一种长周期的宽带任意波形发生器

描述了一种基于直接数字波形合成(DDWS)技术的长周期宽带任意波形发生器(AWG)。采用PC机内存常用的超大容量高速缓存SDRAMMODULES来实现输出信号的长周期,采用内部具有双路数据分时切换结构的D/A实现输出信号的宽带,采用一片CPLD完成整个系统的时序逻辑控制。还给出了一个实际的AWG系统及其输出信号的测试结果。     

新材料太阳能电池效率与寿命提高

日前，厦门大学物理与机电工程学院康俊勇教授课题组研发成功一种新型太阳能电池，即将氧化锌和硒化锌两种宽带隙半导体材料用作太阳能电池，从而大大稳定了太阳能电池的性能并使其寿命延长。实现了宽带隙半导体在太阳能电池中的应用。     

社区网接入方式的探讨

对构建宽带社区的实现方案进行了探讨，指出建设宽带社区必须因地制宜地合理进行选择。     

智能化电梯轿箱绝对位置测试装置的研究

对智能化电梯轿箱绝对位置测试装置（AWG）进行了研究,设计开发了相应的硬件和软件,该AWG能精确测量出电梯轿厢的位置,比用井道磁开关和增量编码器测量井道中电梯轿厢的位置具有显著优势。     

列阵波导光栅的输入—输出脉宽关系

本文通过给出一个非常简单的关于最短脉冲特征的描述，认定带有一个给定的滤波带宽的列阵波导光栅(AWG)信号分离器产生的有限带宽。这种分析方式与一个带有200GHz信道间和一个4000GHz的自由光谱区(FSR)的AWG的计算机模拟相比较，在实验测量条件下通过一个带有100GHz信道空间和200GHz自由光谱区的短脉冲传输是非常一致的。     

基于MEMS的OXC结构设计及其性能分析

为提高光网络交叉连接能力以及节点交换速度,在详细阐述OXC基本结构和工作原理的基础上,以MEMS为空间交换单元,采用阵列波导光栅(AWG)、波长变换器和可调谐滤波器等关键组件,实现了新型OXC结构的设计,并进一步分析各模块的功能及其优缺点。理论分析表明该OXC插入损耗小,交换容量大并支持节点升级,同时具备全光交叉连接和网络智能的优势,是实现全光通信的核心部件。     

阵列波导光栅(AWG)与光纤列阵的自动化对接耦合技术研究

阵列波导光栅(AWG)与光纤列阵的对接耦合是AWG芯片模块化的核心工作。传统的对接耦合方法是利用手动调芯技术进行对接,但是这种技术存在耗时久,精度低等缺点。为此开发了一种采用质心调芯法和遗传算法的自动调芯耦合技术,该技术具有对准精度高、重复性好、效率高等优点。实验结果显示,使用这种自动调芯耦合技术制造出的48通道AWG器件每个通道的最大插入损耗为4.65dB,满足目前最大插入损耗小于5dB的行业标准。     

激光宽带淬火机理及应用研究

介绍了一种转镜式高功率激光表面处理用宽带扫描器，扫描宽度为10～30mm，连续可调，扫描频率为1000Hz。分析了扫描原理，提出了线光斑宽带方案及传热模型，并计算了其温度场。开展了激光宽带淬火试验和初步工业应用研究。结果表明，线状光斑适用于千瓦级激光宽带淬火。     

轻便浅层地震可控震源的研制

轻便浅层地震可控震源是一种用于浅层地震勘探的激震设备，其主要作用是根据野外的实际勘探目标所确定的参数输出严格控制的Chirp信号。在此，系统地阐述了轻便浅层地震可控震源的工作原理、系统构成及技术特点等。并针对野外浅层地震勘探的特点和要求，进一步探讨了基于直接数字合成(DDS)的任意波形发生器(AWG)的设计、扫描信号相位实时控制等问题。     

随机疲劳分析在机载设备疲劳寿命预测中的应用

提出采用宽带随机振动疲劳寿命数值分析方法在产品设计阶段预测其宽带随机振动疲劳寿命来保证设计方案的首次成功率，并以在宽带随机振动环境下工作的某产品的疲劳寿命设计为例，阐述了整个随机振动疲劳数值仿真分析流程，得到了与试验相吻合的仿真结果，证明了在设计阶段预测产品的疲劳寿命并进行优化是可行的。     

基于VXI总线的新型AWG的设计

基于VXI总线的任意波形发生器是随着计算机技术和微电子技术在测试仪器中的应用而形成和发展起来的一类新型测试仪器。任意波形发生器的价值在于它能真正产生任意波形。文中提出了一种新型的任意波形发生器结构，介绍了基于VXI总线C尺寸任意波形发生器设计的全过程，开发了VXI总线寄存器基接口、用DDS技术设计了功能电路、开发了AWG的软面板、应用控制程序和仪器驱动器，所设计的任意波形发生器的特点是：高速、模块化、方便的波形输入以及和VXI资源相结合。该任意波形发生器模块已应用于模块化雷达自动测试设备中，能提供测试系统所需要的任何波形激励信号。     

Characterization of arbitrary waveform generator by low resolution and oversampling signal acquisition

The paper deals with two relevant aspects of output section characterization of an Arbitrary Waveform Generator (AWG). The first concerns the difficulty of acquiring the output signal from Analog to Digital Converter with both higher linearity and resolution than the AWG under test. The proposed solution makes the problem simpler: oversampling with lower resolution. This result is achieved by means of an acquisition procedure to reconstruct the AWG output signal based on the zero crossing time sequence. Since the reconstructed signal is not uniformly sampled, proper algorithms in the time and frequency domain are proposed to evaluate also the dynamic parameters. The second is linked to the first and concerns the difficulty of evaluating the transfer characteristic. Indeed, the correspondence between the input code and the output sample of the AWG is avoided due to the acquisition procedure proposed, and the AWG operating mode. The proposed procedure allows the input code to be correlated with the corresponding sample of the output signal. It operates in iterative modality to achieve the valid statistical occurrences of the codes. Indeed, owing to the oversampling and the memory size of the acquisition hardware system, the number of samples could be lower than the number of expected output levels of the AWG. Numerical tests have allowed validation of the proposed iterative procedure in the case where the transfer characteristic is affected by nonlinearity, missing code and quantization noise. The experimental setup of the proposed procedure has allowed assessment of: (i) the effectiveness of the iterative procedure in evaluating the transfer characteristic; (ii) the lower resolution of the acquisition hardware system with respect to the direct acquisition. On the basis of the error caused by the numerical procedure and the noise introduced by each device of the experimental set up, the lower bound of the final uncertainty is deduced.     

基于SOPC的任意波形发生器设计

介绍一种采用SOPC技术设计的DDS任意波形发生器。该任意波形发生器采用了FPGA＋USB通信芯片的硬件架构。具有即插即用的特性，能实现两路可调相位差的任意波形输出，波形频率分辨率达到0．1Hz。设计中对DDS的结构进行了改进。使其可以在波形切换时实现平滑输出。     

基于FPGA和单片机的信号发生器设计

介绍了一种基于PC机、单片机、FPGA和数字频率合成技术（DDS）的信号源的设计方法;其中基于FPGA的DDS模块电路采用VerilogHDL语言和原理图相结合的方式设计,上位机的信号源面板以及波形编辑生成系统则基于LabVIEW图形化语言设计;基于FPGA的信号发生器,可以在不改变硬件平台的情况下,随时对信号源系统进行重构或升级,使得应用非常灵活和方便;特别是可以通过USB2.0接口和PC机连接,使得任意波的产生更加方便和快捷;实验结果表明整个设计可以产生0.01Hz-10MHz的任意波及正弦波、方波、三角波等常规的函数信号。     

基于LabVIEW的任意波形发生器设计

设计并实现了靶场测试环境中的用于检验光电靶后续设备的任意波形发生器。该系统硬件包括PC机、PXI-1000B机箱、MXI-3外置控制器和PXI-6025E数据采集板卡。该波形发生器在上述硬件的基础上,利用图形化编程软件LabVIEW编制了用户控制软面板。系统主要功能包括:产生各种标准波形,利用鼠标绘制任意波形,波形编辑,任意波形输出等,能满足实际测试的各种需要。     

A broadband Fourier transform microwave spectrometer based on chirped pulse excitation

Designs for a broadband chirped pulse Fourier transform microwave (CP-FTMW) spectrometer are presented. The spectrometer is capable of measuring the 7-18 GHz region of a rotational spectrum in a single data acquisition. One design uses a 4.2 Gsampless arbitrary waveform generator (AWG) to produce a 1 mus duration chirped pulse with a linear frequency sweep of 1.375 GHz. This pulse is sent through a microwave circuit to multiply the bandwidth of the pulse by a factor of 8 and upconvert it to the 7.5-18.5 GHz range. The chirped pulse is amplified by a traveling wave tube amplifier and broadcast inside the spectrometer by using a double ridge standard gain horn antenna. The broadband molecular free induction decay (FID) is received by a second horn antenna, downconverted, and digitized by a 40 Gsampless (12 GHz hardware bandwidth) digital oscilloscope. The second design uses a simplified pulse generation and FID detection scheme, employing current state-of-the-art high-speed digital electronics. In this spectrometer, a chirped pulse with 12 GHz of bandwidth is directly generated by using a 20 Gsampless AWG and upconverted in a single step with an ultrabroadband mixer. The amplified molecular emission is directly detected by using a 50 Gsampless digital oscilloscope with 18 GHz bandwidth. In both designs, fast Fourier transform of the FID produces the frequency domain rotational spectrum in the 7-18 GHz range. The performance of the CP-FTMW spectrometer is compared to a Balle-Flygare-type cavity-FTMW spectrometer. The CP-FTMW spectrometer produces an equal sensitivity spectrum with a factor of 40 reduction in measurement time and a reduction in sample consumption by a factor of 20. The CP-FTMW spectrometer also displays good intensity accuracy for both sample number density and rotational transition moment. Strategies to reduce the CP-FTMW measurement time by another factor of 90 while simultaneously reducing the sample consumption by a factor of 30 are demonstrated.