PCI-5421 可抑制不需要的高频信号图像

Description

PCI-5421 可抑制不需要的高频信号图像

任意波形发生器是一种特殊的信号源，它具有综合具有其它信号源波形生成能力，因而适合各种仿真实验的需要。它可以仿真各种测试信号，提供给被测电路，以达到测试的需要。
NI 5421系列采用100 MS/s、16位数模转换器(DAC)和简洁的后端模拟设计，具有91 dBc的近距离无杂散动态范围(SFDR)平均噪声密度为-148 dBm/Hz。这些功能使其非常适合通信中常见的最严格的频域应用。根据信号和应用需求，用户可以选择2x、4x或8x插值，以获得高达400 MS/s的有效采样率。对于要求苛刻的时域应用，NI 5421系列在模拟输出处具有<5%的脉冲畸变和<1.0 ps rms抖动。

模拟输出路径具有43 MHz 7极椭圆模拟滤波器，可抑制不需要的高频信号图像。用户还可以选择50或75？输出阻抗并以三位数的精度改变输出衰减。此外，还可以使用直接路径绕过输出增益和衰减。直接路径非常适合中频(IF)应用，其通带平坦度在0至40 MHz范围内为±0.25 dB。

共享波形和指令存储器

由于NI 5421系列基于SMC架构构建，因此它们使用相同的物理内存来存储波形数据和排序指令。传统上，AWG的指令存储器在物理上与波形数据存储器分开，通常只有几kB。传统AWG有限的指令内存严重限制了可排序的最大波形数量以及AWG的整体灵活性。NI 5421系列的8、32或256 MB板载内存将数据和指令存储在一起，从而可以灵活地使用排序指令所需的空间。通过共享存储器，可以将存储器空间用于具有小波形的非常长的序列、具有非常大波形的短序列或两者之间的平衡。

PCI-5421 可抑制不需要的高频信号图像

Arbitrary waveform generator is a special signal source, it has the ability of synthesizing waveform generation of other signal sources, so it is suitable for various simulation experiments. It can simulate various test signals and provide the tested circuit to meet the needs of the test.
The NI 5421 series features a 100 MS/s, 16-bit digital-to-analog converter (DAC) and a concise back-end analog design with a 91 dBc short-range spury-free dynamic range (SFDR) with an average noise density of -148 dBm/Hz. These features make it ideal for the most stringent frequency-domain applications common in communications. Depending on the signal and application requirements, users can choose between 2x, 4x or 8x interpolation for effective sampling rates up to 400 MS/s. For demanding time domain applications, the NI 5421 series features &lt at the analog output; 5% pulse distortion and < 1.0 ps rms jitter.

The analog output path features a 43 MHz 7-pole elliptical analog filter to suppress unwanted high-frequency signal images. Users can also choose between 50 or 75? Output impedance and change output attenuation with three-digit accuracy. In addition, a direct path can be used to bypass output gain and attenuation. The direct path is ideal for intermediate frequency (IF) applications, with a passband flatness of ±0.25 dB in the range of 0 to 40 MHz.

Shared waveform and instruction memory

Because the NI 5421 series is built on the SMC architecture, they use the same physical memory to store waveform data and sorting instructions. Traditionally, the instruction memory of an AWG is physically separate from the waveform data memory, which is usually only a few kilobytes. The limited instruction memory of a traditional AWG severely limits the maximum number of waveforms that can be sorted, as well as the AWG’s overall flexibility. The 8, 32, or 256 MB of onboard memory in the NI 5421 series stores data and instructions together, allowing for flexible use of the space required for ordering instructions. With shared memory, memory space can be used for very long sequences with small waveforms, short sequences with very large waveforms, or a balance between the two.