BPM signal conditioning for a wide range of single-bunch current operation in the Duke storage ring

The beam position monitor system of the Duke storage ring has been in operation since 1998. Recently, by injecting at higher energy with a booster synchrotron, the single bunch current threshold is much more increased. The high peak voltage associated with high single-bunch current degrades the performance of the BPM system and can potentially damage the BPM electronics. To improve the accuracy of the orbit measurement, we carefully studied the BPM signal and found a way to overcome this problem. This paper reports our findings and presents a solution to condition the signal for a wide single-bunch current operation.