一种用于GPS接收机中的自适应A/D转换器  

Adaptive Analog-to-Digital Converter for GPS Receiver

作　　者：段静波[1] 曹奉祥[1] 李永明[1] 张春[1] Seeteck Tan 

机构地区：[1]清华大学微电子学研究所,北京100084 [2]O2Micro Pte Ltd.,Singapore

出　　处：《微电子学》2007年第3期378-381,共4页Microelectronics

基　　金：国家自然科学基金资助项目(60475018;60236020);北京市科技计划资助项目(D0305003040111)

摘　　要：基于SMIC 0.18μm工艺,设计了一个2位自适应A/D转换器。设计中,采用新的2位结构和充电电流可调电荷泵,使其不但对连续波干扰可起到很好的抑制作用,改善转换器在高斯噪声环境中的转换增益,而且可以抑制不同强度的连续波干扰。仿真结果表明,其输入动态范围为50 dB,采样带宽为20 MHz,可满足GPS应用的要求。该电路已应用在BPSK调制的直接扩频GPS接收机中。A 2-bit adaptive analog-to-digital converter is designed using SMIC＇s 0. 18μm CMOS process. A new 2-bit structure and a current tunable charge pump are used. Thus, it can almost completely suppress the continuous wave and improve its conversion gain in Gaussian noise environment, and suppress interferences with different amplitude. Simulation results show that the converter has achieved an input dynamic range of 50 dB and a sampling bandwidth of 20 MHz, which meets the specification of GPS. The circuit has been used in a BPSK modulated direct GPS receiver.

关 键 词：自适应A/D转换器 GPS接收机 扩频通信 连续波干扰 

分 类 号：TN911.8[电子电信—通信与信息系统]