A review meeting for the Digital Beam Position Monitor (DBPM), part of the High Energy Photon Source (HEPS) project, was held from Aug 14^th to Aug 18^th. The DBPM was tested offline by two experts, Dr. Kiman Ha and Dr. Yuke Tian, both from Brookhaven National Laboratory (BNL), USA. The reviewers praised the hardware design, firmware development, and algorithm studies. The DBPM test results show that the resolution (RMS) is 1.229 µm for turn by turn data, 0.4 µm (3 s) for FA data, and 0.19 µm (10 s) for SA data.

DBPM test results (Image by IHEP)

Because of the high resolution requirements, the hardware, firmware and algorithms for DBPMs are difficult to design. At present, the only commercially available products are the Libera series of BPMs from Instrumentation Technologies. However, these are expensive, the software is proprietary, and they are difficult to use for further development. The HEPS project will use almost 1000 BPM units, so it was decided to develop DBPMs in-house at IHEP.

The DBPM development group was set up in December 2014. Since then, much work has been done and satisfactory results have been achieved in all aspects of development.

DBPM prototype (Image by IHEP)

In the review meeting, three reports related to the development of hardware, firmware and algorithms were presented by the development group members. After much discussion, questions and lab tests, the reviewers gave many constructive suggestions on system design, system testing, hardware upgrades, firmware optimization and project management. With this review successfully passed, development of the DBPMs for the HEPS project is on schedule.

DBPM development members in the lab with the reviewers (Image by IHEP)