A 0.8-3 GHz RF-VGA with 35 dB dynamic range in 0.13μm CMOS

正A wideband variable gain amplifier(VGA) implemented in 0.13μm CMOS technology is presented. To optimize noise performance,an active feedback amplifier with 15 dB fixed gain is put in the front,followed by modified Cherry-Hooper amplifiers in cascade providing variable gain,which adopt dual loop feedback for bandwidth extension.Negative capacitive neutralization and capacitive source degeneration are employed for Miller effect compensation and DC offset cancellation,respectively.Measurement results show that the proposed VGA achieves a 35 dB gain tuning range with an upper 3-dB bandwidth larger than 3 GHz and the input 1 dB compression point of-29 dBm at the lowest gain state,while the minimum noise figure is 9 dB at the highest gain state. The core VGA(without test buffer) consumes 32 mW from 1.2 V power supply and occupies 0.48 mm2 area.     

一种用于数码视频相机的实时自动聚焦算法

本文针对数码视频相机的噪声大,主体位置不确定性及实时性要求高等特点,详细讨论了传统自动对焦算法的缺陷并提出了一种新的自动对焦算法.该算法采用一种新的可有效抑制高频噪声的对焦量函数--高斯一阶导数(FDOG)来正确评价图像对焦趋势;支持最近主体优先的感兴趣区域自动选择,使得系统可以自动找到主体所在位置进行对焦;结合爬山法,二叉搜索和插值拟合进行对焦搜索,相比传统的两段爬山法,搜索效率提高了40%;通过对聚焦后的图像进行监视,支持视频模式下的动态自动对焦.该算法在一个数码视频相机平台上实现,实验结果验证了算法的优点,适用于高性能数码视频相机.     

人工智能高压电缆隧道建设研究

从"感知层-网络层-平台层-应用层"的设计架构出发,对照智慧电缆线路建设标准,对已有的视频、测温和环境监测系统进行升级改造,并实现应急通讯、消防控制、机器人巡检等34项新功能,全面实现了通道环境深度感知、电缆状态多维感知与诊断、隧道智能消防控制、隧道人员管理与应急指挥等多项应用场景中的设备联动功能,提升了电缆隧道的智能...     

基于干电极的、低功耗的便携式心电传感器接口

This paper describes a low-power portable sensor interface dedicated to sensing and processing electrocardiogram (ECG) signals.Dry electrodes were employed in this ECG sensor,which eliminates the need of conductive gel and avoids complicated and mandatory skin preparation before electrode attachment.This ECG sensor system consists of two ICs,an analog front-end(AFE) and a successive approximation register analog-todigital converter(SAR ADC) containing a relaxation oscillator.This proposed design was fabricated in a 0.18μm 1P6M standard CMOS process.The AFE for extracting the biopotential signals is essential in this ECG sensor. In measurements,the AFE obtains a mid-band gain of 45 dB,a bandwidth from 0.6 to 160 Hz,and a total input referred noise of 2.8μV rms while consuming 1μW from the 1.8 V supply.The noise efficiency factor(NEF) of our design is 3.4.After conditioning,the amplified ECG signal is digitized by a 12-bit SAR ADC with 61.8 dB SNDR and 220 fJ/conversion-step.Finally,a complete ECG sensor interface with three dry copper electrodes is demonstrated in real-word setting,showing successful recordings of a capture ECG waveform.     

A low power 12-bit 30 MSPS CMOS pipeline ADC with on-chip voltage reference buffer

A 12-bit 30 MSPS pipeline analog-to-digital converter(ADC) implemented in 0.13-μm 1P8M CMOS technology is presented.Low power design with the front-end sample-and-hold amplifier removed is proposed.Except for the first stage,two-stage cascode-compensated operational amplifiers with dual inputs are shared between successive stages to further reduce power consumption.The ADC presents 65.3 dB SNR,75.8 dB SFDR and 64.6 dB SNDR at 5 MHz analog input with 30.7 MHz sampling rate.The chip dissipates 33.6 mW from 1.2 V power supply.FOM is 0.79 pJ/conv step.     

一种具有温度补偿的宽带CMOS可变增益放大器

设计实现了一个具有温度补偿的宽带CMOS可变增益放大器,该可变增益放大器的核心电路由三级基于改进型Cherry-Hooper结构的可变增益单元级联而成,并通过一种温度系数增强的且可编程的偏置电路和增益控制电路对可变增益放大器的增益进行温度补偿。采用中芯国际0.13μm CMOS工艺流片,测试结果表明可变增益放大器的可变增益范围为-13～27dB,经过温度补偿后,在相同增益控制电压下其增益在0～75°C温度范围内的变化范围不超过3dB。可变增益放大器的3dB带宽为0.8～3GHz,输入1dB压缩点为-50～-21dBm,在1.2V电压下,功耗为21.6mW。     

一种用于蓝牙系统的延迟锁相正交信号发生器

提出了一种延迟锁相结构的正交信号发生器 ,用于蓝牙的射频信号收发电路。介绍的延迟锁相环路结构使电路性能具有良好的工艺变化不相关性 ,在很宽的频带范围内均可获得高性能的正交信号。电路采用单层多晶硅、四层金属、0 .3 5 μm CMOS数字工艺实现 ,仿真结果表明 :电路稳定工作在 2 .45 GHz频率下 ,在 1 40 MHz的输入信号频率变化范围内 ,输出的正交信号相位偏差低于 1°,幅度偏差小于 5 %。电路主要由有源器件构成 ,面积小     

1.9 GHz高线性度上混频器设计

介绍了采用0.35μm CMOS工艺实现的单边带上变频混频电路。该混频电路可用于低中频直接混频的PCS1900(1 850~1 910 MHz)发射器系统中。电路采用了multi-tanh线性化技术,可以得到较高的线性度。在单电源+3.3 V下,上混频器电流约为6 mA。从上混频电路输出级测得IIP3约8 dBm,IP1dB压缩点约为0 dBm。