Electric field fit and error calculation of the calibration system of BPMs for HLS injection system

The author describes the calibration of the newly manufactured BPMs developed for injection system upgrade in NSRL phase II project, as well as the electrical field fitting and error calculation. The antenna calibration system employs an equipment whose precision adjusted to 10 μm and with vertical vacuum pipelines, and a signal processor with 1 μm of resolution and working in RF of NSRL ring. The fitting error of the electric field is presented. With the calibrating system and processing method which has a system error about +- 15 μm and the precision of 1 μm, the authors have completed the calibration and quality checking of the developed equipment. Due to the vertically fixed beam pipe and the antenna's movement to simulate beam orbit deviation, as well as the adoption of the RF CW to simulate the beam instead of the traditional 5 MHz CW source, the results show fine precision and better reliability