RDS技术原理与接收机电路设计

介绍了一种在普通FM广播信号中增添数字信号的技术——RDS(Radio Data System)技术。首先详细描述了RDS的技术原理与标准,在此基础上又给出了可靠的收发电路设计方案。     

高速模数转换器AD9283在中频数字接收机中的应用

AD9283是AD公司生产的8 bit高速A/D,输入带宽达475 MHz,最高抽样速率为100 MS/s.高性能、低功耗等使其应用于小信号模数转换.为了将其应用于S波段遥测中频数字接收机中,研究了AD9283工作原理和典型应用.介绍了AD9283的主要特点及典型应用电路,给出了其应用,其中A/D采样基于带通采样定理,这样就降低了后级信号处理难度,介绍了基于史密斯圆图法的A/D输入阻抗匹配电路设计,并给出了几个中频频点的匹配参数,最后指出了AD9283在实际应用过程中应注意问题.     

5Gb/s单片集成GaAs MSM/PHEMT 850nm光接收机前端

采用0.5μm GaAs PHEMT工艺研制出了一种单片集成850nm光接收机前端,它包括金属-半导体-金属(MSM)光探测器和分布放大器.探测器光敏面积为50μm×50μm,电容为0.17pF,4V偏压下的暗电流小于17nA.分布放大器-3dB带宽接近20GHz,跨阻增益约46dBΩ;在50MHz～16GHz范围内,输入、输出电压驻波比均小于2;噪声系数在3.03～6.5 dB之间.光接收机前端在输入2.5和5Gb/s非归零伪随机二进制序列调制的光信号下,得到较为清晰的输出眼图.     

高灵敏度CMOS光电集成接收机设计

设计了一个由调节型级联跨阻抗放大器(TIA)和双光电二极管(DPD)构成的CMOS光电集成(OEIC)接收机.具体分析了这个光电集成接收机的噪声和灵敏度及其相互关系.接收机中的噪声主要是电路中电阻的热噪声和MOS器件的闪烁噪声.提出了优化接收机灵敏度的方法.通过低成本的CSMC 0.6μm CMOS工艺流片并对芯片进行了测试.从测试眼图可知,该CMOS光电集成接收机可工作在1.25GB/s的传输速率下,灵敏度为-12dBm.     

200 MHz带宽压缩接收技术研究

从傅氏变换基本公式出发,介绍了以色散延迟线（SAW DDL）器件通过“相乘-卷积-相乘（M-C-M）”方式实现傅氏变换的方法。以线性调频（chirp）傅氏变换为基础,研制了测频带宽大于200 MHz、频率分辨小于5 MHz、适应100 ns脉冲的接收机用测频模块,同时给出了样品实验结果和测试波形图,并进一步探讨了改进性能的途径。     

高速超宽带脉冲检测电路的设计

在介绍了一种基于TH-PPM调制方式的并行检测接收机方案的基础上,结合UWB脉冲信号的时域特征提出并实现了一种结构简单、性能稳定的脉冲能量检测电路.实验结果表明该电路可在100Mb/s的高传输速率情况下取得较好的超宽带信号检测效果.     

低功耗CMOS限幅放大器设计

利用0.18μm CMOS工艺设计了应用于光接收机中的10Gb/s限幅放大器.此限幅放大器由输入缓冲,4级放大单元,一级用于驱动50Ω传输线的输出缓冲和失调电压补偿回路构成.输入动态范围为38dB(10mV～800mV),负载上的输出限幅在400mV,在3.3V电源电压下,功耗仅为99mW.整个芯片面积为0.8×1.3mm2.     

A regression approach to ROC surface, with applications to Alzheimer’s disease

We consider the estimation of three-dimensional ROC surfaces for continuous tests given covariates.Three way ROC analysis is important in our motivating example where patients with Alzheimer’s disease are usually classified into three categories and should receive different category-specific medical treatment.There has been no discussion on how covariates affect the three way ROC analysis.We propose a regression framework induced from the relationship between test results and covariates.We consider several practical cases and the corresponding inference procedures.Simulations are conducted to validate our methodology.The application on the motivating example illustrates clearly the age and sex effects on the accuracy for Mini-Mental State Examination of Alzheimer’s disease.     

Equivalent Model, Error Analysis, and Design Steps of AGC Loop for MM-Wave Receiver

Automatic Gain Controlled (AGC) Loops are used in MM-Wave receiver in wide-ranging. In this paper, the equivalent model and loop equation of AGC Loop are built, the loop errors are analyzed and then the design steps of AGC Loop are given out.     

A Digital TV Content Protection System

To meet the demand of the digital right management for digital TV content, a unified digital content protection framework for various digital interfaces in digital TV, named Digital TV content protection system （DCPS） is proposed, which comprises two parts： the broadcast head-end content protection DCPS-Flag and the digital TV receiver content protection DCPS-CP. The DCPS system aims at achieving three aspects. First, it is to achieve secret transmission of audiovisual content between the interfaces in valid devices. Second, it is to achieve the integrality between the related control information in the valid devices. Third, it is to maintain the integrality of the system by the way of revoking the invalid devices. Analysis shows the security of DCPS system is based on the secrecy of key, which is unrelated to the algorithm itself. And the practical application also shows the good performance of DCPS with low computation and high real time capability, and it can replace the high cost HDCP.