电子学报
電子學報
전자학보
ACTA ELECTRONICA SINICA
2014年
12期
2495-2500
,共6页
RFID阅读器%零中频%载波泄漏%载波抵消技术%直流偏移%直流反馈环路
RFID閱讀器%零中頻%載波洩漏%載波牴消技術%直流偏移%直流反饋環路
RFID열독기%령중빈%재파설루%재파저소기술%직류편이%직류반궤배로
RFID reader%zero IF%carrier leakage%carrier cancellation technology%DC offset%DC feedback loop
基于无源电子标签的RFID读写器系统通常采用所谓“零中频”接收方案,采用该方案会造成射频信号发射端和接收端之间的载波泄漏,其结果是一方面接收机前端容易饱和因而减少了系统通信距离;另一方面会带来所谓的“直流偏移”问题从而增加了系统误码率.本文提出了两个措施来解决或改善这一问题.首先,将载波抵消技术应用到2.45 GHz频段的RFID读写器中,采用微带电路进行载波泄漏抵消电路的设计,通过ADS软件仿真、制作并测试样机,文中给出了改进后环行器泄漏功率的抵消结果.其次,提出一种带有直流反馈环路的宽带高增益直流放大器,用于放大基带信号并自动补偿混频器带来的直流分量,输出波形无明显失真,从而降低了读写器读取电子标签数据的误码率.
基于無源電子標籤的RFID讀寫器繫統通常採用所謂“零中頻”接收方案,採用該方案會造成射頻信號髮射耑和接收耑之間的載波洩漏,其結果是一方麵接收機前耑容易飽和因而減少瞭繫統通信距離;另一方麵會帶來所謂的“直流偏移”問題從而增加瞭繫統誤碼率.本文提齣瞭兩箇措施來解決或改善這一問題.首先,將載波牴消技術應用到2.45 GHz頻段的RFID讀寫器中,採用微帶電路進行載波洩漏牴消電路的設計,通過ADS軟件倣真、製作併測試樣機,文中給齣瞭改進後環行器洩漏功率的牴消結果.其次,提齣一種帶有直流反饋環路的寬帶高增益直流放大器,用于放大基帶信號併自動補償混頻器帶來的直流分量,輸齣波形無明顯失真,從而降低瞭讀寫器讀取電子標籤數據的誤碼率.
기우무원전자표첨적RFID독사기계통통상채용소위“령중빈”접수방안,채용해방안회조성사빈신호발사단화접수단지간적재파설루,기결과시일방면접수궤전단용역포화인이감소료계통통신거리;령일방면회대래소위적“직류편이”문제종이증가료계통오마솔.본문제출료량개조시래해결혹개선저일문제.수선,장재파저소기술응용도2.45 GHz빈단적RFID독사기중,채용미대전로진행재파설루저소전로적설계,통과ADS연건방진、제작병측시양궤,문중급출료개진후배행기설루공솔적저소결과.기차,제출일충대유직류반궤배로적관대고증익직류방대기,용우방대기대신호병자동보상혼빈기대래적직류분량,수출파형무명현실진,종이강저료독사기독취전자표첨수거적오마솔.
RFID reader system which is based on passive RFID tags typically takes the“zero-IF”receiving solution.This so-lution will cause carrier leakage between the sender and receiver of RF signal .This carrier leakage will cause two undesirable re-sults:one is that it’s easier for the front of receiver to become saturated which will reduce the communication distance of system;the other is that the“DC offset”phenomenon will be caused then the bit error rate of system will be increased .Therefore,two measures are proposed in this paper to solve this problem .Firstly,the carry cancellation technology is be applied in the RFID reader at 2.45GHz band,and the microstrip circuit is used in the design.By simulation and prototyping test,the results of leakage power of improved circulator are given .Secondly,a wideband and high-gain DC amplifier with DC feedback loop is proposed,it is used as the baseband signal amplifier without distortion and it can compensate the DC component brought by the mixer automatically .Thus, it will reduce the bit error rate of RFID readers when the electronic tags are readed .