频率失真

受限于DDS芯片的调频转换速率，在大带宽下，DDS产生的线性调频信号相比理论信号可能存在频率失真。

Compared to the theory signal , the chirp produced by DDS under large bandwidth , may have frequency distortion due to the limited chirp-rate .

文中提出了理想频率失真系数M0的表达式和目标函数y的表达式。

The expressions of ideal frequency distortion M_0 、 objective function Y are presented .

介绍了一种中高频暂态电流传感器，这种电流传感器采用非晶态合金作为导磁材料，能测量20kHz的暂态电流，线性度达0.6%，无频率失真。

This paper introduces a middle and high frequency current sensor . The sensor uses Fe-based super microcrystalline soft magnetic alloy as core and can measure 20 kHz transient current , Its linearity reaches up to 0 6 % , without frequency distortion .

研究了双线性变换中的频率失真。

The frequency infidelity of Bi Linear Transform is investigated in this paper .

信号的失真分为频率失真、相位失真和波形失真等三种。

Signal distortion includes three kinds of distortion : frequency , phase and waveform .

双线性变换中的频率失真

Frequency Infidelity of Bi - Linear Transform

取样法测量中频率失真的补偿

Frequency Distortion Compensation in Sampling Measurement

研究结果表明，双线性变换中的频率失真与采样频率和系统本身的特性有关，当系统特性确定后，增加采样频率，可以减少误差。

The results obtained in the paper show that the frequency infidelity in Bi Linear Transform is related to sampling frequency and the characteristics of the system . The higher the sampling frequency is , the less the error there will be in a certain system .

取样脉冲竟度带来的频率非线性失真，可以采用数字信号处理加以补偿。

The frequency nonlinear distortion caused by sampling pulse duration can be compensated by making use special designed FIR digital filter .

无线信号在无线信道中传播，容易受到多径时延扩展、多普勒频移、角度扩展等多径衰落特性影响，导致接收信号在幅度、相位和频率上失真。

Wireless signal propagated in the wireless channel will be affected by multi-path time delay spread , Doppler shift , angular spread and other characteristics of multi-path fading , leading to the received signal distortion in amplitude , phase and frequency .

无线信道比有线信道有着更大的随机特性，从而导致接收信号幅度的衰减，相位和频率的失真，对接收机的性能提出了很大的挑战。

What is different from cable channels is that wireless channel has a lot of randomness , and it results in the attenuation of received signal amplitude , phase distortion and frequency distortion , so this is a great challenge in the performance of the receiver .

文献报道的SAW倾斜形换能器的设计方法，不能根除变迹损失，可能引起所需频率响应的失真。

The reported design method of SAW inclined apodized transducers is not free of weigh-ting loss and may distort the desired frequency response .

频率和波形失真度变化在相位表检定中的影响

Influence of frequency and wave distortion on the verification of phasemeter

对声频复制来说，所以重要的事情都可以用四个参数来标出：噪音，频率响应，失真，时基误差。

Only four parameters are needed to define everything that matters for audio reproduction : Noise , frequency response , distortion , and time-based errors .

低频正弦电流源广泛应用于接地网故障诊断、通信、雷达等领域。测试用激励源具有精度高、频率稳定、失真度小的特点。

A low-frequency sine wave current source is widely used in fields of grounding grid fault diagnosis , communication , radar , etc. The source has many characteristics of higher output precision , stable frequency and low total harmonic distortion ( THD ) .

声校准器是一种重要的声学计量器具。依据国家计量检定规程《JJG176&95》，声校准器需要对声压级、频率和谐波失真度3个指标进行检定。

Sound etalon is an acoustic measurement equipment of great significance according to the National Measurement Calibration Standards & JJG176-95 , a sound etalon is required to conduct calibration in three indexes , i.e. , SPL ( sound pressure level ), frequency and harmonic distortion .

发现了建立过程的平滑作用可以明显地削弱信号的谐波分量，并存在一个最佳转换频率，使谐波失真达到最小值。

It shows signal harmonics is obviously weakened by the smoothing action in the setting process and there is a best conversion frequency to minimize harmonic distortion .

这种算法是采用了均值量化的方法，把数字水印嵌入图像的离散小波域，可以检测在空间域和频率域的图像失真。

The watermark was embedded in the wavelet domain using the mean quantization method . This method can be used to detect the distortion both in spatial and frequency domain .

论文描述了测试仪硬件结构和软件程序，给出了信噪比、频率响应以及谐波失真等音频指标的测量算法。

The design process of both hardware and software of the analyzer as well as methods of measuring signal to noise ratio , frequency response and harmonic distortion is described in detail .

然而在有些情形中，由于信道条件极其恶劣，伴随着多普勒频移以及其他类型的频率偏移等非线性失真，导致接收机在同步性能上表现很差。

In some cases , however , like extremely bad channel conditions , along with the Doppler frequency shift as well as other types of frequency offset and nonlinear distortion , system is likely to result in poor performance of the receiver .

针对传统弛张振荡器线性控制能力和频率抖动间的矛盾，对二者合理折中，通过对幅值控制电路电平检测速度的调整，在实现较高控制线性度的同时，抑制了频率失真。

Reasonable trade-offs are made for conflict between control linearity and timing jitter of the conventional relaxation oscillator . By adjusting the level detection speed of amplitude control circuits , excellent control linearity and restrained frequency distortion are realized .