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一种基于零阶谐振特性的新型微带阵列天线 总被引:1,自引:1,他引:0
设计了一种中心频率在2.45GHz的新型零阶谐振微带阵列天线。该天线由4个谐振单元级联组成,可形成有耗的零阶谐振结构。其测量结果表明:在中心频率为2.45GHz时,其电压反射系数达到了-32dB,对应的带宽为1.5%,增益达到10.8dBi,相对于单个贴片天线增加了5.6dB,与仿真结果吻合较好。与一般的微带阵列天线相比,其尺寸减小,性能提高,在微波能量传输和目标探测等领域具有良好的应用前景。 相似文献
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锁相频率合成(PLL)和直接数字频率合成(DDS)相结合的技术广泛应用于信号源的设计。文章采用DDS激励PLL的技术,设计了C波段(5GHz6GHz)线性调频信号源的实现方案,并对信号源的频率建立时间和相位噪声进行了仿真,最后重点研究了基于DDS芯片AD9852的锁相环激励信号源的设计。 相似文献
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本文以磁感应成像系统中激励源的设计为例,介绍了利用DSP Builder进行硬件设计的设计思路及方法.文中根据磁感应成像激励源的参数要求,提出了基于直接数字频率合成的多频移相激励源的总体设计方案;说明了利用DSP Builder搭建激励源模型的方法及步骤,最后通过模型仿真,验证了设计激励源模型的可行性. 相似文献
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设计了一种Ku波段双频正交极化256元微带阵列天线。该阵列天线的正交极化辐射通过共面微带线和背向探针分别进行激励,并结合阵列馈电网络的有效设计实现了宽频带、高隔离和高增益性能。仿真和实测结果表明,该阵列天线的垂直极化端口相对阻抗带宽(S11≤-10 dB)达到21.04%,覆盖频率范围10.7~13.33 GHz;水平极化端口相对阻抗带宽达到27.86%,覆盖频率范围12.4~16.37 GHz;两极化端口隔离度高于40 dB;工作带宽内天线增益达到28~30.1 dBi。 相似文献
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设计了一种结构紧凑通用性强的宽频带、高增益、双极化天线单元与阵列,采用开放式可扩展模块化的设计方 法,提出以16单元为子阵可扩展的64单元双极化阵列天线。仿真及实测结果表明,天线相对带宽为39%(VSWR<1.5),频段范围为 3.5GHz~5.2GHz,单元方向图旋转对称,中心频率增益为8.8dB,64单元天线阵列的中心频率增益可高达 26.8dB,该仿真和设计结果可为射电天文阵列馈源以及第5代移动通信系统基站天线设计提供参考。 相似文献
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阵列接收机是将其前端阵列天线放置于射电望远镜焦平面处,结合后级波束合成网络以形成多个连续波束,用以同时观测一片连续天区、实现更大视场覆盖的接收机技术。本文理论设计了工作在1.25 GHz的十六阵元矩形排布贴片天线阵列,并在该贴片天线阵列样机的基础上进行了实验室测试。在等幅激励、30°设计扫描角度配相下,实测的阵列主波束增益为14.03dBi、扫描角度约为35°。测量结果显示该贴片天线阵列满足设计指标,相关工作对阵列天线的模拟波束合成及扫描性能验证也具备较好的指导意义。 相似文献
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以典型规则干扰波形和非规则干扰波形为例构建了不同的干扰源模型,研究和分析了在不同干扰源模型下连续波多普勒引信的起爆高度,利用MATLAB-Simulink搭建仿真系统,对输出的仿真结果进行探讨和分析. 相似文献
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文中介绍了软硬件协同验证的原理及流程,把软件作为硬件激励进行验证可以在实际的工作环境中来模拟设计,更为充分有效地验证硬件,也避免了编写测试代码验证设计中的典型应用.但是使用软件驱动的验证,还需要解决软件的调试问题.文中利用可执行文件中的调试信息,将软件源文件和硬件仿真产生的波形文件连接起来,进行软硬件协同仿真,并且通过对仿真波形中信号分析进行软件调试. 相似文献
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涡流检测技术采用频谱丰富的正弦信号作为激励源,响应中包含多个频率成分,增强了涡流检测的抗干扰能力.将涡流检测技术、数据采集技术与虚拟仪器技术有机结合起来,开发了适用于在线检测的涡流检测系统.系统由脉冲涡流检测硬件电路、PXI总线系统以及相关软件组成.硬件电路可产生性能良好,频率、幅值稳定的激励信号,频率范围为0~5 M... 相似文献
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本文介绍了一项以TMS320C54X系列DSP芯片作为核心处理单元的波形发生器的课程设计。本系统采用单片机和DSP分别作为上位机和下位机,上位机接收键盘输入的波形参数,下位机接收上位机输入参数并以此生成相应波形,最后通过数模转换芯片输出模拟信号。整个系统充分结合了课程的理论与实践环节,达到了很好的教学目的。 相似文献
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JongKuk Kim HernSoo Hahn Uei-Joong Yoon MyungJin Bae 《Wireless Personal Communications》2009,50(4):435-446
Speech synthesis can be classified into waveform coding, source coding, or hybrid coding by the synthesis method. Among these,
waveform coding is especially suitable for high-quality speech synthesis. However, synthesis techniques using syllable or
phoneme unit is not desirable since it fails to separate the excitation and the formant part to handle speech. Therefore,
there is a need for a pitch alteration method to apply in synthesis using waveform coding. This study proposes a pitch alteration
method that uses spectrum scaling after flattening the spectra by a sub-band linear approximation to minimize the spectrum
distortion. A comparison with LPC (Linear Predictive Coding), Cepstrum and lifter function is presented to show the better
performance of the proposed method. Estimation method seeks each of the distributions of the flattened signal and measures
the degree of the flattened spectrum Signal, which is normalized, so the highest point amounts to zero, and the distribution
of the signal, whose average is zero, is calculated. The results are presented by the spectrum distortion rate to estimate
the performance of the proposed method. The average spectrum distortion rate kept below the average 2.12%, showing the proposed
method’s superiority in comparison with the other existing approaches.
相似文献
MyungJin BaeEmail: |
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本文介绍一种新型的电视特技设备,其工作原理、设计思想和电路结构与现有的扫换特技设备均不相同。该设备不用传统的“三基波迭加法”,而采用单片微机直接产生扫换波形,因此功能齐全、硬件简单、性能稳定可靠、易于生产,并具有较高的性能价格比。本文对“微机特技”的基本设计思想、电路工作原理和结构、软件设计及关键技术都一一作了介绍。 相似文献
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《Mechatronics》2016
Conventional electro-hydraulic excitation is usually controlled by a servo valve employing a sliding spool type construction. However, the comparatively slow response of the servo valve will greatly limit the system's high-frequency performance. Therefore, a rotary valve with the rotary motion of the spool as a new excitation mechanism is proposed to obtain the desired excitation, especially a high-frequency excitation wave for fatigue. An electro-hydraulic exciter using a combination of a three-way two-dimensional rotary valve (2D rotary valve) and an unequal area piston is taken as an example. Analysis of the vibration output to a typical wave input yields an analytic solution of the vibration waveform excited by this electro-hydraulic system. The mathematical formulation of the harmonics is also derived. Additionally, an electro-hydraulic excitation test-bed is built to acquire an experimental excitation wave. Consequently, the analysis of the excitation waveform in an approximate analytical and experimental method is used to verify access to high-frequency excitation, even resonance excitation. 相似文献
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随着集成电路设计规模的不断扩大,SOC设计的时代已经到来。SystemC作为一种新兴的SOC设计语言,它本质上是在C++的基础上添加的硬件扩展库和仿真核,这使得SystemC可以建模不同抽象级别的包括软件和硬件的复杂电子系统。在C++环境中,它支持软件、硬件和接口描述。利用SystemC的这些特性实现了对UART的建模,并用波形图验证了仿真结果。 相似文献
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介绍了一种应用远程激发技术的大功率集成LED光转换光源,通过使用固晶区无绝缘层的镜面铝基板进行集成封装蓝光LED光源,即COB光源。所制蓝光光源与远程激发荧光粉模块结合制成LED光转换光源。利用镜面铝基板的高导热系数,解决多种LED封装形式下芯片点亮温度过高、光源衰减快的问题。采用LED荧光高分子模块与蓝光芯片分离结合的远程激发技术制成白光光源,解决荧光粉分布不均、热老化、色偏移问题。通过与传统粉胶封装方式制得的大功率集成LED器件比较测试,该种光源具有防眩光、光色均匀度高、长寿命、节能和环保的优点,从而具有更广泛的用途。 相似文献
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The singularity expansion method (SEM) is applied to study the interaction of a transient electromagnetic plane wave with a printed strip antenna. In SEM, the time-domain response of the element is separated into excitation-independent natural resonances and modes, which have considerable physical significance, and closed-form coupling terms which can be rapidly evaluated as the geometric or temporal properties of the source change. The SEM is demonstrated as applied to the transient microstrip problem, and the effect of varying the properties of the printed circuit substrate over a range of values typically found in microstrip antenna applications is studied. The transient response due to a step and Gaussian excitation is studied. It is found that the level of transient signal induced on a printed element increases with increasing substrate permittivity. The shape of the induced voltage or current waveform is highly dependent on the geometric and temporal properties of the source for elements printed on relatively thin substrates, while, for elements printed on thicker substrates, the shape of the induced waveform is much less sensitive to the form of the excitation, and resembles the oscillation of the fundamental resonance of the antenna 相似文献