结构简单的双信道偏振位移键控光通信系统

提出采用两个光相位调制器组成一个电-光偏振调制器实现双信道偏振位移键控(PolSK)光通信系统方案,并进行了仿真验证.分析了系统的工作原理,给出了关键点的信号的琼斯矢量和星座图,并通过系统仿真计算出了偏振接收、解复用后的双信道数据信号的时间波形.该系统在发射机端,采用平行相位调制方式实现了双信道数据的复用,在接收机端,...     

一种27kV／7AIGBT串联刚性调制器的设计与实现

介绍了一种采用IGBT串联技术实现某行波管27kV／7A大功率刚性调制器的设计方法,给出了主电路的拓扑结构,阐述了调制器工作原理,详细分析了实现该调制器的关键技术,并给出了采用该方案实现调制器的试验结果。     

GaAs多芯片多倍频程矢量调制器

众所周知 ,矢量调制器其相位和幅度均连续可调 ,因此在许多先进的电子系统中 (如空间分集的智能天线系统、移动通信码分多址系统基站中实时控制的超线性功率放大器及雷达系统等 )已广泛应用。采用 Ga As MMIC的矢量调制器 ,由于其体积小、重量轻、开关速度快、几乎无功耗、抗辐射、可靠性高和电性能批量一致性好等显著优点而倍受欢迎。南京电子器件研究所采用 Ga As MMIC多倍频程数字和模拟移相器及低相移 DC～ 5 0 GHz Ga As MMIC压控可变衰减器构成多倍频程矢量调制器 ,获得了较好的结果。在这种多倍频程矢量调制器中 ,根据不同…     

强度调制法测量Stokes矢量元素谱原理研究

介绍了一种测量Stokes矢量元素谱的新方法.该方法通过在普通光谱仪的入射光路前端加上由两个延迟器和一个检偏器组成的调制器,只需一次测量即可解调得到目标的完整Stokes矢量元素谱,能有效解决传统偏振光谱信息获取方法存在的缺陷.给出了新方法实现完整Stokes矢量元素谱测量原理的数学推导,并用计算机数值模拟手段证明了该方法的可行性.     

一种宽带矢量调制器的设计及其应用

矢量调制器是一种可以同时控制微波信号幅度和相位的器件。本文介绍了一种基于新型微带定向耦合器的宽带矢量调制器。新的耦合器结构克服了传统微带耦合器耦合度低、方向性差的问题,也不需要Lange耦合器复杂的加工工艺,在平衡放大器、移相器和衰减器等场合具有广泛的应用。其次,研究了用串联电感对衰减器中PIN二极管的寄生参数进行补偿的一种简单方法,以改善衰减器衰减量变化时的相位性能。该方法原理简单,可在一定带宽内替代复杂的平衡结构,并给出相近的性能。最后给出了矢量调制器的测试结果和它在自适应天线阵等实际系统中的应用情况,并讨论了用于提高载波和边带抑制、满足高精度要求的校准方法。     

C波段单片矢量调制器

<正>随着微波单片集成技术的发展。高精度移相器已成为各种微波整机系统的关键技术之一。矢量调制器能在获得连续可变的相移量的同时。又能满足幅度控制、移位精度控制和解决多位数字移相器级联的要求。由于单片集成矢量调制器具有宽带、连续可调、尺寸小和可成批生产的优点,受到人们特别的重视。 矢世调制器的基本原理是利用调节两个相互正交的矢量来改变合成矢量的相位,从而获得连续变化的相移量。由矢量相加运算法则可知。只要使两个相互正交矢量的幅度取适当值,就可在获得连续变化相移量的同时保持输出幅度不变。本文就是基于这一原理,对单片矢量调制器的电路形式、工艺实现方法进行了原理性的研究。 由于双栅FET的第二栅的特殊作用,使它特别适合用于增益控制的宽带放大器。本文采用两个双栅FET可变增益放大器来控制两个相互正交的矢量幅度,而放大器的增益还可用于减少整个电路的插损。在研制初期,为了使电路简化,采用λ/4微带线来得到两个矢量间的90°相位差。矢量的分离和合成用两个Wilkinson同相功分器实现。双栅FET的S参数是从器件     

I-Q矢量调制器在噪声干扰模拟器中的应用分析

介绍了I-Q矢量调制器的工作原理、典型调制电路及控制部件的概念,并叙述了其在噪声干扰模拟器中的具体应用。     

一种高精度数控矢量调制器的设计

为了提高矢量调制器的技术指标,使得其所应用的射频干扰对消实现更好的性能,该文提出了数字控制矢量调制器的技术方案,可以实现稳定的高精度矢调步进控制。测试结果表明,研制的矢调模块可以实现满足系统要求的0.03dB的步进精度。     

一种基于FPGA的可控FIFO的设计实现

介绍了常规FIFO的基本原理，提出了两种基于FPGA的可控FIFO的实现方案，给出了具体的实现方法，并在IQ矢量调制器中得以具体应用。     

一种数字矢量调制器设计与实现

提出描述了数字矢量调制器的设计方法、实现过程及试验结果。该数字矢量调制器采用数字与模拟相结合、混合集成工艺技术实现,其调试简单,控制电压与电压传输系数成线性关系,一致性好。在VHF频段内,衰减量变化30dB时,其相位误差变化小于±1.5°,I路与Q路的正交性小于±2°。     

A multicarrier QAM modulator for WCDMA base-station with on-chip D/A converter

In this paper, design and implementation of a multicarrier quadrature amplitude modulation (QAM) modulator for a wideband code division multiple access (WCDMA) base-station with a 14-bit on-chip D/A converter is described. The modulator is capable of modulating four carriers with four independent in phase (I) and quadrature (Q) data streams. The proposed modulator structure consists of an interpolation chain for data streams and four digital frequency synthesizer/modulators, which are based on a coordinate rotation digital computer (CORDIC) vector rotation algorithm. The interpolation chain consists of a root-raised cosine pulse shaping filter and three half-band filters for image filtering. The modulated carriers are combined to form a multicarrier WCDMA signal. The SINC-attenuation effect of a digital/analog (D/A) converter is canceled by an inverse-SINC predistortion filter. The multicarrier signal is converted to the analog domain with a 14-bit current steering D/A converter, which is integrated on the same silicon chip. The modulator is implemented with a 0.35-mum BiCMOS process with CMOS transistors only     

Microwave photonic vector modulator for high-speed wireless digitalcommunications

The authors present the design, realization, and experimental results of a microwave/photonic circuit suitable for high-speed direct digital modulation of microwave signals. The modulator employs a combination of microwave, photonic, and digital techniques to produce a discrete phase and amplitude (i.e., vector) modulated carrier signal. The proof-of-concept demonstration presented in this paper was performed using a carrier frequency of 1 GHz and supports BPSK, QPSK, and 16-QAM. The authors also discuss ways to modify the modulator to simultaneously achieve data rates on the order of several hundreds of Mbs and wideband frequency hopping     

A Wideband ΔΣ Digital-RF Modulator for High Data Rate Transmitters

A wideband software-defined digital-RF modulator targeting Gb/s data rates is presented. The modulator consists of a 2.625-GS/s digital DeltaSigma modulator, a 5.25-GHz direct digital-RF converter, and a fourth-order auto-tuned passive LC RF bandpass filter. The architecture removes high dynamic range analog circuits from the baseband signal path, replacing them with high-speed digital circuits to take advantage of digital CMOS scaling. The integration of the digital-RF converter with an RF bandpass reconstruction filter eliminates spurious signals and noise associated with direct digital-RF conversion. An efficient passgate adder circuit lowers the power consumption of the high-speed digital processing and a quadrature digital-IF approach is employed to reduce LO feedthrough and image spurs. The digital-RF modulator is software programmable to support variable bandwidths, adaptive modulation schemes, and multi-channel operation within a frequency band. A prototype IC built in 0.13-mum CMOS demonstrates a data rate of 1.2 Gb/s using OFDM modulation in a bandwidth of 200 MHz centered at 5.25 GHz. In-band LO and image spurs are less than -59 dBc without requiring calibration. The modulator consumes 187 mW and occupies a die area of 0.72 mm².     

高速DAC与正交调制器接口电路设计

结合宽带数字TR组件零中频发射波形产生思想,设计了高速DAC与正交调制器的接口电路。给出详尽设计方法及步骤的同时使用TINA—TI软件对设计的接口电路进行了交直流特性及宽带信号幅频特性仿真,验证了其正确性。     

一种通用数字中频正交扩频调制器的实现

提出了一种适应于宽带扩频通信系统的数字中频调制的实现方案,它基于正交调制、DDS、数字上变频和数字内插等技术,采用通用硬件平台,可以生成多种中频调制信号,可广泛用于数字化扩频通信电台、宽带CDMA、软件无线电、遥控遥测等通信系统中。     

Direct radio-frequency digital angle modulator

A radio frequency angle modulator is proposed with a direct digital data interface using 0.18 /spl mu/m CMOS technology. It consumes 42 mW, occupies a chip size of 0.936/spl times/0.935 mm, and shows a measured error vector magnitude of 0.55% at 2.468 GHz with 5.5 Mbit/s data rate.     

基于子带化的宽带数字波束形成延时补偿新方法

采用宽带信号的相控阵雷达可获得高的距离分辨率,但也面临挑战:宽带数字波束合成和自适应抗干扰。典型的宽带自适应数字波束合成架构中,首先,在基带采用分数延时滤波器实现多通道的延时补偿;然后,将宽带信号分解为许多子带,在每个子带内做传统的窄带自适应数字波束合成;最后,合成为宽带波束输出。该信号处理方法,在宽带条件下,通过宽带延时补偿实现了精确的波束指向,取得了较好的抗干扰性能。文中基于子带化方法,提出了一种新的架构,将延时补偿合并到窄带波束合成中,即用窄带的附加相移,代替了原有的多通道延时补偿单元。结果是该架构中不再需要分数延时滤波器,大大降低了计算量节约硬件资源。同时,仍然保证了宽带阵列雷达波束的精确指向。结合相控阵雷达阵列实例,文中分别采用传统架构及所提出的新架构完成宽带波束合成,给出仿真结果以供对比,证明了新架构的有效性。     

Design and analysis of a low-power discrete phase modulator in a 0.13-/spl mu/m logic CMOS process

This letter reports the design and analysis of a low-power discrete constant envelope phase modulator. The modulator discretely changes the phase of a constant envelope carrier according to the input digital data bits. A test chip was fabricated in a 0.13-/spl mu/m logic complementary metal oxide semiconductor process. The modulator consumes 2mA from a 1.2-V supply, has an operating frequency range between 1.5GHz and 3.3GHz, and can support a data rate up to 225Mbps with better than 5.5% error vector magnitude. The modulator can be designed to generate different modulation schemes by digitally controlling the phase and/or amplitude of the carrier, and therefore potentially can be used in software defined radios.