本文介绍了基于MicroTCA.4标准的新型宽带射频前端的设计。该射频前端可以实现300MHz^6 GHz频率范围内的下变频及50 MHz^6 GHz范围内的矢量调制上变频。同时射频前端具有可调衰减、温度监测、功率检波、IQ校准、板卡管理等功能。通过测试,板卡下变频端口间隔离度大于70d B,下变频线性区间大于35 d B,幅度误差小于0.03%,相位误差小于±0.03°;上变频载波泄露小于-45 d Bm,边带抑制大于50 d B。
The RF system for the Beijing Electron Positron Collider Upgrade(BEPCⅡ)Project had been working since Nov,2006.It consists of 3 subsystems including the superconducting cavity,the klystron and the low level RF system.Compared with the former RF system,the operating frequency has been changed from 200MHz to 499.8MHz, and the superconducting cavity has been used to replace the normal cavity.Up to now,the RF system performance is good and achieves the designed target.
