摘要
针对近年来出现的文字手表、短信橡皮等无线作弊工具不易被侦测的特点,设计了一种基于扫频干扰的考场防作弊干扰器;该干扰器采用DDS生成扫频波形,集成VCO的PLL芯片生成本振信号,正交调制方式完成上变频,具有扫频范围宽,扫频范围及扫频步进可设置且频率控制准确等优点;实验结果表明,该系统能有效屏蔽频率范围为400～470MHz的短信橡皮等文字作弊工具,且不会影响其他正常无线通信业务。
To interfere the word watch,messaging rubber and other wireless cheating tools that appear in recent years,an anti-cheating jammer based on sweep interference was designed.The jammer generate sweep waveform using DDS,get local oscillator signals from PLL chip with Integrated VCO,complete upconversion with quadrature modulator.The sweep range and frequency step can be set and precisely controlled in a wide range.Experiment shows that the sweep jammer can effectively shield cheating tools such as messaging rubber,and will not affect other normal wireless communications business.
出处
《计算机测量与控制》
CSCD
北大核心
2012年第2期520-522,共3页
Computer Measurement &Control
关键词
扫频干扰
短信橡皮
防作弊
sweep interference
messaging rubber
prevent cheating
