一种0.18μm CMOS工艺单电感单模块正交卫星导航接收机射频前端设计

本文介绍了一种改进的单模块化卫星导航射频前端模块的设计.该结构将低噪声放大器,混频器以及压控振荡器层叠级联,并实现电流和功能的复用.仅采用了单个片上螺旋电感作为LC振荡回路,另外增加一个二分电路作为正交本振信号的产生源.文章讨论了该模块的增益规划,噪声系数,以及设计的细节.对相位噪声以及功耗进行了改进.通过0.18μm CMOS射频工艺进行流片验证,获得带内平均噪声系数为5.4dB,增益43dB,三阶交调点-39dBm.测得相位噪声在本振1MHz偏移处小于-105dBc/Hz.整体功耗小于19.8mW,工作电压为1.8V.实验结果证明满足卫星导航射频前端应用的需要.     

A 0.18μm CMOS single-inductor single-stage quadrature frontend for GNSS receiver

This paper presents an improved merged architecture for a low-IF GNSS receiver frontend,where the bias current and functions are reused in a stacked quadrature LNA-mixer-VCO.Only a single spiral inductor is implemented for the LC resonator and an extra 1/2 frequency divider is added as the quadrature LO signal generator. The details of the design are presented.The gain plan and noise figure are discussed.The phase noise,quadrature accuracy and power consumption are improved.The test chip is fabricated though a 0.18μm RF CMOS process. The measured noise figure is 5.4 dB on average,with a gain of 43 dB and a IIP3 of-39 dBm.The measured phase noise is better than -105 dBc/Hz at 1 MHz offset.The total power consumption is 19.8 mW with a 1.8 V supply. The experimental results satisfy the requirements for GNSS applications.     

0.18μm CMOS X波段接收机射频前端设计

本文给出了一个采用TSMC 0.18 m CMOS工艺应用于X波段SAR(合成孔径雷达)的单片接收机射频前端的设计。接收机前端由低噪声放大器和混频器组成,低噪声放大器工作在9 GHz~11GHz,混频器将10GHz的射频信号转换到2GHz中频,本振信号由片外提供。在X波段频率下,尽管CMOS 0.18μm工艺特征频率比较低,工作仍然实现了低噪声系数,提高了集成度。测试结果表明,本设计在300MHz的带宽上实现了20dB的转换增益,噪声系数达到2.7Db,输入1dB压缩点达到-19.2dBm,在1.8V的电源电压下前端消耗26.6mA电流,芯片面积为1.3×0.97mm2。     

某热电厂水处理系统扩容项目的研究与设计

通过对某热电厂化学水处理系统增加预处理水量400 t/h、锅炉补给水产量100 t/h扩容需求以及原水水质的分析,结合厂区现有水处理设施和工艺,对系统扩容升级方案进行研究与设计。介绍了本次项目的工艺路线以及主要设备的设计过程,出水水质满足国家标准《火力发电机组及蒸汽动力设备水汽质量》(GB/T 12145—2016)的有关要求。     

基于CEEMDAN和TEO的配电网行波故障定位方法

针对传统配电网行波故障定位方法中行波信号复杂,波头难以准确识别的问题,提出一种基于自适应噪声完备集合经验模态分解方法（CEEMDAN）和改进Teager能量算子（NTEO）的配电网行波故障定位方法。该方法采用CEEMDAN对初始行波信号进行降噪和分解,并通过NTEO增强高频分量的故障特征从而得到瞬时能量图谱,根据瞬时能量峰值精确标定初始行波波头达到时间,实现快速准确的故障定位。Pscad/Matlab仿真结果表明,所提方法能够适应不同故障类型和过渡电阻,准确进行故障测距,测距误差均在2%以内,相较于传统EMD方法具有更高的定位精度和更快的计算速度。     

水泥窑篦冷机余热发电节能改造数值分析

干法水泥生产工艺中,在回转窑篦冷机段取热进行余热发电是一种有效的节能方法。但是如何在保证不影响二次风、三次风等生产正常用风情况下,使篦冷机内熟料余热得到最大限度利用是节能改造时需要解决的难题。对某10 000 t/d篦冷机12 MW余热节能改造项目进行了数值模拟,模拟了节能改造前后篦冷机内部流场和温度场分布,分析了预计取热方式的可行性,为后续余热发电节能改造项目提供理论支撑。     

Design of a 0.18μm CMOS multi-band compatible low power GNSS receiver RF frontend

This paper presents the design and implementation of a fully integrated multi-band RF receiver frontend for GNSS applications on L-band.A single RF signal channel with a low-IF architecture is adopted for multi-band operation on the RF section,which mainly consists of a low noise amplifier(LNA),a down-converter,polyphase filters and summing circuits.An improved cascode source degenerated LNA with a multi-band shared off-chip matching network and band switches is implemented in the first amplifying stage....     

煤矿支护产品的应用与研究

总结了现今煤矿支护产品的应用现状;从理论上,论证并提出了提高预拉力措施,从巷道顶板的稳定性、工作的可行性考虑,提出了优化锚杆的参数和预应力的合理配置、加强锚杆检测技术及施加水平应力等相关建议。     

Design of a dual-channel multi-mode GNSS receiver with a∑△fractional-N synthesizer

A 72 mW highly integrated dual-channel multimode GNSS(global navigation satellite system) receiver with aΣ△fractional-N synthesizer which covers GPS L1 and the Compass B1/B2/B3 band is presented.This chip was fabricated in a TSMC CMOS 0.18μm process and packaged in a 48-pin 3×3 mm~2 land grid array chip scale package.This work achieves NF≤5.3 dB without an external LNA,channel gain = 105 dB for channel one (Compass B2 and B3 band),and channel gain = 110 dB for channel two(GPS L1 and Compass B1 band).Image rejection(IMRR) = 36 dB,phase noise is -115.9 dBc @ 1 MHz and -108.9 dBc @ 1 MHz offset from the carrier for the two channels separately.At the low power consumption,multibands of GNSS are compatible in one chip, which is easy for consumers to use,when two different navigation signals are received simultaneously.     

求解非线性整数规划的局部极小点的几种算法

给出了几个求解整数非线性规划问题局部极小点的算法,并根据具体的算例比较了它们的优劣性。