值。

In this paper, for the first time, the impact of the noise frequency-modulated signal to a wide band linear frequency modulation matched filter is studied for different modulation noise variance and bandwidth.

研究了噪声调频信号中调制噪声方差及带宽的选择对宽带线性调频匹配滤波器的影响。

First, it gests the bandwidth parameter and center frequency of Gabor filter based on human vision and the size of texture image, constructing the multichannel Gabor filters and extracting the Gabor multitemporal and multidirectional energy features of image in the time and frequency domain and implementing nonlinear transform and Gauss lowpass filtering in the feature space.

首先根据人类视觉特性选定Gabor滤波器的频率带宽参数，利用图像大小确定滤波器的中心频率，构造一组多通道的Gabor滤波器在时域和频域中提取图像多方向和多分辨率的Gabor能量特征，对特征空间进行非线性变换和Gauss滤波处理，最后通过Kmeans方法实现纹理图像的分割。

In the last new years , as the demands of wireless communication system grows rapidly , the bands of microwave frequency had been saturated with various communication applications . To achieve wider spectrum for high-speed and high-capacity transmission , bands of millimeter-wave frequency are the solution of this problem . The advantage of MMW wireless communication systems is wider bandwidth comparing with microwave communication systems . To utilize the spectrum efficiently , many methods of complexly digital modulation is proposed . The more complex modulation , the higher linearity is required , and more various phase of signals are required to accomplish process of modulation . Therefore high-linearity and quadrature-phase modulator and demodulator are the emphasis of this thesis . For high level of integration , high performance and low cost , this chip is fabricated by the complementary oxide semi-conductor 0.13um process . A compact size of direct down-conversion and direct up conversion circuits will be presented in this thesis .

近年来随著无线通讯产业的蓬勃发展，微波频带已经趋近於饱和，为了追求更宽的频谱来达到更快传输速率及高资料容量的传输，宽频的毫米波频段提供了解决此问题的途径，毫米波无线通讯系统提供了相对於微波通讯系统宽频的优点，且为了更有效的使用频谱，各种不同且复杂的数位调变方式及方法被发表出来，越复杂的调变方式其所需的线性度越高，且需要更多不同的相位讯号来完成调变的过程，因此高线性度及四相位的调变及解调器将是此篇论文的研究重点，为了达到高整合性，高效能，及低成本的电路设计，我门利用互补式金氧半导体制程来完成此电路设计，因此一小面积的直接降频(Direct down-conversion)及直接升频(direct up-conversion)电路将在文中介绍。

Wavelet modulus maxima with high frequency and low frequency coefficients were obtained firstly through multiscale decomposition of well logging data;then important wavelet coefficients were chosen according to the fusion principle where high frequency coefficients were taken as maximal absolute values and low frequency coefficients were selected by edge detection principle;finally alternating projection algorithm was applied to reconstruct the fusion curve.

首先对原始测井曲线进行多尺度分解，得到不同尺度下的小波低频系数和高频模极大值；然后选用高频系数取绝对值极大、低频系数采用边缘法的融合规则，选取重要的小波系数；最后利用交替投影算法重构融合曲线。

The excellent agreements between simulated and measured results prove the accuracy of the established circuit model. Moreover, the varactor was added to the resonator to adjust its resonant frequency. As expected, the reactance introduced by the varactor indeed affects the net inductance and capacitance obviously. It is noted that, not only the shift with the center frequency, the inductive or capacitive of the reactance can also provide a parameter to switch its frequency toward the two directions away from the one without varactor. As a consequence, a wideband tunable band-pass filter is achieved. Although the bad quality factor with the diode strongly increases the insertion loss, this concept was proved to be available for effectively tuning the center frequency of such a class of band-pass filter.

另外，在共振器上的varactor是用来调整共振器的共振频率，如预期的，由varactor所造成的电抗确实的影响到共振器的总电感和电容值，值得一提的是，不仅滤波器的中心频率可以被改变，这电抗是电感性或是电容性也将决定滤波器的中心频率将大於或小於未加varactor时滤波器的中心频率，利用这个结果，我们也实现了一个宽的可调频率带通滤波器，虽然不理想之二极体的Q值增加了滤波器的介入损失，但这原理是被证明可有效的用於调变带通滤波器的中心频率。

Experiments shows that it can detect the carrier frequency and the low frequency of modulation signal as expected, the resolution of the carrier frequency is 0.3Hz,the detecting error is within ±0.5Hz, and the resolution of the low modulation frequency is 0.07Hz, the detecting error is within ±0.05Hz.

实验结果表明该检测仪能很好地检测出信号的载频和信号的低频调制信息，其中信号载频的分辨率为0.3Hz，误差范围在±0.5Hz 以内，低频信息的分辨率可达0.07Hz，信号的误差在±0.05Hz。

If you were not , and OS X just booted normally, have no fear.

如果你没有，和OS X刚刚启动通常，没有恐惧。

I only want to preserve our all .

我只想保存好我们的一切