具备参考级频率准确性的紧凑结构超再生接收机  

A Compact Super-Regenerative Receiver with Reference-Class Accuracy of Frequency

作　　者：郑卫国[1] 蔡敏[1] 贺小勇[1] ZHENG Weiguo;CAI Min;HE Xiaoyong(School of Electronic and Information Engineering, South China University of Technology, Guangzhou 510640, Guangdong, China)

机构地区：[1]华南理工大学电子与信息学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2018年第3期65-71,共7页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家科技重大专项(2010ZX03001-004-03)~~

摘　　要：针对传统超再生接收机频率准确性不高的问题,提出了一种应用于低速率、短距离无线传感器网络的基于晶体的超再生接收机.该接收机使用晶体振荡器取代传统的由电感电容或者电阻电容构成的超再生振荡器;借助晶体超高的品质因数,该超再生接收机实现了与晶体振荡器一样的接收频率准确度和稳定性,并且不受工艺、工作电压和环境温度的影响.文中使用0.18μm CMOS工艺实现了一个原型芯片,该芯片运用双向驱动电路,克服了晶体起振慢和不易完全停振的挑战,实现了参考时钟振荡器按照超再生方式运行和-78 dBm的灵敏度(1 kb/s数据率).测试数据表明,该接收机的频率选择性改善达50倍,灵敏度中心频率偏离目标频率仅7×10^(-6),达到了参考级频率准确性的精度.该接收机外围电路只需一个晶体和少量电源滤波电容,为无线传感器网络等应用提供了一个非常紧凑的方案,特别适用于无线内窥镜胶囊应用.To overcome the poor frequency accuracy and selectivity of the conventional super-regenerative receiver（SRR）,a SRR based on crystal has been proposed for low-data rate and low distance wireless sensor network（WSN）. This SRR adopts a crystal oscillator（XO） as a super-regenerative oscillator（SRO） instead of the conventional LC or RC oscillator. With the help of the ultra-high quality factor of the crystal this SRR has achieved the same accuracy and stability of working frequency as a crystal,and is immune to variations of process,voltage and temperature. A prototype chip,implemented in 0. 18-μm CMOS technology,utilizes a bi-direction driver to overcome the challenges of slow start-up and fully quenching,makes a reference XO work in a super-pre-generative manner,and then achieves sensitivity of -78 dBm（1 kb/s data rate）. The measured data show 50 times improvement on the frequency selectivity,and 7 × 10^-6 frequency error from the target frequency,which matches the reference-class accuracy. This receiver supplies a very compact solution with only a crystal being needed outside except several decoupling capacitors,which is suitable for WSN applications,e. g. wireless capsule endoscopy.

关 键 词：超再生接收机 频率选择性 晶体振荡器 紧凑接收机 无线传感网 

分 类 号：TN47[电子电信—微电子学与固体电子学]